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Seeing is natural, but viewing is not: teaching visual literacy in a rural classroom

- Mbelani, Madeyandile, Murray, Sarah R

Authors: Mbelani, Madeyandile , Murray, Sarah R
Date: 2009
Language: English
Type: text , Article
Identifier: vital:7022 , http://hdl.handle.net/10962/d1007203
Description: This paper reports on a collaborative action research case study into Grade 10 teaching and learning of visual literacy in a rural high school into the Eastern Cape, South Africa. Visual literacy is a new aspect that has been incorporated in English First Additional Language National Curriculum Statement (Grade 10-12), which has been implemented in Grade 10 from 2006. With the aim of gaining knowledge and improving performance in visual literacy, I designed a unit of lessons, which exposed learners to visual grammar and visual texts and I collected data around the implementation of the lesson unit as evidenced by journal writing, interviews and non-participant observation. The data revealed that visual literacy could be taught meaningfully in a rural high school as the learners could identify, cut, paste and critically discuss elements of visual language and they finally designed their own advertisements in groups. However, the following factors emerged as hindrances to the successful teaching of visual literacy in this case: lack of resources; learners' lack of a foundation in visual literacy from Grades 7-9; and problems revolving around time management and pacing.
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Date Issued: 2009

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South African music libraries : collegial, institutional and geographic isolation, an examination

- Still-Drewett, F

Authors: Still-Drewett, F
Date: 2009
Language: English
Type: Article
Identifier: vital:6984 , http://hdl.handle.net/10962/d1006723
Description: Music libraries are relatively recent additions to South African library collections and attempts at forming a music library association have been thwarted through a number of financial and historical societal limitations. Consequently, many South African music librarians feel isolated from the field. This paper examines the effects of this isolation and the benefits that closer association for the librarian could bring. Future outlooks for music libraries in South Africa are discussed and suggestions made for a more positive future. Les bibliothèques de musique sont des additions relativement récentes aux collections des bibliothèques en Afrique du sud. Les tentatives de création d'une aßociation de bibliothécaires de musique ont été contrariées pour des raisons financières, historiques et sociales. Par conséquent, beaucoup de bibliothécaires de musique se sentent isolés du milieu. Cet article examine les effets de cette isolation et les bénéfices que pourrait apporter une aßociation qui rapproche les bibliothécaires. Il aborde des discußions sur des perspectives futures et émet des suggestion afin d'appréhender un avenir plus positif. Musikbibliotheken sind eine relativ neue Erscheinung im Bibliothekswesen Südafrikas. Die Gründung einer musikbibliothekarischen Vereinigung ist aus finanziellen und anderen Gründen heraus immer wieder gescheitert. Daher fühlen sich viele südafrikanische Musikbibliothekare beruflich isoliert. Der Artikel untersucht die Auswirkungen dieser Isolation und die Vorteile, die ein engerer Zusammenschluß den Bibliothekaren bringen könnte. Er wagt einen Ausblick in und macht Vorschläge für die Zukunft südafrikanischer Musikbibliotheken.
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Date Issued: 2009

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Spectroscopic and photophysicochemical behaviour of novel cadmium phthalocyanine derivatives tetra-substituted at the alpha and beta positions

- Nyokong, Tebello, Chidawanyika, Wadzanai J U

Authors: Nyokong, Tebello , Chidawanyika, Wadzanai J U
Date: 2009
Language: English
Type: Article
Identifier: vital:6582 , http://hdl.handle.net/10962/d1004147
Description: The syntheses of three cadmium phthalocyanine derivatives tetrakis{1,(4)-(4-benzyloxy)phenoxyphthalocyaninato} (5a), tetrakis{1,(4)-(2-pyridyloxy)phthalocyaninato} (5b) and tetrakis{2,(3)-(4-benzyloxy)phenoxyphthalocyaninato} (6a) are reported here for the first time. Spectroscopic and photophysical properties have also been determined and the results are discussed here paying particular attention to the influence of various organic solvents in relation to the position and type of substitution. Singlet oxygen quantum yields (ΦΔ) and photodegradation quantum yields (ΦPd) have also been discussed. The triplet quantum yields have been determined and ranged from ΦT = 0.36 to 0.85, where the peripherally (β) substituted derivatives generally give higher values than those substituted at the non-peripheral (α) positions. The triplet lifetimes ranged from τT = 5 to 40 μs. In all cases (except toluene, due to the lack of data), the highest singlet oxygen quantum yields obtained were for the pyridyloxy-substituted derivatives 5b (ΦΔ = 0.60 in DMF) and 6b (ΦΔ = 0.74 in DMSO).
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Date Issued: 2009

