Synthesis and evaluation of phosphonated N-heteroarylcarboxamides as DOXP-reductoisomerase (DXR) inhibitors
- Authors: Bodill, Taryn , Conibear, Anne C , Blatch, Gregory L , Lobb, Kevin A , Kaye, Perry T
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/448939 , vital:74772 , xlink:href="https://doi.org/10.1016/j.bmc.2010.11.062"
- Description: The diethyl esters and disodium salts of a range of heteroarylcarbamoylphosphonic acids have been prepared and evaluated as analogues of the highly active DOXP-reductoisomerase (DXR) inhibitor, fosmidomycin. Computer-simulated docking studies, Saturation Transfer Difference (STD) NMR analysis and enzyme inhibition assays have been used to explore enzyme-binding and -inhibition potential, while in silico analysis of the DXR active site has highlighted the importance of including a well-parameterised metal co-factor in docking studies and has revealed the availability of an additional binding pocket to guide future drug design.
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Synthesis and photophysical behaviour of tantalum and titanium phthalocyanines in the presence of gold nanoparticles
- Authors: Chauke, Vongani P , Arslanoglu, Yasin , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247545 , vital:51593 , xlink:href="https://doi.org/10.1016/j.jphotochem.2011.04.020"
- Description: We report on the synthesis of 2,(3)- (peripheral) and 1,(4)- (non-peripheral) (2-mercaptopyridine)phthalocyanine complexes of titanium (IV) oxide (5 and 6 respectively), and tantalum (III) hydroxide (7, peripheral only), their photochemical and photophysical parameters and the photocatalytic oxidation of cyclohexene in the presence of gold nanoparticles (AuNPs). The singlet oxygen quantum yield values increased in the presence of AuNPs, for complexes 5 and 6. The percentage conversion values for cyclohexene using 5, 6 and 7 were 27%, 20% and 14%, respectively. These values increased considerably in the presence of AuNPs, except complex for 7. The products obtained include cyclohexene oxide, 2-cyclohexen-1-ol, 2-cyclohexene-1-one and 1,2-cyclohexanediol. Low values of singlet oxygen quantum yields favour the formation of 1,2-cyclohexanediol.
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Synthesis and photophysical properties of a novel zinc photosensitizer and its gold nanoparticle conjugate
- Authors: Moeno, Sharon , Antunes, Edith M , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247100 , vital:51546 , xlink:href="https://doi.org/10.1016/j.jphotochem.2011.07.007"
- Description: The peripherally tetra substituted zinc phthalocyanine with 1,6-hexanedithiol as substituent (THdTZnPc, 3) was synthesized and is reported for the first time in this work. The potential of this zinc complex as a suitable photosensitizer for use in photodynamic therapy was determined through the investigation of the photophysical and photochemical properties. In this work complex 3 is attached to gold nanoparticles through the terminal thiol groups of the phthalocyanine resulting in a 3-AuNP conjugate whose photophysicochemical properties are investigated. Fluorescence lifetimes were determined using time correlated single photon counting and they show an increase in the abundance of the monomeric species (τ2) for the Pc in the 3-AuNP conjugate: ∼1 and 0.71 (with respective lifetimes 2.69 ns and 2.86 ns) compared to the free complex 3 with abundances of 0.12 and 0.13 (with respective lifetimes 3.36 ns and 3.28 ns) in DMSO and DMF, respectively.
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Synthesis and photophysical studies of CdTe quantum dot-monosubstituted zinc phthalocyanine conjugates
- Authors: D'Souza, Sarah , Antunes, Edith M , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247825 , vital:51621 , xlink:href="https://doi.org/10.1016/j.ica.2010.12.027"
- Description: The linkage of unsymmetrically monosubstituted 4-aminophenoxy zinc phthalocyanine (ZnAPPc, 5) to CdTe quantum dots capped with mercaptopropionic acid (MPA), L-cysteine (L-cys) or thioglycolic acid (TGA) has been achieved using the coupling agents ethyl-N(3-dimethylaminopropyl) carbodiimide and N-hydroxy succinimide, which facilitate formation of an amide bond to form the QD–ZnAPPc-linked conjugate. The formation of the amide bond was confirmed using Raman and IR spectroscopies. Atomic force microscopy (AFM) and UV–Vis spectroscopy were used further to characterise the conjugate. Förster resonance energy transfer (FRET) resulted in stimulated emission of ZnAPPc in both the linked (QD–ZnAPPc-linked) and mixed (QD:ZnAPPc-mixed) conjugates. The linked L-cys and TGA QDs conjugates (QD–ZnAPPc-linked) gave the largest FRET efficiencies hence showing the advantages of covalent linking. Fluorescence quantum yields of QDs were decreased in QD:ZnAPPc-mixed and QD:ZnAPPc-linked.
