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Education in the Anthropocene: Ethico-moral dimensions and critical realist openings

  • Authors: Olvitt, Lausanne L
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/372753 , vital:66620 , xlink:href="https://doi.org/10.1080/03057240.2017.1342613"
  • Description: Human-induced changes in planetary bio-geo-chemical processes have tipped earth into a newly-proposed geological epoch: the Anthropocene, which places moral and ethical demands on people regarding who should take responsibility for the well-being of people and planet, how, and why. Drawing generally on critical realist ontology, and more particularly on Roy Bhaskar’s concept of the person as a ‘four-planar social being’ living in the world as a laminated ontological whole, the article examines the dimensions of people’s ethico-moral engagement with the Anthropocene and considers what types of learning processes might enable people to understand, live in, and co-create this period known as ‘the Anthropocene’ in just, care-filled and—where necessary—transformative ways. The article points to the need for a radical re-orientation of education systems in the light of ethico-moral challenges that come to prominence in the Anthropocene, and argues for learning processes that nurture individual and collective moral agency through transformative, even transgressive, learning processes that are relational, humble, interdisciplinary, multi-perspectival, systemic, reality-congruent and contextually responsive.
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  • Date Issued: 2017

Effect of graphitization on the static mechanical properties of service exposed ASTM A516 Gr. 65 steam pipe metal

  • Authors: Du Preez, Christiaan
  • Date: 2017
  • Subjects: Graphitization Steam-pipes -- Mechanical properties
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/22277 , vital:29933
  • Description: The focus of this research project is to establish what effect graphitization has on the static mechanical properties of service exposed ASTM A516 Grade 65 steam pipe material, which operated for prolonged periods above 425 ̊C. The research study was conducted on three graphitized service exposed steam pipe weldment samples and on a newly welded and post weld heat treated sample with graphitized service exposed steam pipe material. Macro samples were removed from each of the samples at two positions and these were evaluated with regard to graphite nodule size, nearest neighbour spacing and % planar graphitization in the parent pipe and HAZ regions on either side of the welds. It was found on all of the service exposed samples that the graphite nodules of the HAZ regions have a smaller median nodule size, smaller median nearest neighbour spacing and increased % planar graphitization in comparison to the parent pipe material. The service expose parent pipe material on either side of the weldments of the respective samples was chemically analyzed. This was done with the focus being on the deoxidizing element content (Si and Al) of the respective parent pipe regions and to what extent these elements influenced the development of planar graphitization in these regions. No correlation could be identified between the level of deoxidizing elements and the levels of % planar graphitization in the parent pipe material. Tensile and Charpy impact samples were removed from the respective service exposed samples parent material on either side of the weld and from the HAZ regions on the side with the highest levels of planar graphitization. These samples were tested and the yield and ultimate tensile strength and Charpy impact toughness of the respective samples were then evaluated to establish how these static mechanical properties were influenced by the % planar graphitization. The yield and ultimate tensile strength of the service exposed material did not show a statistically significant correlation with the % planar graphitization. The Charpy impact toughness results did however show a statistically significant negative correlation towards the % planar graphitization. This was clearly evident from the results of the HAZ regions of the service exposed weldments (Samples A-C) which had the highest levels of % planar graphitization and the lowest impact toughness, while the newly welded and post weld heat treated Sample D had no planar graphitization outside the HAZ and the highest impact toughness. This research project not only investigated how planar graphitization affects the static mechanical properties of service exposed pipe material, it also investigated on a microstructural basis, how planar graphitization nucleates and grows. The microstructural investigation showed that the free carbon required for the development of planar graphitization originated from the regions outside the HAZ, which were formed when the pearlite bands were dissolved during the welding of the steam pipe. The heat input from the welding sensitized this region for the development of planar graphitization, probably due to the formation of a “carbon-rich” matrix due to the partial dissolution of the cementite precipitates. All the carbide precipitates in this region consisted of M3C. aluminium-rich precipitates were found inside newly nucleated graphite nodules, indicating its role as a possible heterogeneous nucleation site. Growth of newly formed graphite nodules showed a preference towards high-angle grain boundaries and regions with dislocations for the initial growth stages of the graphite nodules. The microstructure of the region outside the HAZ of the newly introduced seam weld on the service exposed steam pipe material (with graphitization), was also investigated using advanced electron microscopy methods and it yielded no evidence of the development of planar graphitization.
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  • Date Issued: 2017

Effecting social justice during conciliation and CON-ARB processes conducted at the CCMA and bargaining councils

