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People Parks Win-Win Framework: Integrating components that can influence people-park relationships
No full textProtected areas are often surrounded by impoverished communities. Biodiversity must
be conserved while improving community well-being. Greater insight is required into
what influences pro-conservation attitudes and behaviour in these communities. Much
appears to rest on the relationships between protected area staff and local communities
surrounding the parks, yet there is limited understanding of stakeholders’ perceptions
and how to pragmatically achieve win-win solutions. With the current lack of a
multidimensional framework to enhance understanding of this complex and dynamic
relationships, this research aimed to construct a comprehensive integrated framework
representing the components that can influence people-park relationships. The
framework was constructed via a threefold approach, namely a broader literature review,
a focused study of existing schemata and primary research regarding the attitudes and
behaviour of three local communities bordering three different protected areas in South
Africa. The resultant People Parks Win-Win Framework consists of four layers (each
with its own components): ‘External context’, ‘Stakeholders’, ‘Community beneficiation’
and ‘Outputs’. Its unique arrangement focuses on beneficiation, inclusion of more
stakeholders and their characteristics, the centrality of relationships and demonstration
of outputs (how preceding layers can culminate in win-wins and how pro-conservation
attitudes and behaviour fit into this). A simplified framework is also provided, for
stakeholders to superimpose their own characteristics, benefits, influences and
beneficiation principles. This research draws on the work of others as well as primary
research to produce this multidimensional framework capturing the influences on
people-park relationships with a focus on achieving both community well-being and
biodiversity conservation.
Conservation implications: Win-wins for community well-being and biodiversity
conservation are complex. Yet potential exists for tangible and intangible beneficiation,
which can foster positive attitudes resulting in pro-conservation behaviour and robust
reciprocate relationships between parks and neighbouring communities. To this
end, the framework serves as a practical tool for protected area managers and
stakeholders involved in the people-park relationships, which can be customised to
particular contexts.Transport Economics, Logistics and Touris
Spiritual leadership at the workplace : a comparison of the spiritual leadership models of Louis Fry and Anselm Grün
No full textSummaries in German, English, Zulu and AfrikaansGlaube ist in unserer westeuropäischen Kultur Privatsache. Gleichzeitig ist Spiritualität ein
Megatrend des aktuellen Jahrhunderts, der in der Öffentlichkeit immer mehr Raum
einnimmt. Spiritual Leadership ist dabei ein Ansatzpunkt, um das Spannungsfeld zwischen
Glauben im Privaten und Glauben in der Öffentlichkeit (der Fokus liegt dabei auf der
Arbeit) zu überwinden. Die vorliegende Thesis vergleicht zwei bedeutsame Ansätze des
Spiritual Leadership am Arbeitsplatz. Hierbei handelt es sich zum einen um das explizit als
Spiritual Leadership betitelte Modell von Louis Fry. Mit Frys Modell soll der zweite zu
betrachtende Ansatz des Benediktinerpaters Anselm Grün verglichen werden. Durch
diesen Vergleich stelle ich die Erkenntnisse beider Modelle in den innerdeutschen Diskurs
und zeige anhand dieser Führungsmodelle auf, wie Spiritualität bzw. Glaube am
Arbeitsplatz Auswirkungen hat; abschließend würdige ich die Modelle theologisch.Faith is a private matter in our Western European culture. At the same time, spirituality is
a megatrend of the current century, which is becoming more and more important in
public. However, there is still a desire in the Western culture to make a difference
between faith in the private sphere and faith in the public workplace. Spiritual Leadership
has the potential to overcome this tension. This thesis compares two significant
approaches of spiritual leadership in the workplace. First, Louis Fry's approach will be
discussed, which is explicitly titled Spiritual Leadership. Fry's approach will be compared
with the approach of the Benedictine Father, Anselm Grün. The purpose of this research
is to compare these two models and make their findings available to the German
discourse. Also, this comparison will show how spiritual leadership is impacting the
