Histological confirmation of epizootic ulcerative syndrome in two cyprinid species from Lake Liambezi, Zambezi Region, Namibia
- Authors: McHugh, Kyle J , Smit, Nico J , Christison, Kevin W , Weyl, Olaf L F
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443354 , vital:74110 , https://hdl.handle.net/10520/EJC160489
- Description: Epizootic ulcerative syndrome (EUS) is a fish disease caused by an infection of the oomycete, Aphanomyces invadans. During a fish biodiversity assessment of Lake Liambezi, Zambezi Region, Namibia, in August 2011, two Barbus haasianus and three Barbus unitaeniatus with circular ulcerative skin lesions were collected. Lake Liambezi receives inflow from the Zambezi, Chobe and Linyanti rivers. The presence of EUS in the two species was confirmed histologically by: a loss of epidermis at the site of the lesion; hyphae visible deep into the muscle layer with an associated granulomatous inflammatory reaction; and muscle fibre degeneration visible with associated penetrating hyphae. This paper provides further histological confirmation of EUS from Lake Liambezi and the first record of the disease in B. haasianus.
- Full Text:
- Date Issued: 2014
Homestead greening is widespread amongst the urban poor in three medium-sized South African towns
- Authors: Kaoma, Humphrey , Shackleton, Charlie M
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/398291 , vital:69398 , xlink:href="https://doi.org/10.1007/s11252-014-0362-3"
- Description: Trees in urban areas are important sources of ecosystem services and benefits. In most towns the bulk of urban biodiversity, and trees specifically, are found in homestead gardens. But there is only limited understanding of the tree holdings in such gardens, and how they vary within and between towns, especially for developing countries where rapid urbanisation and high poverty influence the use of and reliance on land and local resources. We report on the nature of tree holdings in private gardens of poorer suburbs in three medium-sized towns along a gradient of decreasing mean annual rainfall in northern South Africa. A total of 3 217 trees were enumerated across 450 randomly selected homesteads. Most (90 %) households had at least one tree on their homestead, with an average of 7.7 ± 6.1 trees. Most householders had planted the trees themselves. The density of trees declined along the moisture gradient. Within towns, tree density was positively related to garden size, which in turn was related to relative affluence and age of the suburb. Newer and poorer suburbs had the fewest trees per household. Sixty-two tree species were recorded, which were dominated by alien species, especially fruit trees. There was no relationship between the moisture gradient and tree species richness per household, but within towns there was a difference between suburbs, being lowest in the newest suburbs. Numbers of trees and species per household was positively related to age of the household head.
- Full Text:
- Date Issued: 2014
HPLC method for simultaneous analysis of ranitidine and metronidazole in dosage forms
- Authors: King'ori, Loti D , Walker, Roderick B
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/184790 , vital:44272 , xlink:href="https://doi.org/10.14233/ajchem.2014.15432"
- Description: A simple, rapid, precise and accurate stability indicating HPLC method for the simultaneous analysis of metronidazole and ranitidine in dosage forms has been developed and validated. Calibration curves for metronidazole and ranitidine exhibited linearity (R2 = 0.9995 for both compounds) over the concentration ranges investigated. The method was sensitive, selective and accurate for both compounds. Both drugs were found to be stable following acid hydrolysis studies. However, following alkali hydrolysis degradation of both compounds was observed. Furthermore metronidazole appeared to be stable following oxidative studies however ranitidine underwent complete degradation under these conditions. Both drugs were well resolved from the degradation products. The stability indicating chromatographic method has the necessary precision and accuracy for the simultaneous analysis of metronidazole and ranitidine in dosage forms.