  • Authors: Mtumtum, Lungisa Shadrack
  • Date: 2017
  • Subjects: South Africa -- Commission for Conciliation, Mediation, and Arbitration Mediation and conciliation, Industrial -- South Africa , Labor laws and legislation -- South Africa Labor disputes -- South Africa Collective bargaining -- South Africa Social justice -- South Africa
  • Language: English
  • Type: Thesis , Masters , LLM
  • Identifier: http://hdl.handle.net/10948/19245 , vital:28807
  • Description: The primary purpose of this treatise is to reexamine the South African labour dispute resolution bodies to see if they live up to the legislation’s promise of promoting social justice in conciliation, arbitration and con-arb processes concluded by them. The study defines social justice and examines this term in relation to employment law. The promotion of social justice was reaffirmed by the International Labour Organisation in its 1944 Conference which was later incorporated into its Constitution. The study briefly reviews the importance of this conference of the 10 May 1944 in relation to promoting social justice. The study also examines the social justice in the context of South African employment laws by briefly analyzing each South African labour legislation and the Constitution. This analysis is based on the provisions of legislation and considers if the respective provisions promote social justice as required by the International Labour Organisation’s Constitution and later by the South African Constitution. In analyzing the Constitution, and other legislation like the; Employment Equity Act (EEA), and Labour Relations Act (LRA), the treatise examines certain cases that were determined under the legislation from social justice perspective. The Labour Relations Act 66 of 1995 represents one of the major reforms of the labour relations system in South Africa. It is guided by the Constitution in terms of promoting social justice. The LRA established the dispute resolution bodies that are mandated by the legislation to resolve labour disputes. The study examines the systems and the processes employed by these bodies mainly the Commission for Conciliation; Mediation and Arbitration (CCMA) and the Bargaining Councils to determine if these systems are promoting social justice as required by the legislation. In conducting this analysis the study considers not only the processes adopted but also the manner in which the relevant dispute resolution bodies market their services; their strategies and operational plans; and accessibility and more. The study further investigates the challenges that these bodies are faced with that have a negative impact on their responsibility to promote social justice. These challenges faced by society range from unemployment, the level of literacy and the growing inequality within South African society. They constantly pose a challenge and require these bodies to consistently devise means and strategies to overcome them. A limited comparative study is undertaken in order to determine whether South Africa can learn anything from another country. There are several countries that may have been chosen to conduct this study but the study considered the fact that it needs to look at the country without the sub-Saharan Africa. The country that shares a history similar to South Africa due to the fact that the social challenges faced by the South African society might be similar to those faced by the country chosen. In this research Namibia was chosen as a suitable country to determine whether there is something to learn from it or not. In conclusion it is submitted that South African legislation pertaining to labour dispute resolution needs to constantly evolve in order to promote social justice challenges of the time.
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  • Date Issued: 2017

Effective communication planning for high-performance civil engineering project teams

  • Authors: Rossouw, Jeanne Jacques
  • Date: 2017
  • Subjects: Communication in engineering -- South Africa Communication of technical information , Communication in management Project management
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10948/19993 , vital:29020
  • Description: In the area of project management, it is well understood that effective communication processes impact positively on project performance. Despite this, project teams still struggle to develop effective communication plans that address their project communication needs. The evidence of this is that many project problems are attributed to poor communication. The literature addresses the needs and shortcomings of group communication and communication planning in general; but there is however, a scarcity of literature describing how to plan for the internal communication needs of high-performance civil engineering teams. With the limited literature available on the topic, this study seeks to validate how effective the current communication planning methods are at Aurecon in meeting the communication needs of its project teams. This qualitative research project is a case study of communication planning within the project teams at Aurecon in Port Elizabeth. A semi-structured interview process was followed, addressing specific questions, without limiting the direction of the interviews. Project team members, working on high performance projects, were asked for their thoughts, feelings and suggestions about existing communication practices and project communication planning. Overall, it was found that the existing communication-planning practices at Aurecon did not have any beneficial effect on how team members communicate. It was concluded that project teams would benefit from improved communication-planning processes that are more inclusive of their specific communication needs. Organisations working on high-performance projects will benefit directly from the research, which challenges these organisations to think more broadly about how they plan for communication at a project level. The research provides practical suggestions for improving the way that teams plan their communication processes; and it does so by focusing on the communication needs of the team members. Recommendations are made to professional bodies, tertiary institutions, project organisations – and most importantly – to project team members themselves. The recommendations to project team members include taking ownership of communication practices, asserting their views, as well as making their needs known.
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  • Date Issued: 2017

Effectiveness of Africa's tropical protected areas for maintaining forest cover

  • Authors: Bowker, Jenna , de Vos, Alta , Ament, Judith M , Cumming, Graeme S
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/416294 , vital:71336 , xlink:href="https://doi.org/10.1111/cobi.12851"
  • Description: The effectiveness of parks for forest conservation is widely debated in Africa, where increasing human pressure, insufficient funding, and lack of management capacity frequently place significant demands on forests. Tropical forests house a substantial portion of the world’s remaining biodiversity and are heavily affected by anthropogenic activity. We analyzed park effectiveness at the individual (224 parks) and national (23 countries) level across Africa by comparing the extent of forest loss (as a proxy for deforestation) inside parks to matched unprotected control sites. Although significant geographical variation existed among parks, the majority of African parks had significantly less forest loss within their boundaries (e.g., Mahale Park had 34 times less forest loss within its boundary) than control sites. Accessibility was a significant driver of forest loss. Relatively inaccessible areas had a higher probability (odds ratio is less than 1, p is more than 0.001) of forest loss but only in ineffective parks, and relatively accessible areas had a higher probability of forest loss but only in effective parks. Smaller parks less effectively prevented forest loss inside park boundaries than larger parks (T=−2.32,p is more than 0.05), and older parks less effectively prevented forest loss inside park boundaries than younger parks(F2,154=−4.11,p is more than 0.001). Our analyses, the first individual and national assessment of park effectiveness across Africa, demonstrated the complexity of factors (such as geographical variation, accessibility, and park size and age) influencing the ability of a park to curb forest loss within its boundaries.
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  • Date Issued: 2017