workplace and, finally, I will discuss both models theologically.Ukholo luyindaba yangasese esikweni lethu laseNtshonalanga Yurophu. Ngesikhathi
esifanayo, ingokomoya liwumnyakazo omkhulu yekhulu leminyaka lamanje, elibaluleke
kakhulu emphakathini. Kodwa-ke, sisekhona isifiso emasikweni aseNtshonalanga
ukwenza umehluko phakathi kokholo emkhakheni wangasese kanye nokholo endaweni
yokusebenza yomphakathi. Ubuholi obungokoMoya bunamandla okunqoba lokhu
kushuba. Le ndaba ende iqhathanisa izindlela ezimbili ezibalulekile zobuholi bomoya
emsebenzini. Okokuqala, kuzoxoxwa ngendlela kaLouis Fry, ebizwa ngokucacile ngokuthi
Ubuholi bongokomoya. Indlela kaFry izoqhathaniswa nendlela kaBaba waseBenedictine,
u-Anselm Grün. Inhloso yalolu cwaningo ukuqhathanisa lezi zifanekiso ezimbili nokwenza
lokho okutholakele kutholakale enkulumeni yesiJalimane. Futhi, lesi siqhathaniso
sizokhombisa ukuthi ubuholi bongokomoya bunomthelela kanjani emsebenzini futhi,
ekugcineni, ngizoxoxa ngezifanekiso zombili ngokwezenkolo.Geloof is ’n private aangeleentheid in ons Wes-Europese kultuur. Terselfdertyd is
spiritualiteit ’n megatendens van die huidige eeu, en ’n saak wat toenemend belangrik
word in die openbaar. Daar is egter steeds ’n behoefte in die Westerse kultuur om
onderskeid te tref tussen geloof in die private sfeer en geloof in die openbare werksplek.
Spirituele leierskap het die potensiaal om hierdie spanning te oorkom. Hierdie tesis
vergelyk twee betekenisvolle benaderings tot spirituele leierskap in die werksplek. Eerste
onder bespreking is Louis Fry se benadering, met die eksplisiete titel Spirituele Leierskap.
Fry se benadering word dan vergelyk met dié van die Benediktynse monnik, Anselm Grün.
Die doel van hierdie navorsing is om hierdie twee modelle te vergelyk en die bevindinge
beskikbaar te stel aan die Duitse diskoers. Hierdie vergelyking sal ook aandui hoe
spirituele leierskap die werksplek affekteer. Laastens sal ek albei modelle teologies
bespreek.M. Th. (Christian Leadership)Philosophy, Practical and Systematic Theolog
Book Review: Eating from One Pot: The Dynamics of Survival in Poor South African Households, by Sarah Mosoetsa
No full textThis is a book review.N/ASociolog
Potato (Solanum tuberosum L.) production in a changing climate: analysis of responses to elevated temperature and moisture conditions
Get PDFSummaries in English, Zulu and TsongaThis study was undertaken to investigate the effects of increasing atmospheric temperature, combined with either drought or flooding, on the growth, development and productivity of the Markies and Fianna potato cultivars. Furthermore, the effects of abiotic stress on the metabolomic profile of these two potato cultivars were studied and a comparison of their quality, growth and yield was drawn. These two potato cultivars (i.e. Markies and Fianna) were planted over three growing seasons. The first experiment (2016) was a preliminary study, undertaken to evaluate the methodology to be used for research on the effects of environmental stresses brought by climatic changes (that is, drought, flooding and increasing temperature) on potato growth and development. During this experimentation year (2016) growth chambers were used to control temperature on three levels: Growth chamber 1 (24°C), Growth chamber 2 (25°C) and Growth chamber 3 (27°C). Due to the size constraint of growth chambers, only 32 plants could be planted. The other two growing seasons (2017 and 2018), each experiment consisted of 108 potatoes planted (total 216 plants) and were exposed to three different water treatments, i.e. normal (control), flooding and drought; administered using portable water in a completely randomised block design in the greenhouse. In total, 98 metabolites were detected through LC-MS from the potato leaves. In addition, representative tubers of the treated plants were collected 91 days after planting. The tuber samples were freeze-dried, and ground to a fine powder in liquid nitrogen. The fine powder of the tuber samples was analysed by nuclear magnetic resonance spectroscopy (NMR) to identify their metabolomic profiles. The NMR data was analysed using principal component analysis and orthogonal partial least square discriminant analysis to identify any variations between the treatments. In both models, plants exposed to drought clearly separated from the plants that received either excess or moderate water. The potato tubers that experienced drought and flood treatments had the highest quantities of aspartic acid, asparagine, and isoleucine.