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- Date Issued: 2014
Hsp90 binds directly to fibronectin (FN) and inhibition reduces the extracellular fibronectin matrix in breast cancer cells
- Authors: Hunter, Morgan C , O’Hagan, Kyle L , Kenyon, Amy , Dhanani, Karim C H , Prinsloo, Earl , Edkins, Adrienne L
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431143 , vital:72748 , xlink:href="https://doi.org/10.1371/journal.pone.0086842"
- Description: Heat shock protein 90 (Hsp90) has been identified in the extracellular space and has been shown to chaperone a finite number of extracellular proteins involved in cell migration and invasion. We used chemical cross-linking and immunoprecipitation followed by tandem mass spectrometry (MS/MS) to isolate a complex containing Hsp90 and the matrix protein fibronectin (FN) from breast cancer cells. Further analysis showed direct binding of Hsp90 to FN using an in vitro co-immunoprecipitation assay, a solid phase binding assay and surface plasmon resonance (SPR) spectroscopy. Confocal microscopy showed regions of co-localisation of Hsp90 and FN in breast cancer cell lines. Exogenous Hsp90β was shown to increase the formation of extracellular FN matrix in the Hs578T cell line, whilst knockdown or inhibition of Hsp90 led to a reduction in the levels of both soluble and insoluble FN and could be partially rescued by addition of exogenous Hsp90β. Treatment of cells with novobiocin led to internalization of FN into vesicles that were positive for the presence of the lysosomal marker, LAMP-1. Taken together, the direct interaction between FN and Hsp90, as well as the decreased levels of both soluble and insoluble FN upon Hsp90 inhibition or knockdown, suggested that FN may be a new client protein for Hsp90 and that Hsp90 was involved in FN matrix assembly and/or stability. The identification of FN as a putative client protein of Hsp90 suggests a role for Hsp90 in FN matrix stability, which is important for a number of fundamental cellular processes including embryogenesis, wound healing, cell migration and metastasis.
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- Date Issued: 2014
Human perception of the measurement of a network attack taxonomy in near real-time
- Authors: Van Heerden, Renier , Malan, Mercia M , Mouton, Francois , Irwin, Barry V W
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/429924 , vital:72652 , https://doi.org/10.1007/978-3-662-44208-1_23
- Description: This paper investigates how the measurement of a network attack taxonomy can be related to human perception. Network attacks do not have a time limitation, but the earlier its detected, the more damage can be prevented and the more preventative actions can be taken. This paper evaluate how elements of network attacks can be measured in near real-time(60 seconds). The taxonomy we use was developed by van Heerden et al (2012) with over 100 classes. These classes present the attack and defenders point of view. The degree to which each class can be quantified or measured is determined by investigating the accuracy of various assessment methods. We classify each class as either defined, high, low or not quantifiable. For example, it may not be possible to determine the instigator of an attack (Aggressor), but only that the attack has been launched by a Hacker (Actor). Some classes can only be quantified with a low confidence or not at all in a sort (near real-time) time. The IP address of an attack can easily be faked thus reducing the confidence in the information obtained from it, and thus determining the origin of an attack with a low confidence. This determination itself is subjective. All the evaluations of the classes in this paper is subjective, but due to the very basic grouping (High, Low or Not Quantifiable) a subjective value can be used. The complexity of the taxonomy can be significantly reduced if classes with only a high perceptive accuracy is used.
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- Date Issued: 2014
Improved l-cysteine electrocatalysis through a sequential drop dry technique using multi-walled carbon nanotubes and cobalt tetraaminophthalocyanine conjugates
- Authors: Nyoni, Stephen , Mugadza, Tawanda , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193813 , vital:45398 , xlink:href="https://doi.org/10.1016/j.electacta.2013.10.023"
- Description: Voltammetry, chronoamperometry, scanning electrochemical microscopy and electrochemical impedance spectroscopy methods are used for characterization of a glassy carbon electrode modified with multi-walled carbon nanotubes (MWCNTs)–cobalt tetraaminophthalocyanine (CoTAPc) mixture or sequential drop dry modification technique whereby the MWCNTs are first placed on to the electrode followed by CoTAPc. The sequential drop dry CoTAPc–MWCNTs modified surface gave better catalytic responses with a catalytic rate constant of 2.2 × 105 M−1 s−1, apparent electron transfer rate constant of 0.073 cm s−1, and a limit of detection of 2.8 × 10−7 M. Scanning electrochemical microscopy (SECM) surface characterization (topography and reactivity) further gave proof the better catalytic perfomance of the sequential drop dry CoTAPc–MWCNTs modified surface.