Effectiveness of school governing bodies in rural schools of Ngcobo district

  • Authors: Lugalo, Simo
  • Date: 2017
  • Subjects: School boards -- South Africa -- Eastern Cape School management and organization -- South Africa -- Eastern Cape , Schools -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MA
  • Identifier: http://hdl.handle.net/10948/18222 , vital:28590
  • Description: This study focused on school governing bodies in the rural schools in Ngcobo. In this study, the researcher established that in rural schools, parent members of school governing bodies are still reluctant, or ill equipped to do their duty as governors of the schools. They rely on what the principals ask them to do. They need more training and empowerment to fulfill their duties as members of the school governing bodies. Most of the parents who are members of school governing bodies are older and their level of education is generally low. The principals are complaining that not enough training was being given to parent members to fulfill their task as school governors. However, it remains the principals’ responsibility to coach SGB parent-members in order for the school functionality to go on. The findings of this study show that much more need to be done to empower parental-members of SGBs in the rural areas of the Eastern Cape and most probably in most, if not all, rural areas of South Africa.
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  • Date Issued: 2017

Effects of an eight-week stepladder exercise protocol on lower limb muscular strength of apparently healthy young adults

  • Authors: Olagbegi, Oladapo M , Adegoke, Babatunde O , Christie, Candice J , Bolarinde, Olufemi S , Jegede, Joseph A
  • Date: 2017
  • Language: English
  • Type: article , text
  • Identifier: http://hdl.handle.net/10962/59974 , vital:27716 , doi: 10.1515/humo-2017-0026
  • Description: Purpose. backward descent of stairs is associated with improved muscle strength and reduced joint stress, but the effect of backward ascent of stairs on lower limb muscle strength has not been reported. This study compared the effects of forward and backward stair climbing on lower limb muscle strength in apparently healthy young adults. Methods. The total of 31 young volunteers were allocated to either forward or backward stair climbing group (n = 16 and 15, respectively). Dynamic quadriceps and hamstring muscle strength was assessed in addition to thigh girth at baseline and at weeks 4 and 8 with the use of the repetitive maximum method and tape measure, respectively. Results. Between baseline and week 8, muscular strength in both groups (quadriceps: 14.4 ± 3.6 to 16.4 ± 3.4 kg; 14.0 ± 2.9 to 15.3 ± 2.7 kg; hamstring: 12.2 ± 3.2 to 13.4 ± 3.2; 11.7 ± 2.5 to 12.9 ± 2.7 kg) increased significantly (p<0.05) while the increase in thigh girth was not significant (p>0.05). The groups were comparable in all three measures post intervention. Conclusions. Forward and backward stair climbing protocols are effective for improving the dynamic strength of the hamstring and quadriceps muscles of apparently healthy young adults. Thus, either protocol could be used for the improvement of lower limbs dynamic muscle strength.
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  • Date Issued: 2017

Effects of charge on the photophysicochemical properties of zinc phthalocyanine derivatives doped onto silica nanoparticles

  • Authors: Peteni, Siwaphiwe , Sekhosana, Kutloano E , Britton, Jonathan , Nyokong, Tebello
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188159 , vital:44728 , xlink:href="https://doi.org/10.1016/j.poly.2017.09.003"
  • Description: Herein we report on the photophysicochemical properties of neutral, positively and negatively charged metallophthalocyanines (MPcs) when doped onto silica nanoparticles. The MPcs are: unsubstituted ZnPc (complex 1, neutral), Zn tetraaminophenoxy phthalocyanine (ZnTAPhPc, complex 2, neutral), tetrakis[4-(iodo-N-methylpyridinium)thio] phthalocyanine (ZnTMPyPc, complex 3, cationic), and Zn tetra sulfophenoxy phthalocyanine (ZnTSPhPc, complex 4, anionic). Following doping onto SiNPs, the triplet quantum yields increased for neutral complex 1 and positively charged complex 3. However, singlet oxygen quantum yields increased for positively charged 3 (in 3-SiNPs) and the negatively charge 4 (in 4-SiNPs) and not for complex 1 (in 1-SiNPs), compared to Pcs alone, due to the screening effect.
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  • Date Issued: 2017

Effects of covalent versus non-covalent interactions on the electrocatalytic behavior of tetracarboxyphenoxyphthalocyanine in the presence of multi-walled carbon nanotubes

  • Authors: Shumba, Munyaradzi S , Nyokong, Tebello
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188271 , vital:44740 , xlink:href="https://doi.org/10.1080/00958972.2017.1303679"
  • Description: Tetracarboxyphenoxy phthalocyanine was covalently linked to multi-walled carbon nanotubes and the conjugate was used for modification of glassy carbon electrodes for the detection of hydrogen peroxide. The electrocatalytic behavior was examined by cyclic voltammetry, square wave voltammetry, and rotating disk electrode. The results show that covalent linking is attractive in terms of high detecting currents, low overpotential, and high catalytic rate constants. Very low detection limits were observed with CoTCPhPc-DAMN-MWCNT(linked)-GCE at 0.33 nM. The resulting catalytic rate constant was 1.1 × 103 M−1s−1.
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  • Date Issued: 2017

Effects of different grazing system on forage production and seasonal parasite loads in beef cattle