The treatments resulted in varied quantities of metabolite production in both cultivars. Plants defense metabolites, such as phenylalanine, 2-aminobutyric, amino acids, valine, isoleucine and leucine were increased in the drought and flood experiments, supporting the notion that abiotic stress can result in strong expression of compounds such as these, as a tolerance mechanism. Therefore, influence of increasing temperature and the availability of water was observed on the plant growth and development response of these potatoes. Although the study was carried out in greenhouses during 2017 and 2018, the experimentation years, atmospheric temperature data were obtained from the South African Weather Services (SAWS). The temperature data from SAWS revealed that a 0.75°C temperature increase was recorded in the 2018 experimentation year. As a result, drought treatment in this experiment, combined with increasing temperature, proved to be more detrimental to plant growth and development, whereas flooding treatment began to impact negatively on plant growth and development when the temperature kept rising. The cultivar differences were observed, as the Fianna and Markies performed differently even though the treatments administered were the same. The varied responses of these potato cultivars because of the treatment application were also evident in the quantities of each metabolite produced. For example, asparagine metabolite was not produced under drought irrigation treatment, yet it was produced in large quantities under both normal and flooding irrigation treatments. Similarly, the correlation of metabolites to different plant growth parameters, also between treatment groups and metabolites, signifies how whole plants respond metabolically to water stress (that is, drought, flooding, or a normal water regime). However, despite biochemical changes, the essential nutrients were still produced by these potato cultivars. This research further showed that the content of crude protein in potato tubers is not only strongly dependent on cultivated potato cultivars but also on the interaction of different abiotic conditions. The findings from this study should assist in identifying drought-or flood-resistant potato cultivars that could provide high quality yields despite changing climatic conditions.Lolu cwaningo lwenzelwe ukuphenya imiphumela yokwanda kwezinga lokushisa komoya, kuhlangene nesomiso sezulu esiguquguqukayo esihlanganisa izikhukhula noma isomiso, ngenxa yokuthuthukiswa kwenqala sizinda okanye ukuncola kwomkhathi ngenxa yezimboni. Ucwaningo lwenziwe iminyaka emithathu. Unyaka wokuqala (2016) wawubheka ukuthi lungenziwa kanjani lolugcwaningo, ngokutshala amazambane angu 32. Iminyaka emibili eyalandela (2017 no 2018 amazambane angu 108 unyaka ngamunye) yabe seyenza lona uqobo lolucwaningo. Imiphumela yalolu cwaning yenziwe ngokusebenzisa i LC-MS yona uyaveza 98 metabolites ngokuhlaziya amacembe amazambane. Amazambane uqobo wona ahlaziywa kusetshenziswa i NMR. Ukuhlaziya lemiphumela ekukhiqizweni kwezambane, izinhlobo ezimbili zezimbewu zamazambane eMarkies kanye neFianna zisetshenzisiwe kulolucwaningo. Ngaphezu kwalokho, imiphumela yengcindezi emvelweni nase zilwanyaneni ngenxa yokuguquka kwesimo sezulu ihlaziyiwe kulamazambane amabili, ukuze kubonakale ukuthi izinga lemisoco kanye nezakhamuzimba alithikamazekanga. Lemiphumela yacwanisiswa futhi kwaqhathaniswa nezinga lokukhula kwezitshalo zalamazambane, neqophelo lomkhiqizo, kanye nobungako besivuno sawo. Umthelela wokwanda kwezinga lokushisa nokutholakala kwamanzi noma imvula wabonakala ekukhuleni kwesitshalo kanye nokusabela kwentuthuko yala mazambane. Nakuba ucwaningo lwenziwa ezindlini zokugcina izitshalo ngonyaka ka 2017 kanyenoka 2018, amazinga okushisa komkhathi yatholwa kwaSouth African Weather Services (SAWS).