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Synthesis and photophysical studies of monocarboxy phthalocyanines containing quaternizable groups
- Authors: Arslanoğlu, Yasin , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/246992 , vital:51535 , xlink:href="https://doi.org/10.1016/j.poly.2011.08.009"
- Description: This work reports on the synthesis and photophysical properties of novel unsymmetrically substituted monocarboxy magnesium (MgPc, 3), aluminum (ClAlPc, 4) and unmetallated (H2Pc, 5) phthalocyanines. Magnesium phthalocyanine (3) was converted into water soluble quaternized derivative (QMgPc, 6) by reaction with methyl iodide. The synthesized phthalocyanines were characterized by IR, UV–Vis, NMR, mass spectrometry and elemental analyses. Photophysical and photochemical studies were carried out in order to determine the potential of the complexes as photosensitizers for use in photodynamic therapy. Triplet quantum yields ranged from 0.37 to 0.40 and triplet lifetimes from 110 to 140 μs in DMSO.
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Synthesis and photophysical studies of phthalocyanine–gold nanoparticle conjugates
- Authors: Nombona, Nolwazi , Antunes, Edith M , Litwinski, Christian , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/248438 , vital:51686 , xlink:href="https://doi.org/10.1039/C1DT11151E"
- Description: This work reports on the synthesis, characterization and photophysical studies of phthalocyanine–gold nanoparticle conjugates. The phthalocyanine complexes are: tris-(5-trifluoromethyl-2-mercaptopyridine)-2-(carboxy)phthalocyanine (3), 2,9,17,23-tetrakis-[(1, 6-hexanedithiol) phthalocyaninato]zinc(II) (8) and [8,15,22-tris-(naptho)-2(amidoethanethiol) phthalocyanato] zinc(II)(10). The gold nanoparticles were characterized using transmission electron microscopy, X-ray diffraction, atomic force microscopy and UV-vis spectroscopy where the size was confirmed to be ∼5 nm. The phthalocyanine Au nanoparticle conjugates showed lower fluorescence quantum yield values with similar fluorescence lifetimes compared to the free phthalocyanines. The Au nanoparticle conjugates of 3 and 10 also showed higher triplet quantum yields of 0.69 to 0.71, respectively. A lower triplet quantum yield was obtained for the conjugate compared to free phthalocyanine for complex 8. The triplet lifetimes ranged from 70 to 92 μs for the conjugates and from 110 to 304 μs for unbound Pc complexes.
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Synthesis, characterization and application of monocarboxy-phthalocyanine-single walled carbon nanotube conjugates in electrocatalysis
- Authors: Mugadza, Tawanda , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247399 , vital:51577 , xlink:href="https://doi.org/10.1016/j.poly.2011.04.020"
- Description: In this paper we report on the synthesis, characterization and use of monocarboxy-phthalocyanine-single walled carbon nanotube conjugates in the electrocatalysis of amitrole and diuron. UV–Vis, FTIR and XRD spectroscopies were used in the characterization of cobalt(II)-tris(benzyl-mercapto)-mono(carboxyphenoxy)-phthalocyanine conjugates (CoMCPc–PA-SWCNT(linked)), while AFM was used to show changes in surface morphologies of the modified electrodes. Cyclic voltammetry and chronoamperometry were used for the electrocatalytic oxidation of amitrole and diuron on the modified glassy carbon electrode. The catalytic rate constants for amitrole and diuron were found to be 1.83 × 106 and 1.99 × 106 M−1 s−1, respectively. The linear range for both was 1.0 × 10−5–2.0 × 10−4 M, with sensitivities of 5.10 and 3.70 A mol−1 L cm−2 for amitrole and diuron, respectively. The limits of detection were estimated to be 0.14 and 0.20 μM for amitrole and diuron, respectively, using the 3δ notation.
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Synthesis, characterization, and photophysical properties of novel ball-type dinuclear and mononuclear containing four 1, 1′-binaphthyl-8, 8′-diol bridged metallophthalocyanines with long triplet state lifetimes
- Authors: Canlıca, Mevlude , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/248406 , vital:51683 , xlink:href="https://doi.org/10.1039/C0DT01749C"
- Description: The syntheses of new ball-type dinuclear Si(IV)(CH3COO)2 and Ti(IV)O phthalocyanines and two different mononuclear Zn(II) and Ti(IV)O phthalocyanines containing four 1,1′-binaphthyl-8,8′-diol substituents on the peripheral positions are described. The structures of these compounds were characterized using the elemental analyzes, UV-Vis, FT-IR, 1H NMR and mass spectroscopies. The ΦF values are 0.14, 0.10, 0.04, 0.02, 0.07; ΦT values are 0.69, 0.71, 0.85, 0.33, 0.71 for 7–11, respectively. All complexes showed very long triplet lifetimes with τT 7510, 3190, 2880, 2370, 9470 μs for 7–11 in DMSO, respectively.