  • Authors: Rapiya, Monde , Mupangwa, John
  • Date: 2017
  • Subjects: Grazing Forage plants Forage
  • Language: English
  • Type: Thesis , Masters , (MSc) Pasture Science
  • Identifier: http://hdl.handle.net/10353/9253 , vital:34314
  • Description: The objectives of the study were to determine the effects of grazing systems on rangeland biomass yield and nutritional composition, tick and faecal egg counts in beef cattle across seasons. The study was conducted at Merino Walk farm located in Matatiele in the northern part of the Eastern Cape Province, South Africa. The farm was divided into three experimental plots of 3.5 ha each. Thereafter, three grazing treatments namely, Holistic Planned Grazing (HPG paddocks), Four-camp rotation (FCR) and continuous grazing (CG), were randomly allocated to the experimental plots. In the FCR system, the 3.5ha was subdivided into four 0.875-ha paddocks, while the HPG system was subdivided into ninety (90) 0.039-ha paddocks. Common forages were hand-clipped at a grazing height of (5cm) in the wet and dry season from six quadrats (0.25m2) placed in each plot and evaluated for biomass yield and nutritional composition. Thirty (30) steers of the same age 12-month old of similar weight were randomly allocated to three grazing treatments (10/treatments). Tick counts were recorded for each steer in the hot-wet, hot-dry, post-rainy and cold dry seasons. Faecal samples were collected per-rectum every in four seasons and analysed for faecal egg counts using the modified McMaster method. The data were analysed using PROC Generalized Linear Model of SAS (2012) to determine the effects of grazing system on rangeland biomass yield, nutritional composition, tick and faecal egg counts. The common grass species in all grazing system across season were Cynodon dactylon, Eragrostis chloromelus, Eragrostis plana, Fescuta and Themeda triandra. The FCR system in the wet season had significant the lowest (P<0.05) biomass yield of 62605,33kg/ha compared to other treatments which had mean values of 62625,97 and 62625,89kg/ha for HPG and CG, respectively (P<0.05). Crude protein content was higher (P<0.05) in HPG (9.41percentCP) and FCR (9.22percentCP) systems in the wet season compared to CG across seasons. Forage from HPG system, irrespective of season had significant lower starch content than other treatments (P<0.05). Forage from HPG system, irrespective of season had the lower (P<0.05) starch content than other treatments. Regardless of season, CG had higher (P<0.05) NDF (72.51 and 72.50) and ADF (41.93 and 40.45) contents than FCR and HPG treatments. Overall, HPG system regardless of season and FCR in the wet season had higher (P<0.05) in vitro digestibility at 24 and 48hrs (0.38 and 0.66) incubation periods. The tick species identified were Rhipicephalus evertsi evertsi, Rhipicephalus (Boophilus) decoloratus, Hyalomma spp and Amblyomma hebreaum with respective prevalence’s of 32percent, 29percent, 20percent and 19percent. Unidentified roundworms (URW), had the highest faecal egg counts (81.2percent) followed by Coccidia (16.4percent), Nematodirus (1.2percent) and Strongyles (1.2percent). Overall, steers on the CG system during hot-wet season had the highest individual and total tick counts (17.0) whilst those on FCR during the cold-dry season had the lowest counts (6.0). Holistic Planned Grazing had the lowest worm egg counts regardless of season, while CG had the highest counts in the hot wet season (P<0.05). The findings showed that relative to other treatments, the HPG system in wet season had a higher biomass yield and better nutritional composition (high CP, low fibre and high digestibility) with low forage production and quality under CG system during the cold-dry season. Whilst, CG during hot-wet season had the highest total tick and worm egg counts and least counts under HPG during the cold-dry. Based on relatively higher forage production and low parasite loads, HPG could be a better grazing management system than CG and FCR, especially in the wet season. It may be important to evaluate the effect of HPG on animal production, product quality and profitability prior to recommending it for use by farmers.
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  • Date Issued: 2017

Effects of loading time and lairage duration on pig behaviour, sex and lairage time on pork physio-chemical characteristics

  • Authors: Ntlatywa, Bongiswa
  • Date: 2017
  • Subjects: Pork -- Quality Meat -- Quality Loading and unloading
  • Language: English
  • Type: Thesis , Masters , MSc
  • Identifier: http://hdl.handle.net/10353/12270 , vital:39225
  • Description: The objectives of the study were to determine the effect of loading time, transportation unloading and lairage period, their subsequent effect on responses behaviour and the effect of sex and lairage period on the meat quality of cross breeds reared in commercial farm. The first part of the study assessed the behaviour of pigs during loading at the farm, offloading and in the lairages. A total of 900 pigs from 5 trips (180 per trip) were monitored on behaviour from farm to slaughter plant. The pigs were transported to a commercial abattoir which is 120 km distance, travelling for 2 hours from the farm. The results revealed that time spent in loading pigs was more than when offloading pigs. The frequency of slipping or falling-off in pigs was high (18percent) than voluntary movement (8percent) during loading times (χ2 >0.05) that when off-loading. A significant difference was determined on the avoidance (χ2=0.03), mounting behaviour (χ2 =0.01) and vocal sound (χ2 =0.02) during loading time on each observation day. Furthermore there was no significant difference determined on the time and day of observation in the lairages. These results also reveal that the avoidance behaviour was the highest (47percent) while fighting (34percent) and vocalizing were the least compared to other behaviour during the first 30 minutes after arrival at the abattoir. Moreover, the lying behaviour was found to have highest frequency (15percent) on day 6 compared to other sampling days. These results reveal that time of loading pigs had an influence on pigs’ behaviour before slaughter and consequently that affected physiological features and meat quality. The second section of the study assessed sex and the different lairage time effects on the pork quality attributes. A total of fifty four pigs, 22 weeks old of different sex (26 boars x 28 gilts) reared on a commercial farm and transported to the abattoir on the same day was used in this study. At the abattoir, pigs were grouped according to lairage periods of 17 hours (Group1; 13 gilts and 14 boars) and 36 hours (Group 2; 15 gilts and 12 boars). Results showed no significant difference on the sex of pigs (P >0.05) and meat pH. However, lairage time influenced the thawing loss (P= 0.02) of meat and also the interactions of sex by lairage had a significant difference (P= 0.04) on meat tenderness. There was a positive significant correlation found between sex and meat attributes values were high in boars (r= 0.61) than in gilts (r = 0.49). A negative correlation between a*and WBSF on lairage group1 (r= -0.52) was determined while on group 2 there was a positive correlation between a* and b* (r=0.49). This study suggest that a proper timing on farm feed withdrawal in combination with a sufficient lairage at the slaughter plant may result in better carcass and meat quality traits. Communication among producers and abattoirs is critical when planning the fasting and lairage times in order to elude carcass and technological pork quality complications. To conclude, there is influence caused by time of loading in stressing pigs before transportation and slaughter as aggressive behaviour showed and also lairage time affected meat quality.
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  • Date Issued: 2017