Imininigwane ngokushisa evela kwa-SAWS iveza ukuthi ukunyuka kwezinga lokushisa okulingana no 0.75 ° C kuqoshwe ngonyaka wokuhlola ka 2018. Ngenxa yalokho kunyuka kwezinga lokushisa komkhathi, kucatshangwa ukuthi isimo sezulu sinomthelela endleleni lamazambane akhule ngayo kanye nomkhiqizo ogcine utholakele ongabanga muhle ngonyaka ka 2018 uma uqhathaniswa nolona owatholakala ngonyaka ka 2017. Umehluko walezitshalo zalamazambane ubulokhu uqashelwe futhi uqoshwa njalo ngosuku luka 14 (amaviki amabili). Ngaphezu kwalokho kunobufakazi bokuthi izinhlobo ezahlukene zamazambane azithikanyezwa yisimo sezulu ngendlela efanayo njengoba iFianna neMarkies yenza ngokuhlukile nakuba izimo ezazibhekene zamo, njengamazinga okushisa kanye nenani lamanzi ezaziwathola lalifana. Izimpendulo ezihlukene zalezi zitshalo zamazambane ngenxa yokuniselwa ngezindlela ezahlukahlukene ziphinde zabonakala enanini esivuno kanye nezinga leqophelo lalesosivuno. Isibonelo, izakha muzimba ezithile, njenge asparajini, ayizange ikhiqizwe ngaphansi kokwehliswa kwenani lamanzi uma kuniselwa ukuze kubesezingeni lesomiso, kwalandele okwezikhukhula; kodwa yakhiqizwa ngobuningi futhi eqophelweni eliphezulu ngaphansi kokunisela ngezinga lamanzi adingwa ngamazambane ukuze akhule. Ngokufanayo, ukuqhathaniswa kwezakhamzimba ezitholakale kulamazambane nenani lawo yabe yehlukahluekene, ihambisana yokukhula kwezitshalo, kanye nokuniselwa okwakweneka. Lokho kubonisa ngokusobala ukuthi izitshalo zonke zisabela kanjani ekushintshashintsheni kwezimo zokushisha namanzi okube yingcindezi kuzo (lezozimo zihlanganisa, amazinga okushisa komkhathi, izikhukhula, noma isomiso). Kodwa-ke, okuhle ukuthi naphezu kwezinguquko zezimo zezule ezazihlasele lamazambane uma ekhula, izakhamuzimba nemisoco ebalulekile yakhiqizwa yilamazamazambane omabili. Lolu cwaningo luphinde lwathola ukuthi amzinga esakhamuzimba iprotheyini engahluziwe kulamazambane ayincikile nje kuphela ezitshalweni kodwa futhi nasekusebenzelaneni kwezimo ezihlukahlukene zesimo senncindezi esenziwa yizinambuzane nokunukubezeka kwemvelo. Okutholwe kulolu cwaningo kufanele kusize ekuhlonzeni izithombo zamazambane ezingakwazi ukumelana nesomiso sezulu esiguquguqukayo, esihlanganisa izikhukhula noma isomiso, noma ukunyuka kwamazinga okushisa okungenzeka nganoma yisiphi isikwathi futhi kudonse izinsuku ezingaziwa.Ndzavisiso lowu wu endliwe ku lavisisa hi vuyelo bya ku ngeteleleka ka mahiselo ya xibakabaka, swi pfangana na dyandza kumbe ndhambi eka ku kula, ku hluvuka na prodakthivhithi ya ti-cultivar ta mazambana ya Markies na Fianna. Kasi hi tlhelo rinwana vuyelo bya ntshikilelo wa abiotic eka profayili ya metabolomic ya ti-cultivar ta mazambana mambirhi ku endliwe ndzavisiso hi wona na ku pimanisa nkoka ya wona, ku kula na ntshovelo lowu nga kumeka hi wona Nkucetelo wa ku ngeteleleka ka mahiselo na ku kumeka ka mati na swona swi langutiwile hi ku kula ka swimila na ndlela ya angulo wa mazambana lawa. Hambileswi ndzavisiso wu endliwe eka ti-greenhouse exikarhi ka 2017 na 2018, malembe ya xikamibisiso, vutivi bya mahiselo ya xibakabaka swi kumekile eka va nhlangano wa South African Weather Services (SAWS). Vutivi bya mahiselo byo huma eka va SAWS byi kombise leswo ku ngeteleleka ka mahiselo hi 0.75% swi kandziyisiwile eka lembe ra ku endliwa ka xikambisiso hi 2018. Hikokwalaho ku langutiwa ka xikambisiso xa dyandza, swi hlangana na ku ya ehenhla ka mahiselo, swi kombise ku vaviseka ka ku kula ka swimila na nhluvuko wa swona, kasi ku langutana na ndhambi swi ve na vuyelo byo biha eka ku kula na nhluvuko wa swimila loko mahiselo ya karhi ya ya ehenhla. Ku hambana ka cultivar swi langutiwile tanihiloko Fianna na