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Tartarus: A honeypot based malware tracking and mitigation framework
- Authors: Hunter, Samuel O , Irwin, Barry V W
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/428629 , vital:72525 , https://d1wqtxts1xzle7.cloudfront.net/96055420/Hunter-libre.pdf?1671479103=andresponse-content-disposi-tion=inline%3B+filename%3DTartarus_A_honeypot_based_malware_tracki.pdfandExpires=1714722666andSignature=JtPpR-IoAXILqsIJSlmCEvn6yyytE17YLQBeFJRKD5aBug-EbLxFpEGDf4GtQXHbxHvR4~E-b5QtMs1H6ruSYDti9fIHenRbLeepZTx9jYj92to3qZjy7UloigYbQuw0Y6sN95jI7d4HX-Xkspbz0~DsnzwFmLGopg7j9RZSHqpSpI~fBvlml3QQ2rLCm4aB9u8tSW8du5u~FiJgiLHNgJaPzEOzy4~yfKkXBh--LTFdgeAVYxQbOESGGh9k5bc-LDJhQ6dD5HpXsM3wKJvYuVyU6m83vT2scogVgKHIr-t~XuiqL35PfI3hs2c~ZO0TH4hCqwiNMHQ8GCYsLvllsA__andKey-Pair-Id=APKAJLOHF5GGSLRBV4ZA
- Description: On a daily basis many of the hosts connected to the Internet experi-ence continuous probing and attack from malicious entities. Detection and defence from these malicious entities has primarily been the con-cern of Intrusion Detection Systems, Intrusion Prevention Systems and Anti-Virus software. These systems rely heavily on known signatures to detect nefarious traffic. Due to the reliance on known malicious signa-tures, these systems have been at a serious disadvantage when it comes to detecting new, never before seen malware. This paper will introduce Tartarus which is a malware tracking and mitigation frame-work that makes use of honeypot technology in order to detect mali-cious traffic. Tartarus implements a dynamic quarantine technique to mitigate the spread of self propagating malware on a production net-work. In order to better understand the spread and impact of internet worms Tartarus is used to construct a detailed demographic of poten-tially malicious hosts on the internet. This host demographic is in turn used as a blacklist for firewall rule creation. The sources of malicious traffic is then illustrated through the use of a geolocation based visuali-sation.
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Teacher professional development with an Education for Sustainable Development focus in South Africa: Development of a network, curriculum framework and resources for teacher education
- Authors: Lotz-Sisitka, Heila
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/128949 , vital:36193 , https://www.ajol.info/index.php/sajee/article/view/122242
- Description: This national case study reports on the development of a national network, curriculum framework and resources for teacher education, with specific focus on the inclusion of environment and sustainability, also known as education for sustainable development (ESD) in the South African teacher education system. It reviews and reports on the history of environment and sustainability education in teacher education, and from this, the national case study begins to conceptualise a new approach to environment and sustainability teacher education within a new curriculum policy environment, and a new teacher education and development policy environment.Action research case study methodology is used to document the first phase of the emergence of this network, and this report covers Phase 1 of the initiative, which covers formation of the network, review of previous practices, three conceptual development pilot studies undertaken in both in-service and pre-service teacher education environments and a piloting of a ‘Train the Trainers’ or ‘Educate the Teacher Educators’ programme, which complements and extends the actual teacher education and development (TED) programme under development.The study highlights critical insights of relevance to the shift to a content referenced curriculum in South Africa, and shows how the ‘knowledge mix’ which forms the foundation of the new Teacher Education Qualifications Framework can be engaged. It also highlights some features of the changing knowledge environment, and what dominant knowledge practices are in environment and sustainability-related teaching and teacher education practices, opening these up for further scrutiny. It raises concerns that dominant knowledge work, while integrating a range of forms of knowledge (as is expected of the teacher education system under the new policy), tends to be limited by content on problems and issues for raising awareness, and fails to develop deeper conceptual depth and understanding of environment and sustainability, as issues based knowledge dominates. Similarly, it fails to support social innovation as a response to environment and sustainability concerns, as awareness raising dominates in dominant knowledge work. The study provides a revised conceptual framework for the Teacher Development Network (TEDN) programme, with guidance on key elements necessary to take the programme forward in Phase 2.