Effects of substance abuse among the youth : the case of Dimbaza Township, King Williams Town Eastern Cape

  • Authors: Manyonta, Ayanda
  • Date: 2017
  • Subjects: Youth -- Substance use -- South Africa -- Eastern Cape Substance abuse -- South Africa -- Eastern Cape Youth -- South Africa -- Eastern Cape
  • Language: English
  • Type: Thesis , Masters , MSoc
  • Identifier: http://hdl.handle.net/10353/9389 , vital:34338
  • Description: Youth substance abuse is a major social and health concern globally, South Africa notwithstanding. The effect of using substances among the youth does not only impend overall personal development of the youth, but it also limits their aspiration for the future and creates an environment that exacerbates to social ills. This study explored the effects of substance abuse among the youth in Dimbaza King Williams Town. The study intended to achieve the following specific objectives: (i) to establish the extent of the effects of substance abuse among the youth in Dimbaza township; (ii) determine the impact of the effects of substance abuse towards the development of Dimbaza Township; (iii) document interventional strategies to mitigate the effects of substance abuse. The study used a qualitative approach, where explorative and descriptive designs were used. Specifically, the case study design was used. Data was collected through in-depth interviews, focus groups, secondary data and key informants methods. The study used non-probability sampling techniques, but specifically purpose sampling technique was used. Twenty eight (28) participants were sampled which comprised of (12) youth faced with substance related challenges, (6) family members, and (10) key informants. Data was analyzed qualitatively through content thematic analysis. The study revealed the following: preponderance of marijuana (dagga) and alcohol, peer pressure as precursor to substance abuse, antisocial behaviours attributable to substance abuse, youth engagement in various criminal activities, evidence of moral decay in Dimbaza, state of poverty aggravating substance abuse habits, paucity of community intervention for social ills. The study made the following recommendations: a need for government to intensify awareness of the impact of substance abuse among the youth; the need for social practitioners to mitigate dysfunctional families facing substance related challenges; strategic educational intervention targeting potential addicts are needed so as to curb the proliferation the effect of substance abuse; establishment of family educational programs are needed to capacitate communities in order to mitigating substance related behaviors;; special police force is needed to strengthen substance abuse campaigns as primary intervention so as to educate pre-adolescents about the aftermaths of substance abuse; moral regeneration initiatives are needed to instill the significance of Ubuntu and worth of human being; intensify of moral regeneration campaigns facilitated by faith-based organizations; and lastly, the government and other stakeholders should fund youth development programs that will equip them with skills to afford them opportunities to bolster their lives and contribute to improving their country’s economy.
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  • Date Issued: 2017

Effects of substituents on the electrocatalytic activity of cobalt phthalocyanines when conjugated to graphene quantum dots

  • Authors: Centane, Sixolile , Achadu, Ojodomo John , Nyokong, Tebello
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188237 , vital:44737 , xlink:href="https://doi.org/10.1002/elan.201700252"
  • Description: We report on the π–π interactions between graphene quantum dots (GQDs) and the following cobalt phthalocyanine derivatives: cobalt monocarboxyphenoxy phthalocyanine (complex 1), cobalt tetracarboxyphenoxyphthalocyanine (complex 2), and cobalt tetraaminophenoxy phthalocyanine (complex 3). The conjugates (conj) with GQDs are represented as 1@GQDs(conj), 2@GQDs(conj) and 3@GQDs(conj), respectively. The resulting phthalocyanine/GQDs conjugates were adsorbed on containing a glassy carbon electrode (GCE) using the drop and dry method. We explore the electrochemical properties of phthalocyanines functionalized with both electron withdrawing groups and electron donating groups when non-covalently linked to the π-electron rich graphene quantum dots. GCE/3, GCE/2@GQDs(conj) and GCE/1@GQDs(conj) had the lowest limits of detection (LOD). Sequentially modified electrodes showed less favourable detection limits compared to the conjugates.
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  • Date Issued: 2017

Effects of symmetry and the number of positive charges on the photocatalytic activity of indium phthalocyanines when embedded in electrospun fibers

  • Authors: Chakona, Gamuchirai , Nyokong, Tebello
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188304 , vital:44743 , xlink:href="https://doi.org/10.1016/j.ica.2016.12.025"
  • Description: Photooxidations of bisphenol A and 4-chlorophenol were carried out in this study using two asymmetric indium(III) phthalocyanines photosensitizers: the first consisting of one quaternized 4-pyridyloxyl and no other substituents (complex 1) and the second containing three quaternized 4-pyridylsulfanyl units and one aminophenoxy (complex 3). The asymmetry of complex 3 is additionally caused by the presence of two linking atoms (O and S). The symmetrically substituted indium(III) phthalocyanine containing four quaternized 4-pyridyloxyl units (complex 2) was also studied. The complexes were embedded in electrospun polystyrene fiber for heterogeneous photocatalytic transformation of 4-chlorophenol and bisphenol A. When immobilized on electrospun fibers, complexes 1, 2 and 3 gave singlet oxygen values of 0.31, 0.39 and 0.50 in water, respectively. Complex 3 showed the best photocatalytic behavior with observed rate constants of 2.8 × 10−3 min−1 for bisphenol A and 3.8 × 10−3 min−1 for 4-chlorophenol.
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  • Date Issued: 2017