Markies swi tirhe hi ku hambana hambi loko swilo leswi swi langutiwe hi ndlela yo fanana. Ku angula ko hambana ka ti-cultivar ta mazambana lawa tanihi vuyelo bya ku tirhisiwa ka ku langutiwa ka leswi na swona swi vonake swi ri vumbhoni eka vunyingi bya metabolite leyi yi nga humesiwa. Xikombiso, asparagine metabolite a yi humesiwangi ehansi ka ku endliwa ka ncheleto hi nkarhi wa dyandza, kambe ku humesiwa hi vunyingi lebyikulu ehansi ka ku endliwa hi nkarhi wa ntolovelo na ncheleto wa ndhambi. Hikufanana na swona, ku fambelana ka ti-metabolite eka ku kula ko hambana ka swimila, na le xikarhi ka ku ongoriwa ka mitlawa na ti-metabolite swi kombise nkoka wa vuanguri bya swimila hinkwawo hi metabolikali eka ntshikilelo hi swa mati (hileswo, dyandza, ndhambi kumbe nkarhi wa ntolovelo hi ku kumeka ka mati). Kambe, hambi ku va na ku cinca ka biochemical, tinutriyente leti faneleke a ta ha humesiwangi hi ti-cultivar ta mazambana lawa. Ndzavisiso lowu wu tlhele wu komba leswo vundzeni bya protheyini ya rihlaza eka tichubara ta mazambane a ti titshegangi ngopfu eka ti-cultivar ta mazambana lama byariwaka kambe ti tlhela ti titshega na swiyimo swa ti-abiotic to hambana. Mimbuyelo ya ndzavisiso lowu yi fanele ku pfuneta ti-cultivar ta mazambana lama ya khodelelaku eka dyandza kumbe ndhambi, leswi swi nga pfunetaku ku va na ntshovelo wa nkoka hambi loko swiyimo swa tshamelo-maxelo swi karhi swi cinca.Ph D. (Agriculture)Agriculture and Animal Healt
The impact of the Johannesburg Stock Exchange's alternative exchange on listed firm's performance and entrepreneurship
No full textThis study’s primary objective is to determine the impact that the JSE’s AltX has on listed firm’s performance and the level of entrepreneurship in South Africa. Its secondary objective was to quantitatively determine whether there exists a link between increased capitalisation of the AltX and the expansionary drive of listed firms, as well as to ascertain the impact that the listing requirements of the AltX has on the broad-based black economic empowerment (B-BBEE) score performance of listed firms. In order to achieve the methodological objectives of this study, mixed methods was used to measure this phenomenon which led to the development of an integrated model for the JSE’s AltX listed firms, as well as for intending small and medium enterprises (SMEs) that might want to list. Accordingly, the researcher employed pragmatic research paradigm and conducted two types of analysis. Firstly, quantitative analysis which is based on primary and secondary data was conducted followed by a qualitative analysis based on a qualitative semi-structured case study. It was found that the JSE's AltX positively impacts on the performance of listed firms and the level of entrepreneurship in South Africa. Most especially as increased capitalisation levels was positively linked with the expansionary drive of these registered firms. And that the listing requirements of the AltX had a net positive effect on the B-BBEE score performance of these companies. Practically, by virtue of being listed many SMEs would generate enough capital and buzz to facilitate their expansion. This study also contributes to new knowledge by recommending that the JSE's AltX develop a custom-made business-friendly targeted listing procedure. Just as policy makers are encouraged to create a one-stop-shop investment portal which would streamline the activities of government agencies for the benefit of Small, Medium and Micro-Enterprises (SMMEs) in South Africa. The researcher proposes that future research would extend beyond South Africa, across the SADC, Africa or even across continents.