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- Date Issued: 2014
Indium phthalocyanine–CdSe/ZnS quantum dots nanocomposites showing size dependent and near ideal optical limiting behaviour
- Authors: Sanusi, Kayode , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189921 , vital:44947 , xlink:href="https://doi.org/10.1016/j.optmat.2014.09.021"
- Description: Indium phthalocyanine–CdSe/ZnS quantum dots (QDs) nanocomposites (InPc–CdSe/ZnS) of three sizes (5.57, 8.12 and 8.75 nm) were synthesized according to known procedures. The particle size of the CdSe/ZnS QDs alone are 3.95, 6.02, and 6.66 nm, and are denoted as QD1, QD2 and QD3 respectively. The nonlinear absorption (NLA) properties of the nanoconjugates (InPc–CdSe/ZnS) were investigated with nanosecond laser radiation at 532 nm wavelength. Enhanced NLA properties compared to the InPc alone were observed in the conjugates. The NLA was found to increase with the size of the CdSe/ZnS particles attached to the phthalocyanine. The observed increase was due to the availability of more free-carrier ions in the larger QDs, thus giving rise to the enhanced free-carrier absorption. The measured free-carrier absorption cross-sections (σFCA) are 1.10, 1.65 and 1.95 (×10−19 cm2) for InPc-QD1, InPc-QD2 and InPc-QD3 respectively. The nanoconjugates (InPc–CdSe/ZnS) showed a much lower threshold for optical limiting together with a much lower transmission at high fluences, than the previously reported nanocomposite limiters.
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- Date Issued: 2014
Informing the Responses of Water Service Delivery Institutions to Climate and Development Changes: A Case Study in the Amatole Region, Eastern Cape
- Authors: Hughes, Denis A , Mantel, Sukhmani K , Slaughter, Andrew R
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , report
- Identifier: http://hdl.handle.net/10962/438140 , vital:73438 , ISBN 978-1-4312-0520-2 , https://wrcwebsite.azurewebsites.net/wp-content/uploads/mdocs/2018-1-14.pdf
- Description: This report has been generated by the Water Research Commission (WRC) funded project Developing Climate Change Adaptation Measures and Decision-Support System for Selected South African Water Boards (Project No. K5/2018).
- Full Text:
- Date Issued: 2014
Invasive alien species as drivers in socio-ecological systems: Local adaptations towards use of Lantana in Southern India
- Authors: Kannan, Ramesh , Shackleton, Charlie M , Shaanker, Ramanan U
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180932 , vital:43671 , xlink:href="https://doi.org/10.1007/s10668-013-9500-y"
- Description: Lantana camara. L (hereafter Lantana) was first introduced by the British into India in 1807 as an ornamental plant. Since then the species has spread across the length and breadth of the country. Attempts to control Lantana in India have not been successful. In this study, we analysed the use of Lantana by local communities in southern India and identified the possible causes and consequences of its use through the use of a household survey of the socio-economic profile of the user and nonuser households and an analysis of the ecological history of the communities. Communities have been using Lantana for over 25–30 years and apparently such use was not prompted by external agencies. The characteristics of user and nonuser households were similar, except that Lantana users were more literate and had a greater number of occupations per household than nonusers. Per capita income was similar between user and nonuser groups. For nonuser groups, their main income sources were from trading (44 %), wage labour (32 %) and forest resources (23 %). In contrast, the Lantana user groups substituted their loss of income from forest resources (7 %) by income from Lantana (46 %). The ecological history revealed that Lantana was adopted as a resource at a time when it was increasing in the landscape and traditional bamboo resources were in decline because of overuse by commercial enterprises and mast flowering. This change in ecological resource availability prompted a major shift in livelihoods for some in the area.
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- Date Issued: 2014
Investigating the chaperone properties of a novel heat shock protein, Hsp70. c, from Trypanosoma brucei
- Authors: Burger, Adélle , Ludewig, Michael H , Boshoff, Aileen
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/431155 , vital:72749 , xlink:href="https://doi.org/10.1155/2014/172582"
- Description: The neglected tropical disease, African Trypanosomiasis, is fatal and has a crippling impact on economic development. Heat shock protein 70 (Hsp70) is an important molecular chaperone that is expressed in response to stress and Hsp40 acts as its co-chaperone. These proteins play a wide range of roles in the cell and they are required to assist the parasite as it moves from a cold blooded insect vector to a warm blooded mammalian host. A novel cytosolic Hsp70, from Trypanosoma brucei, TbHsp70.c, contains an acidic substrate binding domain and lacks the C-terminal EEVD motif.The ability of a cytosolic Hsp40 from Trypanosoma brucei J protein 2, Tbj2, to function as a co-chaperone of TbHsp70.c was investigated.The main objective was to functionally characterize TbHsp70.c to further expand our knowledge of parasite biology. TbHsp70.c and Tbj2 were heterologously expressed and purified and both proteins displayed the ability to suppress aggregation of thermolabile MDH and chemically denatured rhodanese. ATPase assays revealed a 2.8-fold stimulation of the ATPase activity of TbHsp70.c by Tbj2. TbHsp70.c and Tbj2 both demonstrated chaperone activity and Tbj2 functions as a co-chaperone of TbHsp70.c.In vivo heat stress experiments indicated upregulation of the expression levels of TbHsp70.c.