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Stronger induction of callose deposition in barley by Russian wheat aphid than bird cherry-oat aphid is not associated with differences in callose synthase or ≤-1,3-glucanase expression

- Saheed, Sefiu A, Cierlik, Izabela, Larsson, Kristina A E, Delp, Gabriele, Bradley, Graeme, Jonsson, Lisbeth M V, Botha, Christiaan E J

Authors: Saheed, Sefiu A , Cierlik, Izabela , Larsson, Kristina A E , Delp, Gabriele , Bradley, Graeme , Jonsson, Lisbeth M V , Botha, Christiaan E J
Date: 2009
Language: English
Type: Article
Identifier: vital:6542 , http://hdl.handle.net/10962/d1005984
Description: The effects of infestation by the bird cherry-oat aphid (BCA), (Rhopalosiphum padi L) and the Russian wheat aphid (RWA) (Diuraphis noxia Mordvilko) on callose deposition and gene expression related to callose accumulation were investigated in barley (Hordeum vulgare L. cv. Clipper). The BCA, which gives no visible symptoms, induced very limited callose deposition, even after 14 days of infestation. In contrast, RWA, which causes chlorosis, white and yellow streaking and leaf rolling, induced callose accumulation already after 24h in longitudinal leaf veins. The deposition was pronounced after 72 h, progressing during 7 and 14 days of infestation. In RWA-infested source leaves, callose was also induced in longitudinal veins basipetal to the aphid-infested tissue, whereas in sink leaves, more callose deposition was found above the feeding sites. Nine putative callose synthase genes were identified in a data base search, of which eight were expressed in the leaves, but with similar level of expression in control and aphid-infested tissue. Four out of 12 examined β-1,3-glucanases were expressed in the leaves, and three of them were up-regulated in aphid-infested tissue. They were all more strongly induced by RWA than BCA. The results suggest that callose accumulation may be partly responsible for the symptoms resulting from RWA feeding and that a callose-inducing signal may be transported in the phloem. Furthermore it is concluded that the absence of callose deposition in BCA-infested leaves is not due to a stronger induction of callose-degrading β-1,3-glucanases in this tissue, as compared to RWA-infested leaves.
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Date Issued: 2009

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Suitability of total coliform beta-D-galactosidase activity and CFU counts in monitoring faecal contamination of environmental water samples

- Wutor, V C, Togo, C A, Pletschke, Brett I

Authors: Wutor, V C , Togo, C A , Pletschke, Brett I
Date: 2009
Language: English
Type: Article
Identifier: vital:6477 , http://hdl.handle.net/10962/d1006165 , http://www.scielo.org.za/scielo.php?pid=S1816-79502009000100010&script=sci_arttext
Description: Total coliforms are a group of bacteria found in high numbers in mammalian intestines; hence their presence in water indicates the possible contamination with faecal material. Total and faecal coliform counts were monitored over a period of 18 months using mFC, m-Endo and CM1046 media together with enzymatic assays on 215 environmental water samples obtained from the Eastern Cape Province of South Africa. A positive correlation, with an R2 value of 0.9393 was observed between faecal and total coliform colony units employing mFc and m-Endo media, and 0.8818 using CM1046 media. Also, a positive correlation was observed between Escherichia coli colony-forming units and β-D-galactosidase (B-GAL) activity (R2=0.8542). Overall, this study indicated that faecal contamination of environmental water samples could be monitored by measuring total coliform β-galactosidase activity and total coliform colony-forming units.
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Date Issued: 2009

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Synthesis and Pd(II) binding studies of octasubstituted alkyl thio derivatised phthalocyanines

- Ogunbayo, T B, Nyokong, Tebello

Authors: Ogunbayo, T B , Nyokong, Tebello
Date: 2009
Language: English
Type: Article
Identifier: vital:6587 , http://hdl.handle.net/10962/d1004170
Description: Synthesis and characterization of non-peripherally (4,5) and peripherally (6,7) substituted metal free and Pd octapentylthiophthalocyanine and coordination of palladium ions to these Pcs are reported. The unmetalated complexes (4 and 6) show Pd coordination at the central metal and at the ring. The number of Pd ions bound to complex 4 were found to be five and to complex 6 were three. The equilibrium constant for the binding of Pd to complexes 4 was lower (K = 1.2 × 109 dm3 mol−1) than for complex 6 (K = 5.7 × 1010 dm3 mol−1).
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Date Issued: 2009