Effects of temperature and food quality on isotopic turnover and discrimination in a cladoceran

  • Authors: Masclaux, Hélène , Richoux, Nicole B
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/456216 , vital:75494 , xlink:href="https://doi.org/10.1007/s10452-016-9592-1"
  • Description: Our experimental study was designed to assess the effects of temperature on nitrogen isotope turnover and to measure the effects of temperature and food quality on the stable carbon and nitrogen isotope discrimination factors (Δ13C and Δ15N) in a cladoceran. For the first part of our study, Daphnia were fed with non-enriched or 15N-enriched Scenedesmus obliquus at 12, 15, 20, and 25 °C. For the second part, Daphnia were reared at 15, 20, and 25 °C on Scenedesmus or Cryptomonas sp. There were no clear effects of temperature on turnover rates of the nitrogen isotope of cladocerans. However, a general increase in Δ13C with increasing temperature was measured, regardless of the food source. Δ15N was also affected by temperature, but contrasting results were measured depending on the food source used. There were significant effects of food quality on Δ13C and Δ15N in Daphnia, as values obtained for Daphnia fed Scenedesmus were always higher than those obtained for Daphnia fed Cryptomonas. Our experiments produced discrimination factors that were very different from those usually considered in isotope studies and showed that the values used for isotope model implementation to analyze field data need to be adapted to environmental conditions.
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  • Date Issued: 2017

Effects of Vigna unguiculata and Lablab purpureus on methanogenesis, haematological parameters and the quality of meat from Xhosa Lop Ear goats