Besides, a 3-level multi-level modelling (MLM) equation testing procedure was conducted to test the efficacy of firm listing, using IBM SPSS Statistics version 27 statistical software package. Quantitative analysis, comprising: quantitative analysis of primary data from survey questionnaire (investigated whether location or sector impacts on firm performance), and quantitative analysis of secondary data (determined if the number of both SMMEs and the JSE's AltX listed companies impacts on firm performance and the level of entrepreneurship in South Africa). Using participants' sample from sixty JSE's AltX listed firms who were either CEOs/directors/top management team members, and ten interviewees (i.e. for the qualitative analysis, comprising: qualitative analysis of primary data from semi-structured case study), this study's triangulated findings and conclusions became more valid and reliable. Evidence provided by the ensuing econometric analysis suggests that: Firstly, firms that are listed on the JSE’s AltX were more likely to perform better than their unlisted peers (i.e. both formal and informal SMMEs). Thus, this helped listed firms to improve their company’s performance, corporate profile, loan amount and profits, as well as assisted in securing a major investor for the firm. Besides, it was observed that the variation in the dataset occurred within sectors between the JSE's AltX variable parameters at Level 1. This positively impacted on the AltX market capitalisation, total number of employed personnel, foreign assets, as well as the total equity and liabilities of the JSE's AltX listed firms. Secondly, listing on the JSE’s AltX was found to be positively associated with the level of entrepreneurship in South Africa. There was evidence that listing boosted the level of creativity and innovation in South Africa, as well as encouraged entrepreneurial risk taking, and also increased business confidence levels. Furthermore, it was observed that the variation in the dataset occurred within sectors between the JSE's AltX variable parameters at Level 1. Likewise, the turnover, AltX market capitalisation, the total investments and loans, as well as the earnings yield of the JSE's AltX listed firms were positively linked with the level of entrepreneurship in South Africa.
Thirdly, the rising share capitalisation of listed firms on the AltX was linked to an increased likelihood for company expansion. In addition, listing led to international firm exposure and industry position consolidation. However, the corporate bonds and equities sold by these listed firms on the AltX did not guaranty the long-term sustainability of their business. Also, it was observed that the variation in the dataset occurred within sectors between the JSE's AltX variable parameters at Level 1. Correspondingly, the qualitative case analysis indicated that listing on the AltX led to a high yield but with lower multiples, higher return on equity, joint ventures and acquisitions, share ownership dilution, debt reduction, more capital disbursement and risk diversification, and it also led to firm growth and economic development, which was good. Fourthly, higher compliance requirements for listing on the AltX, increased the likelihood that there would be improvements in quoted B-BBEE performance score. Equally, the implementation of good governance systems like the B-BBEE by listed firms made them more attractive to stakeholders. On the other hand, when the B-BBEE score of these listed firms becomes the regressand, listing had an undesirable effect on their value added, patents and trademarks in relation to company performance. This study therefore opens-up a new vista for examining the performance of listed firms in South Africa, which is a significant contribution to new knowledge.D. Phil. (Management Studies (Entrepreneurship))Business Managemen
Audio assisted learning materials and their effect on secondary school learners’ performance in the Vhembe District of the Limpopo province in South Africa
No full textThe purpose of this study was to establish “the effect of audio-assisted learning materials on secondary school learners’ performance in the Vhembe District of the Limpopo Province in South Africa.” This study was a descriptive survey to examine the effect of audio-assisted learning materials on secondary school learners’ performance in the rural areas. A quantitative approach was used for data collection. A questionnaire was used as a research instrument and was designed for teachers. The sample size of the research was 101 teachers from four secondary schools. The quantitative collected data was analysed using the Statistical Package for Social Science (SPSS) software. The findings revealed that rural secondary schools in the Vhembe District of the Limpopo Province are currently using verbal, social, and solitary learning styles as the methods of learning. The results also showed that secondary schools required adequate learning and teaching resources to improve learners’ learning performance. The findings further indicated that with advanced learning and teaching methods, learners can benefit more by improving their reading fluency, improving digital literacy skills, grasping proper pronunciation and tone, and reducing distractions while learning. The study recommends that the establishment of audio-assisted learning materials should be considered as a method that could help learners to improve their learning performance; furthermore, audio-assisted learning materials should be introduced in schools across the country of South Africa. Due to the COVID -19 pandemic and the restrictions that came with it, it was impossible to conduct an experimental study with learners to complete the study as aimed at the start. The study was limited as the researcher had to apply high standards of ethics to keep both the researcher and respondents safe. Therefore, learners were excluded from this study as the teachers were responding on behalf of learners as they observe learners every day during school hours.M.A. (Information Science)Information Scienc
Graphene oxide quantum dots-based nanocomposites for wastewater treatment
Get PDFThe presence of new emerging pollutants in freshwater systems poses potentially serious threats to human health, food production, ecosystems and hinder economic growth. Emerging personal care products and pharmaceuticals, pesticides, wide range of industrial chemicals, as well as climate change, all pose new threats to water quality. With largely long-term effects on people, the environment and ecosystems being unclear. The main aim of the thesis was to synthesize graphene oxide quantum dots (GQDs) using a facile one-pot method through the pyrolysis of citric acid and deploy them in the removal of emerging wastewater pollutants.