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Synthesis of molecularly imprinted polymer for selective solid-phase extraction of Salbutamol from urine samples

- Mohammadi, Ali, Alizadeh, Taher, Dinarvand, Rassoul, Ganjali, Mohammed M, Walker, Roderick B

Authors: Mohammadi, Ali , Alizadeh, Taher , Dinarvand, Rassoul , Ganjali, Mohammed M , Walker, Roderick B
Date: 2009
Language: English
Type: Article
Identifier: vital:6410 , http://hdl.handle.net/10962/d1006496
Description: A highly selective methacrylic based molecularly imprinted polymer (MIP) was synthesized and applied for the separation and the pre-concentration of salbutamol in urine samples. Spectrophotometric determination of salbutamol was achieved using 2,6-dichloroquinone chlorimide as colorimetric reagent. The detection limit of the method was ca. 13 ng/mL in urine after pre-concentration of the samples by MIP-SPE andanalysis with an optimized and sensitive spectrophotometric method. The linear dynamic range for salbutamol determination in urine was 0.04-0.75 μg mL-1. The recovery for the affinity based solid-phase extraction (SPE) with the MIP was more than 96 %.
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Date Issued: 2009

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Synthesis, spectroscopic and electrochemical properties of manganese, nickel and iron octakis-(2-diethylaminoethanethiol)-phthalocyanine

- Adebayo, A I, Nyokong, Tebello

Authors: Adebayo, A I , Nyokong, Tebello
Date: 2009
Language: English
Type: Article
Identifier: vital:6563 , http://hdl.handle.net/10962/d1004122
Description: The syntheses, spectroscopic and electrochemical properties of manganese (3), nickel (4) and iron (5) phthalocyanine complexes, octa-substituted at the peripheral positions with diethlyaminoethanethiol substituent, are reported. The electrochemistry of these complexes and the corresponding cobalt complex (6) are reported. Complex 3 showed two reversible reduction couples attributed to the MnIIIPc−2/MnIIPc−2 (E½ = −0.12 V versus Ag|AgCl) and MnIIPc−2/MnIIPc−3 (E½ = −0.82 V versus Ag|AgCl) species. Two ring-based reduction couples were also observed for complex 4. Two reduction couples, assigned to the FeIIPc−2/FeIPc−2 (E½ = −0.35 V versus Ag|AgCl) and FeIPc−2/FeIPc−3 (E½ = −0.96 V versus Ag|AgCl) species, and an oxidation couple, attributed to FeIIIPc−2/FeIIPc−2 (E½ = 0.26 V versus Ag|AgCl) species, were observed. For complex 6, two reductions and one oxidation were also observed with the potential range of 1.2 to −1.8 V versus Ag|AgCl Spectroelectrochemical studies were used to confirm some of the assigned processes.
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Date Issued: 2009

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The ataxia protein sacsin is a functional co-chaperone that protects against polyglutamine-expanded ataxin-1

- Parfitt, David A, Michael, Gregory J, Vermeulen, Esmeralda G M, Prodromou, Natalia V, Webb, Tom R, Gallo, Jean-Marc, Cheetham, Michael E, Nicoll, William S, Blatch, Gregory L, Chapple, J Paul