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- Date Issued: 2014
Investigations of growth metrics and δ15N values of water hyacinth (Eichhornia crassipes,(Mart.) Solms-Laub) in relation to biological control
- Authors: Hill, Jaclyn M
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444758 , vital:74265 , https://doi.org/10.1016/j.aquabot.2013.12.001
- Description: The success of biological control for Eichhornia crassipes (Mart) Solms-Laub has been varied, with failure attributed to various factors including increased eutrophication in freshwater systems. Studies have shown that high N-loads are associated with enriched δ15N values of aquatic biota. Stable isotope analyses may help to assess the nutrient status of invaded ecosystems and predict the success of classical biological control. A combination of controlled greenhouse experiments and in situ observations were used to quantify the δ15N equilibration rate of E. crassipes leaf tissue (i.e. the time span of the information on environmental N-loading), confirm the ability of plant tissue to reflect ecosystem N-loading and to compare standard water hyacinth growth metrics with δ15N and C/N ratios to evaluate how well they described eutrophication. Using both δ15N values and C/N ratios, it was possible to clearly distinguish between manure, fertilizer and control regimes and plant tissue provided information on ecosystem N loading over approximately 16 days.
- Full Text:
- Date Issued: 2014
ISSRs indicate that Chromolaena odorata invading southern Africa originates in Jamaica or Cuba
- Authors: Paterson, Iain D , Zachariades, Coastas
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406105 , vital:70239 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.04.005"
- Description: Two biotypes of the invasive alien plant, Chromolaena odorata (L.) R.M. King and Rob. (Asteraceae: Eupatorieae), are recognized in the plant’s introduced distribution. The Asian/West African (A/WA) biotype is present in West and Central Africa, India, Southeast Asia and Oceania, while the southern African (SA) biotype is only present in southern Africa. Biological control using insect natural enemies has been significantly more successful against the A/WA biotype than the SA biotype, suggesting that host plant incompatibility may have resulted in reduced efficacy of biological control agents in southern Africa. Inter-Simple Sequence Repeats (ISSR) were used to identify the origin of the SA biotype as Jamaica or Cuba. The data also confirm that the SA biotype is genetically distinct from the A/WA biotype and that the SA biotype is the result of a separate introduction. Biological control agents for C. odorata in southern Africa should be sourced from Jamaica and Cuba in order to avoid host plant incompatibility problems.
- Full Text:
- Date Issued: 2014
Kalaharituber pfeilii and associated bacterial interactions
- Authors: Adeleke, Rasheed , Dames, Joanna F
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/440490 , vital:73787 , https://doi.org/10.1016/j.sajb.2013.10.003
- Description: Truffles are generally known to form a mycorrhizal relationship with plants. Kalaharituber pfeilii (Hennings) Trappe and Kagan-Zur is a species of desert truffle that is found in the southern part of Africa. The life cycle of this truffle has not been fully investigated as there are many unconfirmed plant species that have been suggested as potential hosts. Many mycorrhizal associations often involve other role players such as associated bacteria that may influence the establishment of the mycorrhizal formation and function. As part of an effort to understand the life cycle of K. pfeilii, laboratory experiments were conducted to investigate the role of ascocarp associated bacteria. Bacterial isolates obtained from the truffle ascocarps were subjected to microbiological and biochemical tests to determine their potentials as mycorrhizal helper bacteria. Tests conducted included stimulation of mycelial growth in vitro, indole acetic acid (IAA) production and phosphate solubilising. A total of 17 bacterial strains belonging to the Proteobacteria, Firmicutes and Actinobacteria were isolated from the truffle ascocarps and identified with sequence homology and phylogenetic methods. Three of these isolates showed potential to be helper bacteria in at least one of the media tested through the stimulation of mycelial growth. Furthermore, four isolates produced IAA and one was able to solubilise CaHPO3 in vitro. One isolate, identified as a relative of Paenibacillus sp. stimulated mycelial growth on all the media tested. Other bacterial isolates that showed potential stimulation of mycelial growth were identified molecularly as a Bacillus sp. and two strains of Rhizobium sp. This study has contributed to the existing knowledge on the biotic interactions with K. pfeilii which may be useful in further symbiont and re-synthesis investigations.