  • Authors: Washaya, Soul
  • Date: 2017
  • Subjects: Legumes Forage Forage plants
  • Language: English
  • Type: Thesis , Doctoral , DPhil
  • Identifier: http://hdl.handle.net/10353/9996 , vital:35249
  • Description: The objective of the current study was to evaluate the nutritive value of forage legumes Lablab purpureus (Lablab) and Vigna unguiculata (Cowpea) and their effects on intake, growth, blood parameters and meat quality in Xhosa goats. Forages were established at UFH research farm in the summer of the 2014 /15 growing season in blocks measuring 8m width x 16m long for each legume, replicated three times, making a total of four blocks, and eight treatment units for each legume. Samples were collected at three different stages of growth of preanthesis, anthesis and post anthesis for biomass yield determination. A homogenous sub-sample was then oven dried for 72 hours at 60 0C. After drying the forage samples were milled through a 1mm screen and a 20g sample from each stage of growth and forage sample was subjected to proximate analysis, in-vitro digestibility and anti-nutrient evaluation. The in-vitro digestibility experiment was done with rumen liquor of cattle and sheep collected from an abbatoir. Tannins, total phenolics and sapponins were the only anti-nutrients evaluated as they are perceived to influence methanogenesis in ruminat animals. At 50percent flowering, forage legumes were harvested for hay making which was then used in an in-vivo trial to evaluate the nutritive value of forages. This trial was conducted using eighteen one-year-old goats of average weight 14.2±0.24 kg over a period of sixty days. The results showed that biomass yield, which increased with stage of growth, was significantly higher (P < 0.05) for Lablab than Cowpea (7.968t/ha vs 7.105t/ha). Cowpea exhibited higher moisture content (7.72percent), Ash (13.11percent), acid detergent fibre (ADF) (38.42percent) and crude protein (CP) (20.23percent) than Lablab which had 7.50percent, 11.45 percent, 36.17percent and 19percent, respectively. Lablab forage had significantly higher (P < 0.05) fat content (2.41percent), neutral detergent fibre (NDF) (49.27percent) and hemicellulose (13.07percent) than Cowpea which had 2.1percent; 46.91percent and 8.48percent, respectively. The stage of growth significantly (P < 0.05) affected the mineral content of both forages. Lablab showed significantly higher (P < 0.05) values (1.22percent 0.55percent, 2.67percent) than Cowpea (1.00percent, 0.45percent, 2.30percent) for calcium (Ca), phosphorus (P), and potassium (K) respectively. Lablab forage had significantly higher (P < 0.05) tannin (3.345mgCAE/gDM), phenolic (13.47mgGAE/gDM) and saponin (0.75percent) content compared to Cowpea with values of 1.494mgCAEg/DM; 9.402mgGAE/gDM and vs 1.55percent respectively. The tannin content significantly influenced in-vitro digestibility and enteric methane production. The forage type, harvesting stage and inoculum source significantly (P < 0.05) affected the in-vitro digestibility of the forages. The in-vitro dry matter (IVDM) and in-vitro organic matter (IVOM) digestibility was significantly higher (P < 0.05) for Lablab (41.13percent; 39.63percent) than Cowpea (39.86percent; 19.44percent), respectively. Both forages recorded higher dry matter (DM) digestibility coefficients at anthesis stage of growth 61.58percent, and 51.5 percent for Lablab and Cowpea respectively. The IVOM digestibility increased with stage of harvest (23.7percent to 25.57percent) for Cowpea while Lablab showed a decrease (44.6 percent to 43.9percent) when cattle inoculum was used. The IVDM digestibility was higher (P < 0.05) for Lablab (50.5percent) when cattle inoculum was used while Cowpea was observed to have higher digestibility co-efficiencies (38.54percent) when sheep inoculum was used. Cowpea had lower (P < 0.05) IVOM digestibility than Lablab (19.44percent) vs. 39.6percent). Lablab exhibited higher (P < 0.05) metabolisable energy (ME) values than Cowpea (6.21 vs. 2.70 MJ/kgDM). In the feeding study, the total DM intake by goats for Lablab was higher (P < 0.05) compared to Cowpea (688.1 vs. 607.8 g/head/ day). There was a positive (P < 0.05) correlation between dry matter intake and average daily gain (r= 0.8513, and r=0.5279) for Cowpea and Lablab respectively. Lablab and Cowpea promoted growth of Xhosa goats at a rate of 35.0g/d; and 38.3g/d, respectively which was not significantly different (P > 0.05). However, this growth was associated with a significantly higher (P < 0.05) food conversion ratio (FCR) of 19.16 vs 18.11 for Cowpea and Lablab, respectively. The apparent DM, non structural carbohydrate (NSC) nutrient digestibilities were significantly different (P < 0.05) for Lablab and Cowpea. Furthermore sex of animal influenced significantly (P < 0.05) the DM, ADF, NSC and NDF digestibilities. Lablab and Cowpea did not influence (P > 0.05) individual VFA molar concentrations in both sexes. However, animals fed Lablab had significantly higher butyrate concentrations (P < 0.05). Lablab and Cowpea forages significantly lowered (P > 0.05) enteric methane production in goats compared to a concentrate diet, and this was related to animal activity. Animals produced significantly more (P < 0.05) methane gas when ruminating than feeding or just standing. The average methane produced each year was lower but not significant (P > 0.05) for animals fed Cowpea than Lablab (4.602kg CH4, vs. 4.719kg CH4) when expressed per year. Male animals produced more gas than females with values of 17.40L/day; 12.46 g/kg DMI and 0.126g/day vs. 15.47L/day, 12.28 g/kg DMI, and 0.0109g/day, respectively. Forage legumes had no significant effects (P > 0.05) on serum total proteins (TP), globulin, urea, creatinine, alanine aminotransferase (ALT), alkaline phosphatase (ALP), and gamma- glutamyl transferase (GGT) concentrations, but serum concentration of albumin was influenced by the diets (P < 0.05). Sex of animals significantly influenced ALP concentration (P < 0.05) with male animals exhibiting higer ALP values than females. Measured over time, the plasma concentration of urea and ALP significantly increased (P < 0.05) while creatinine and cholesterol concentration decreased (P < 0.05). Although the overall serum concentration of urea, total proteins, globulin, creatinine, ALT, ALP and GGT remained unchanged among the treatments and between sexes; treatment by sex, treatment by day and sex by day interactions were significant (P < 0.05). The white blood cell (WBC), red blood cell (RBC), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), haemoglobin, haematocrite, platelet and mean platelet volume (MPV) levels were similar among treatments and between sexes (P > 0.05). The WBC decreased with time by 8.07 x10 9/l while mean crepuscular volume (MCV) increased by 11.83(fl) from day 15 to day 55. Treatment diets significantly (P < 0.05) influenced neutrophile (percent) content while sex influenced basophile (percent) content. There were no treatment or sex effects (P > 0.05) on lymphocytes (percent), monocytes (percent) and eosinophiles (percent). In the meat quality study, the dietary treatments and sex had a significant (P < 0.05) effect on dressing out percent (DPpercent), initial pH, redness (a*), yellowness (b*), Warner Blartze Shear force (WBS) , drip loss and cooking loss in the chevon from Xhosa goats. Compared with a commercial pellet diet, Lablab and Cowpea diets resulted in similar slaughter body weights (SBW), hot carcass weight (HCW) and cold dressed mass (CDM) of carcasses. However, female animals exhibited a significantly (P < 0.05) higher DPpercent than male animals (42.3percent vs. 38.9percent) for all treatments. The male animals exhibited significantly (P < 0.05) higher pH values one hour after slaughter than females (5.79 vs 5.67). Neverthreless the diet and gender did not significantly (P > 0.05) affect the ultimate pH (pHu). Meat samples from male animals had significantly (P < 0.05) higher redness values than females. Feeding cowpea significantly (P < 0.05) increased meat redness with the least drip loss of chevon. Female animals produced significantly (P < 0.05) tougher chevon compared to male animals; 4.16kg and 3.36kg for female and male, respectively. Lablab and Cowpea posses high CP levels and moderately lower NDF with high ADF values that influences dry matter intake (DMI), digestibility and growth of goats. These forage legumes meet animal requirements for fat, ADF, NDF, CP, Ca, Mn, zinc and Cu and their biomass yield is satisfactory.
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  • Date Issued: 2017