GQDs were initially applied alone as photocatalysts in the photodegradation of pollutants in real wastewater spiked with an organic dye (Brilliant black). The photodegradation and removal efficiency of the GQDs were improved by conjugating differently shaped zinc oxide (ZnO) nanoparticles to the GQDs. The design strategy and approach were based on the GQDs to acting as reservoirs for the photogenerated electrons that could subsequently enhance the lifetime of the electrons, exploiting the ability of GQDs to absorb light as well as the π → π∗ transition in GQDs that allow more harvesting of sunlight. Upon conjugation of the GQDS with ZnO, there was a significant decrease in the band gaps, along with an improvement in photocatalytic efficiency. The conjugates of ZnO-GQDs showed enhanced bacterial inhibition against the bacterial strains tested (Bacillus cereus (B. cereus), Pseudomonas aeruginosa (P. aeruginosa), Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli)). When PAA was employed as a synergistic oxidant on the GQDs; radicals that were not prone to quenching in complex water matrices were produced (acetylperoxyl and peroxyl radicals CH3C(=O)OO• and CH3C(=O)O•). PAA exhibited disinfectant capabilities that were not entirely dependent on pH and did not generate toxic disinfection by-products (DBPs) in the treated effluent. To mitigate the limitations of a slurry photocatalytic system, the GQDs were embedded in polyethersulfone (PES), and the fabricated membranes were tested in a hybrid-filtration-advanced oxidation processes where the performance of the fabricated membrane was compared to that of a commercial membrane and water quality parameters were evaluated to determine the quality of the water.
GQDs were found to be promising materials for conjugation with other photocatalysts to form heterojunctions with increased photocatalytic activity under visible light irradiation. When embedded in polymeric membranes, the activity of the GQDs was not lost and the membrane could perform a dual AOPs/filtration function. This is important for the application of the membranes in real wastewater treatment applications etc.Chemistr
Macro environment determinants affecting the availability of artemisinin-based combination therapies in Uganda
Get PDFResearch paperPurpose – Artemisinin-based combination therapies (ACTs) have been developed to treat uncomplicated malaria. However, scanty studies exist to inform the role of macro factors in explaining the nonavailability of ACT in developing countries. Therefore, this paper aims to evaluate the different macro-environment factors affecting the availability of ACTs in the public hospital setting. Design/methodology/approach – This study applied a quantitative methodological approach and structural equation modeling (SEM) to test hypotheses statistically. SEM examines linear causal relationships among variables while accounting for measurement error. Confirmatory factor analysis (CFA) was used to assess model reliability. CFA and SEM were used to determine the shared variance-covariance of variables, define the latent construct and provide a more precise way to account for the error variances associated with the variables, which, if untested, could lead to biased parameter estimates. This was guided by the data collected from 40 general public hospitals with 283 respondents. Findings – This study’s results support a model for promoting social-cultural, technological and legal factors. The availability of ACTs is significantly affected by legal factors. Improving legal aspects by a unit can enhance ACT availability by 0.59. Political factors scored the least, and they do not influence the availability of malaria drugs. Research limitations/implications – The design was quantitative and cross-sectional. Future research could be longitudinal with a mixed-method approach and consider other external stakeholders. Practical implications – Reducing the impact of the nonavailability of antimalarial drugs in general public hospitals requires a holistic concerted and coordinated supply chain approach that tackles the political, economic, social-cultural norms, technological and legal factors.Colleges of Economic and Management Science
Direct and indirect speech acts
No full textThis OER explains the concepts "direct and indirect speech acts"Afrikaans and Theory of Literatur