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- Date Issued: 2014
Leadership for biodiversity in South Africa transformation and capacity development in the GreenMatter programme
- Authors: Rosenberg, Eureta
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437190 , vital:73351 , ISBN 978-9086862528 , https://doi.org/10.3920/978-90-8686-802-5_18
- Description: As we begin to write this chapter, it is only a few hours since the news broke about the passing of Nelson Mandela, the founding president of a democratic South Africa. As we de-scribe our work in supporting intergenerational learning and the development of transformational leadership, it seems appro-priate to make this reference as a tribute to him. This work would not have been possible without the contribution of Man-dela and all who fought for justice and an egalitarian society in South Africa. We are able to write about the so-called ‘born frees’ because of Mandela’s role in dismantling apartheid, a system that sought to condemn black people to perpetual ser-vitude, ignorance and poverty. Indeed, our efforts in building skills for biodiversity, under the auspices of GreenMatter, are inspired by his courageous leadership, his selflessness, com-mitment to education and love of people, knowledge and na-ture. While philosophies, contexts and methods will vary, the quest of all intergenerational learning is to build a bridge that enables young people to learn from the experiences and wisdom of previous generations.
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- Date Issued: 2014
Lever Brothers & Unilever – a practical problem of source?
- Authors: Stack, Elizabeth M , Grenville, D P , Poole, Richard , Horn, Edward B , Harnett, Hugh N
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/2143 , vital:20259
- Full Text:
- Date Issued: 2014
Life satisfaction and education in South Africa: Investigating the role of attainment and the likelihood of education as a positional good
- Authors: Botha, Ferdi
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396091 , vital:69149 , xlink:href="https://doi.org/10.1007/s11205-013-0452-2"
- Description: This paper explores various dynamics in the relationship between life satisfaction and education in South Africa using the 2008 National Income Dynamics Survey. The results indicate a strong positive association between educational attainment and individual satisfaction with life, which is true in the overall sample and for men and women. This positive relationship also holds for Black and Coloured individuals, but is insignificant in the Asian and White samples. Evidence indicates that education is a positional good, in that people who have attained more than the mean level of education in their relevant cluster are significantly more satisfied with life compared to those possessing less than the mean education.
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- Date Issued: 2014
Life-history characteristics of an age-validated established invasive African sharptooth catfish, Clarias gariepinus, population in a warm-temperate African impoundment
- Authors: Wartenberg, Reece , Weyl, Olaf L F , Booth, Anthony J , Winker, Henning
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443542 , vital:74130 , https://hdl.handle.net/10520/EJC145790
- Description: It has been suggested that the invasive, omnivorous Clarias garipienus is capable of rapid invasions and long-term persistence in recently inhabited freshwater systems. To test this hypothesis, the life history of the established, extralimital Darlington Dam (33°10'31"S, 25°09'13"E) population was investigated. By counting post-fluorescent mark increments on otoliths from 21 chemically tagged wild fish recaptured 244-537 days later, the deposition of growth zones, comprising alternating opaque and translucent bands, was validated as annual. Examination of sectioned otoliths from 175 fish revealed that the oldest fish, two males of 840 and 1074 mm total length (TL), were 25 years old - 10 years older than previously described for any C. gariepinus population. The oldest female was 885 mm TL and 21 years old. Length-at-age was subsequently described using the von Bertalanffy growth model. Combined-sex growth was best described as Lt = 931.7 ( 1 - exp(-0.15(t +2.43))) mm TL. Total mortality (Z) was calculated using catch curve analysis and the Chapman and Robson estimator to be 0.35/yr. The presence of specimens 15 years and older indicates that these fish established quickly and supports the finding that mortality rates are low, which, in turn, suggests likely long-term population persistence.