Authors: Parfitt, David A , Michael, Gregory J , Vermeulen, Esmeralda G M , Prodromou, Natalia V , Webb, Tom R , Gallo, Jean-Marc , Cheetham, Michael E , Nicoll, William S , Blatch, Gregory L , Chapple, J Paul
Date: 2009
Language: English
Type: Article
Identifier: vital:6485 , http://hdl.handle.net/10962/d1006262 , http://hmg.oxfordjournals.org/content/18/9/1556
Description: An extensive protein–protein interaction network has been identified between proteins implicated in inherited ataxias. The protein sacsin, which is mutated in the early-onset neurodegenerative disease autosomal recessive spastic ataxia of Charlevoix-Saguenay, is a node in this interactome. Here, we have established the neuronal expression of sacsin and functionally characterized domains of the 4579 amino acid protein. Sacsin is most highly expressed in large neurons, particularly within brain motor systems, including cerebellar Purkinje cells. Its subcellular localization in SH-SY5Y neuroblastoma cells was predominantly cytoplasmic with a mitochondrial component. We identified a putative ubiquitin-like (UbL) domain at the N-terminus of sacsin and demonstrated an interaction with the proteasome. Furthermore, sacsin contains a predicted J-domain, the defining feature of DnaJ/Hsp40 proteins. Using a bacterial complementation assay, the sacsin J-domain was demonstrated to be functional. The presence of both UbL and J-domains in sacsin suggests that it may integrate the ubiquitin–proteasome system and Hsp70 function to a specific cellular role. The Hsp70 chaperone machinery is an important component of the cellular response towards aggregation prone mutant proteins that are associated with neurodegenerative diseases. We therefore investigated the effects of siRNA-mediated sacsin knockdown on polyglutamine-expanded ataxin-1. Importantly, SACS siRNA did not affect cell viability with GFP-ataxin-1[30Q], but enhanced the toxicity of GFP-ataxin- 1[82Q], suggesting that sacsin is protective against mutant ataxin-1. Thus, sacsin is an ataxia protein and a regulator of the Hsp70 chaperone machinery that is implicated in the processing of other ataxialinked proteins.
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Date Issued: 2009

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The evaluation of Eudragit microcapsules manufactured by solvent evaporation using USP Apparatus 1

- Khamanga, Sandile M, Parfitt, Natalie R, Nyamuzhiwa, Tsitsi, Haidula, Hendrina, Walker, Roderick B

Authors: Khamanga, Sandile M , Parfitt, Natalie R , Nyamuzhiwa, Tsitsi , Haidula, Hendrina , Walker, Roderick B
Date: 2009
Language: English
Type: text , Article
Identifier: vital:6389 , http://hdl.handle.net/10962/d1006310
Description: The objectives of this study were to prepare microcapsules containing verapamil and propranolol and to evaluate the kinetics and mechanism of drug release from the microcapsules using USP Apparatus 1. The effects of polymer concentration and polymer type on the cumulative amount of drug released were evaluated. The microcapsules were manufactured using Eudragit RS and RL polymers by solvent evaporation with the ultimate aim of prolonging drug release. Twenty-four formulations were prepared using different drug/polymer ratios. The effects of polymer type and polymer/drug ratios on the size, flow properties, surface morphology, and the release characteristics of the microcapsules were examined. The effects of drug inclusion methods on drug loading, encapsulation efficiency, and release properties of the complex microcapsules were also investigated. The formulations containing drug/polymer ratio 1:4 (w/w) were the most appropriate with respect to encapsulation efficiency (70%), flow properties (HR = 1.2), drug loading (15–20%), and drug release characteristics, in all cases. The release kinetics from the different formulations followed mainly a diffusion-controlled mechanism.
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Date Issued: 2009

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The TPR2B domain of the Hsp70/Hsp90 organizing protein (Hop) may contribute towards its dimerization

- Longshaw, Victoria M, Stephens, Linda L, Daniel, Sheril, Blatch, Gregory L

Authors: Longshaw, Victoria M , Stephens, Linda L , Daniel, Sheril , Blatch, Gregory L
Date: 2009
Language: English
Type: Article
Identifier: vital:6481 , http://hdl.handle.net/10962/d1006253 , http://dx.doi.org/10.2174/092986609787848162
Description: The role of the TPR2B domain of Hop is as yet unknown. We have shown here by site directed mutagenesis and size exclusion chromatography for the first time that the TPR1 and TPR2B domains of Hop independently dimerized, and that the dimerization of TPR2B was not dependent on its predicted two-carboxylate clamp residues. Furthermore, our data indicated that the dimerization of Hop and its domains was not disrupted in the presence of Hsp70 and Hsp90 peptides.
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Date Issued: 2009

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The transportability and utility of cognitive therapy in South African contexts: a review

- Young, Charles S

Authors: Young, Charles S
Date: 2009
Language: English
Type: Article
Identifier: vital:6279 , http://hdl.handle.net/10962/d1008280
Description: Cognitive therapy could be more widely promoted in South Africa given the great disparity between the need and provision of psychological therapies. Three possible objections to the promotion of cognitive therapy are considered: uncertainty surrounding the effectiveness of cognitive therapy in South African contexts; uncertainty surrounding the applicability in multicultural contexts; and suggestions that cognitive therapy is decontextualised and therefore objectionable in a country facing major social challenges. A systematic review of the literature indentified 15 outcome studies, and suggests that cognitive therapy is a viable and much-needed approach in South Africa.
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Date Issued: 2009