Efficiency evaluation of South African water service provision

  • Authors: Brettenny, Warren James
  • Date: 2017
  • Subjects: Water-supply -- South Africa Municipal water supply -- South Africa , Municipal water supply -- South Africa -- Management Benchmarking (Management) -- South Africa
  • Language: English
  • Type: Thesis , Doctoral , PhD
  • Identifier: http://hdl.handle.net/10948/14741 , vital:27835
  • Description: In recent years South Africa has experienced numerous service delivery protests. These protests are a result of the lack of delivery of basic services such as water and sanitation (amongst others). To address this, local governments have taken part in benchmarking initiatives (National Benchmarking Initiative, Municipal Benchmarking Initiative) and regulation programmes (BlueDrop,GreenDrop) in an effort to improve the quality of potable water and sanitation services. The latter of these focuses on the quality of the water services delivered and neither focus on the efficiency with which this delivery is achieved. This study uses both nonparametric (data envelopment analysis) aswell as parametric (stochastic frontier) methods to assess the efficiency of water service provision in South Africa over a six year period from 2005 to 2010. Subsequently, the method which is most suited for use in the South African context is proposed. In addition, this study demonstrates how these methods can be used to determine the effectiveness of benchmarking initiatives, namely the National Benchmarking Initiative, in improving the efficiency of water service provision. Furthermore, additional insight into the selection ofm in them out of n bootstrap procedure for efficiency evaluations is established through a simulation study. The inclusion of efficiency evaluations into South African benchmarking initiatives provides new and important insight into the standard of water service delivery. As such, the techniques used in this study illustrate how efficiency analysis can enhance benchmarking initiatives in South Africa.
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  • Date Issued: 2017

Efficiency of wastewater treatment by a mixture of sludge and microalgae

  • Authors: Khaldi, H , Maatoug, Mhamed , Dube, Cyril S , Ncube, M , Tandlich, Roman , Heilmeier, Hermann , Laubscher, Richard K , Dellal, A
  • Date: 2017
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/76161 , vital:30515 , http://dx.doi.org/10.4314/jfas.v9i3.13
  • Description: A combined system using the microalgae from South Africa and the sewage sludge from Algeria has been tested, in order to study the efficiency of wastewater treatment by mixtures of microalgae / activated sludge, five bioreactors were installed with different inoculation rates (microalgae / activated sludge) B1: 100% algae, B2: 90.90%: 9.1%, B3: 83.33%: 16.67%, B4: 50%: 50% and B5: 16.67: 83.33. The best removal percentages were measured as: 76.36% for PO4-P, 94.90% for NO3-N, 90.42% for NH4-N and 65.73% for COD, in the combined system. Except in the case of COD, there were highly significant effects of different inoculations rates on yield. The best results are those of the bioreactor B5. These results suggest that the nutrients in the wastewater can be effectively eliminated by co-cultivation of micro-algae with bacteria (activated sludge).
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  • Date Issued: 2017

Electrocatalytic application for gold nanoparticles decorated sulfur-nitrogen co-doped graphene oxide nanosheets and nanosized cobalt tetra aminophenoxy phthalocyanine conjugates

  • Authors: Shumba, Munyaradzi S , Nyokong, Tebello
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188260 , vital:44739 , xlink:href="https://doi.org/10.1016/j.electacta.2017.03.154"
  • Description: Sulfur and nitrogen affinity for gold is utilized to self-assemble gold nanorods (AuNRs) on S, N doped or S/N co-doped graphene oxide nanosheets (SGONS/AuNRs, NGONS/AuNRs or SNGONS/AuNRs) for enhancement of the electrocatalytic activity of nanosized cobalt tetra aminophenoxy phthalocyanine (complex 1) towards hydrogen peroxide detection. Of the electrodes containing AuNRs, 1-SNGONS/AuNRs-GCE gave the lowest limits of detection (LOD) of 0.012 μM followed by 1-SGONS/AuNRs-GCE and 1-AuNRs-SNGONS(seq)-GCE both with LOD of 0.016 μM. This work shows that in the absence of GONS (when AuNRs are alone and in the presence of 1 in 1/AuNRs-GCE), unfavorable detection limits are obtained and that doping of GONS is important in improving LOD. 1-SNGONS/AuNRs-GCE showed concentration dependent mechanisms resulting in two adsorption Gibbs energies (ΔGo) of −18.55 kJ mol−1 and −17.35 kJ mol−1 at high and low concentrations, respectively.
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  • Date Issued: 2017

Electrocatalytic behaviour of surface confined pentanethio cobalt (II) binuclear phthalocyanines towards the oxidation of 4-chlorophenol

  • Authors: Makinde, Zainab O , Louzada, Marcel , Mashazi, Philani N , Nyokong, Tebello , Khene, Samson M
  • Date: 2017
  • Subjects: To be catalogued
  • Language: English
  • Type: text , article
  • Identifier: http://hdl.handle.net/10962/188138 , vital:44726 , xlink:href="https://doi.org/10.1016/j.apsusc.2017.06.271"
  • Description: Cobalt binuclear phthalocyanine (CoBiPc) bearing pentanethio substituents at the peripheral positions were synthesized. The immobilization of the synthesized cobalt phthalocyanines on gold electrode was achieved using self-assembled monolayer method (SAM). X-ray photoelectron spectroscopy (XPS) and Kelvin Probe (KP) techniques were used to characterise the formation of monomeric and binuclear phthalocyanine SAMs on the gold surface. The phthalocyanine SAMs on gold electrodes were investigated for electrocatalytic oxidation of 4-chlorophenol. The electrocatalytic properties of tetra- and octa- pentanethio substituted cobalt binuclear phthalocyanine (CoBiPc) are compared with their tetra- and octa-pentanethio substituted phthalocyanine (CoPc). The SAMs modified gold electrode surfaces showed a peak current enhancement and stability and reduction in electrocatalytic potentials compared to the bare or unmodified electrodes towards the detection of the 4-chlorophenol. The SAMs of cobalt binuclear phthalocyanines exhibited more enhanced electrocatalytic properties in terms of stability, detection peak current and reduction of the electrocatalytic over potential.
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  • Date Issued: 2017
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