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- Date Issued: 2014
Low-cost housing developments in South Africa miss the opportunities for household level urban greening
- Authors: Shackleton, Charlie M , Hebinck, Paul , Kaoma, Humphrey , Chishaleshale, Mwale , Chinyimba, Abby , Shackleton, Sheona E , Gambiza, James , Gumbo, Davison
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180967 , vital:43677 , xlink:href="https://doi.org/10.1016/j.landusepol.2013.10.002"
- Description: Most developing countries of the world are experiencing large-scale migration from rural to urban areas. Many new migrants end up in low-cost or informal areas and slums with attendant environmental concerns. One dimension of improved urban sustainability is the provision of green spaces and trees. Whilst many countries have urban greening programmes for public spaces and streets, few have considered the status and potential contribution of trees from resident's own gardens. This paper reports firstly on the policy environment for urban forestry and greening in South Africa and secondly on the maintenance, use and appreciation of trees on private homesteads of residents of new and older low-income suburbs as well as informal housing areas from three small towns in South Africa. In particular we examine if the most recent centrally planned and built low-income housing schemes (called RDP suburbs in South Africa) have considered and incorporated plans or spaces for urban greenery in peoples’ homesteads. We found that broad environmental and sustainability concerns and statements are common in urban development and housing policies, but specific guidelines for implementation are generally absent. More specifically, urban forestry and tree planting are rarely mentioned in the broader land use and environmental policies other than the national forest act and subsequent regulations, but even there it is relatively superficial. In the study towns the prevalence, density and number of species of trees was lowest in the new RDP suburbs relative to the township and informal areas. Consequently, the contribution of tree products to local livelihoods was also lower in the RDP areas. Yet there were no differences in the level of appreciation of the value and intangible benefits of trees between residents from the three different suburbs. This shows that the failure to plan for and accommodate trees in new low-cost housing developments is missing an opportunity to improve overall urban sustainability and liveability and constraining the potential flows of tangible and intangible benefits to urban residents. Making opportunities for such in older suburbs is challenging because of space limitations and cost implications of retrospective provisions, but incorporation into plans for new low-cost housing development should be possible.
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- Date Issued: 2014
Mitonuclear discordance in genetic structure across the Atlantic/Indian Ocean biogeographical transition zone
- Authors: Teske, Peter R , Papadopoulos, Isabelle , Barker, Nigel P , McQuaid, Christopher D , Beheregaray, Luciano B
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/444832 , vital:74301 , https://doi.org/10.1111/jbi.1220
- Description: Based on mitochondrial DNA (mtDNA) data, many organisms with ranges spanning multiple biogeographical regions exhibit genetic structure across the transition zones between these regions, while others appear to be genetically homogenous. No clear link has been found between the presence or absence of such spatial genetic discontinuities and species' dispersal potential, confounding the formulation of general predictions concerning genetic structure. The fact that discrepancies between mtDNA and nuclear markers are common across semi‐permeable barriers suggests that a lack of structure could be attributable to mtDNA‐specific properties of inheritance. We re‐examined genetic structure in the coastal crab Hymenosoma orbiculare, a species that is represented by a single mtDNA lineage across the Atlantic/Indian Ocean biogeographical transition zone, by comparing mtDNA data with nuclear DNA data.
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- Date Issued: 2014
Morphological identification of Lucilia sericata, Lucilia cuprina and their hybrids (Diptera, Calliphoridae)
- Authors: Williams, Kirstin A , Villet, Martin H
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441476 , vital:73892 , https://zookeys.pensoft.net/articles.php?id=3908
- Description: Hybrids of Lucilia sericata and Lucilia cuprina have been shown to exist in previous studies using molecular methods, but no study has shown explicitly that these hybrids can be identified morphologically. Published morphological characters used to identify L. sericata and L. cuprina were reviewed, and then scored and tested using specimens of both species and known hybrids. Ordination by multi-dimensional scaling indicated that the species were separable, and that hybrids resembled L. cuprina, whatever their origin. Discriminant function analysis of the characters successfully separated the specimens into three unambiguous groups – L. sericata, L. cuprina and hybrids. The hybrids were morphologically similar irrespective of whether they were from an ancient introgressed lineage or more modern. This is the first evidence that hybrids of these two species can be identified from their morphology. The usefulness of the morphological characters is also discussed and photographs of several characters are included to facilitate their assessment.
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- Date Issued: 2014