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The WHO UNESCO FIP Pharmacy Education Taskforce (commentary)

- Anderson, Claire, Bates, Ian, Beck, Diane, Penick Brock, Tina, Futter, William T, Mercer, Hugo, Rouse, Mike, Whitmarsh, Sarah, Wuliji, Tana, Yonemura, Akemi

Authors: Anderson, Claire , Bates, Ian , Beck, Diane , Penick Brock, Tina , Futter, William T , Mercer, Hugo , Rouse, Mike , Whitmarsh, Sarah , Wuliji, Tana , Yonemura, Akemi
Date: 2009
Language: English
Type: Article
Identifier: vital:6347 , http://hdl.handle.net/10962/d1006020
Description: Pharmacists' roles are evolving from that of compounders and dispensers of medicines to that of experts on medicines within multidisciplinary health care teams. In the developing country context, the pharmacy is often the most accessible or even the sole point of access to health care advice and services. Because of their knowledge of medicines and clinical therapeutics, pharmacists are suitably placed for task shifting in health care and could be further trained to undertake functions such as clinical management and laboratory diagnostics. Indeed, pharmacists have been shown to be willing, competent, and cost-effective providers of what the professional literature calls "pharmaceutical care interventions"; however, internationally, there is an underuse of pharmacists for patient care and public health efforts. A coordinated and multifaceted effort to advance workforce planning, training and education is needed in order to prepare an adequate number of well-trained pharmacists for such roles. Acknowledging that health care needs can vary across geography and culture, an international group of key stakeholders in pharmacy education and global health has reached unanimous agreement that pharmacy education must be quality-driven and directed towards societal health care needs, the services required to meet those needs, the competences necessary to provide these services and the education needed to ensure those competences. Using that framework, this commentary describes the Pharmacy Education Taskforce of the World Health Organization, United Nations Educational, Scientific and Cultural Organization and the International Pharmaceutical Federation Global Pharmacy and the Education Action Plan 2008–2010, including the foundation, domains, objectives and outcome measures, and includes several examples of current activities within this scope.
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Date Issued: 2009

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Topographic thresholds in gully development on the hillslopes of communal areas in Ngqushwa Local Municipality, Eastern Cape, South Africa

- Kakembo, V, Xanga, W W, Rowntree, Kate M

Authors: Kakembo, V , Xanga, W W , Rowntree, Kate M
Date: 2009
Language: English
Type: Article
Identifier: vital:6691 , http://hdl.handle.net/10962/d1006726
Description: The relationships between the spatial distribution of gully erosion and topographic thresholds in the form of slope angle, position and configuration, as well as land use change in the form of abandoned lands were examined in several affected catchments of the Eastern Cape Province, South Africa. Land use and permanent gullies were mapped, digitized from orthophoto maps in Arc/info 3.5.2 GIS and converted to shapefiles using ArcView 3.2 GIS. Relationships between the mapped phenomena and topographic variables were sought using a Digital Elevation Model (DEM) in Idrisi Kilimanjaro GIS. A comparison between areas with a high potential for gullying and actual gully erosion was made using the Stream Power Index (SPI) as a surrogate for critical flow shear stress. Field surveys were also conducted to assess the present condition of the gullied sites as well as to validate DEM derivations. Seventy five percent of the gullied area was noted to lie on abandoned lands. A predominance of gullying in concave bottom lands was also identified. The SPI values highlighted a distinct preferential topographic zone for gully location. A conceptual model depicting the interaction between land use and topographic parameters to induce gully erosion was developed. This should assist local authorities to develop a policy regarding management of abandoned lands.
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Date Issued: 2009

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Towards a GPS-based TEC prediction model for Southern Africa with feed forward networks

- Habarulema, John B, McKinnell, Lee-Anne, Opperman, Ben D L

Authors: Habarulema, John B , McKinnell, Lee-Anne , Opperman, Ben D L
Date: 2009
Language: English
Type: text , Article
Identifier: vital:6806 , http://hdl.handle.net/10962/d1004192
Description: In this paper, first results from a national Global Positioning System (GPS) based total electron content (TEC) prediction model over South Africa are presented. Data for 10 GPS receiver stations distributed through out the country were used to train a feed forward neural network (NN) over an interval of at most five years. In the NN training, validating and testing processes, five factors which are well known to influence TEC variability namely diurnal variation, seasonal variation, magnetic activity, solar activity and the geographic position of the GPS receivers were included in the NN model. The database consisted of 1-min data and therefore the NN model developed can be used to forecast TEC values 1 min in advance. Results from the NN national model (NM) were compared with hourly TEC values generated by the earlier developed NN single station models (SSMs) at Sutherland (32.38°S, 20.81°E) and Springbok (29.67°S, 17.88°E), to predict TEC variations over the Cape Town (33.95°S, 18.47°E) and Upington (28.41°S, 21.26°E) stations, respectively, during equinoxes and solstices. This revealed that, on average, the NM led to an improvement in TEC prediction accuracy compared to the SSMs for the considered testing periods.
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Date Issued: 2009

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Treating posttraumatic stress disorder in South Africa : an integrative model grounded in case-based research

- Edwards, David J A

Authors: Edwards, David J A
Date: 2009
Language: English
Type: Article
Identifier: vital:6232 , http://hdl.handle.net/10962/d1007782
Description: The article presents a model for formulating and planning treatment for post-traumatic stress disorder (PTSD) in South Africa derived from the existing literature and in conjunction with a review of a series of studies of cases treated using the guidelines of Ehlers and Clark's cognitive therapy. It is argued that the construction of psychotherapies (or even components of psychotherapy) for PTSD in terms of traditional categories ("psychodynamic", "cognitive-behavioural", "narrative" etc.) is misleading and unhelpful. Instead, superordinate concepts derived from thinking about evidence-based practice provide a more grounded focus on the practical issues faced by therapists treating PTSD. These concepts, which include competences and metcacompetences, therapist responsiveness, stages of therapy and case formulation, provide a basis for a genuinely integrative approach. The proposed model suggests seven broad areas of clinical focus for work with PTSD which can be arranged at three levels of priority: level 1 crisis intervention and stabilization; level 2 promoting engagement with treatment, and level 3 selection, sequencing and timing of active treatment interventions. Material from the case series is used to illustrate the application of the model.
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Date Issued: 2009

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Tri-locus sequence data reject a Gondwanan origin hypothesis for the African/South Pacific crab genus Hymenosoma

- Teske, Peter R, McLay, Colin L, Sandoval-Castillo, Jonathan, Papadopoulos, Isabelle, Newman, Brent K, Griffiths, Charles L, McQuaid, Christopher D, Barker, Nigel P, Borgonie, Gaetan, Beheregaray, Luciano B

Authors: Teske, Peter R , McLay, Colin L , Sandoval-Castillo, Jonathan , Papadopoulos, Isabelle , Newman, Brent K , Griffiths, Charles L , McQuaid, Christopher D , Barker, Nigel P , Borgonie, Gaetan , Beheregaray, Luciano B
Date: 2009
Language: English
Type: Article
Identifier: vital:6547 , http://hdl.handle.net/10962/d1006003
Description: Crabs of the family Hymenosomatidae are common in coastal and shelf regions throughout much of the southern hemisphere. One of the genera in the family, Hymenosoma, is represented in Africa and the South Pacific (Australia and New Zealand). This distribution can be explained either by vicariance (presence of the genus on the Gondwanan supercontinent and divergence following its break-up) or more recent transoceanic dispersal from one region to the other. We tested these hypotheses by reconstructing phylogenetic relationships among the seven presently-accepted species in the genus, as well as examining their placement among other hymenosomatid crabs, using sequence data from two nuclear markers (Adenine Nucleotide Transporter [ANT] exon 2 and 18S rDNA) and three mitochondrial markers (COI, 12S and 16S rDNA). The five southern African representatives of the genus were recovered as a monophyletic lineage, and another southern African species, Neorhynchoplax bovis, was identified as their sister taxon. The two species of Hymenosoma from the South Pacific neither clustered with their African congeners, nor with each other, and should therefore both be placed into different genera. Molecular dating supports a post-Gondwanan origin of the Hymenosomatidae. While long-distance dispersal cannot be ruled out to explain the presence of the family Hymenosomatidae on the former Gondwanan land-masses and beyond, the evolutionary history of the African species of Hymenosoma indicates that a third means of speciation may be important in this group: gradual along-coast dispersal from tropical towards temperate regions, with range expansions into formerly inhospitable habitat during warm climatic phases, followed by adaptation and speciation during subsequent cooler phases.
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Date Issued: 2009

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