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Tebello Nyokong "As chemists, we are designers"
- Authors: Nolan, Cathy
- Date: 2011
- Language: English
- Type: Article , text
- Identifier: vital:7201 , http://hdl.handle.net/10962/d1006385
- Description: What is the common thread running through denim jeans, cancer and pesticides? None springs to mind, yet when chemist Tebello Nyokong describes her fascinating research, a link begins to emerge: light. A specialist in nanochemistry, Nyokong is using laser in ways that could revolutionize not only the diagnosis and treatment of cancer but also water purification.
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Tebello Nyokong 'As chemists, we are designers'
- Authors: Nolan, Cathy
- Date: 2011
- Subjects: Nyokong, Tebello , L’Oreal–UNESCO Awards for Women in Science
- Language: English
- Type: Article , text
- Identifier: vital:7183 , http://hdl.handle.net/10962/d1006272 , Nyokong, Tebello , L’Oreal–UNESCO Awards for Women in Science
- Description: What is the common thread running through denim jeans, cancer and pesticides? None springs to mind, yet when chemist Tebello Nyokong describes her fascinating research, a link begins to emerge: light. A specialist in nanochemistry, Nyokong is using laser in ways that could revolutionize not only the diagnosis and treatment of cancer but also water purification. Born in Lesotho, Tebello Nyokong is Professor of Medicinal Chemistry and Nanotechnology at Rhodes University in South Africa and Director of the Nanotechnology Innovation Centre for Sensors (Mintek). In 2009, she was one of the five Laureates of the 2009 L’Oreal–UNESCO Awards for Women in Science.
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Temperature activated ionic conductivity in gallium and indium phthalocyanines
- Authors: San, Sait Eren , Okutan, Mustafa , Nyokong, Tebello , Durmus, Mahmut , Ozturk, Birol
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247686 , vital:51607 , xlink:href="https://doi.org/10.1016/j.poly.2010.12.047"
- Description: The effects of introducing gallium and indium metals into phthalocyanine molecules were investigated via temperature and frequency dependent dielectric spectroscopy. The dielectric properties of Ga(III) and In(III) phthalocyanine pellets were measured at frequencies from 1 kHz to 1 MHz in the temperature range 300–530 K. The temperature dependence of the real part of the dielectric constant suggested that these compounds exhibit semiconductor behavior. The activation energy values were calculated from the Arrhenius plots at different frequencies. A distinct transition in these plots indicated the activation of ionic conductivity at higher temperatures.
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The both-and edition:
- Authors: Garman, Anthea
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/158828 , vital:40232 , https://hdl.handle.net/10520/EJC139379
- Description: This 30th edition of Rhodes Journalism Review is timed and themed for the 2nd World Journalism Education Congress which the School of Journalism and Media Studies is hosting at Rhodes University in Grahamstown from 5 to 7 July.
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The compilation of multilingual concept literacy glossaries at the University of Cape Town: a lexicographical function theoretical approach
- Authors: Nkomo, Dion , Madiba, Mbulungeni
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67548 , vital:29110 , http://dx.doi.org/10.5788/27-1-1411
- Description: Publisher version , This article proposes a lexicographical approach to the compilation of multilingual concept literacy glossaries which may play a very important role in supporting students at institutions of higher education. In order to support concept literacy, especially for students for whom English is not the native language, a number of universities in South Africa are compiling multilingual glossaries through which the use of languages other than English may be employed as auxiliary media. Terminologies in languages other than English are developed by translating English terms or coining new terms in these languages to exploit the native language competence of most students. The glossary project at the University of Cape Town (UCT) which was conceived under the auspices of the Multilingualism Education Project (MEP) is discussed. It is shown that the UCT glossaries are compiled using methods consistent with those employed in modern lexicography or proffered in lexicographical theory. The lexicographical function theory is specifically used to account for the glossaries and their production. It is suggested that modern lexicography can provide useful guidance for the production of glossaries, given that the earliest glossaries constitute the humble beginnings of lexicography.
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The contribution made by Mr Justice EF Watermeyer to South African tax jurisprudence
- Authors: Thackwell, Robert Colin
- Date: 2011
- Language: English
- Type: text , Thesis , Masters , MCom
- Identifier: vital:881 , http://hdl.handle.net/10962/d1001635
- Description: The objective of this thesis is to highlight the colossal contributions made by the late Justice Watermeyer to South African tax jurisprudence. His contributions are viewed from a practical application point of view as well as from a statutory interpretative perspective. The style and technique with which he delivered his judgments are also considered to be a contribution in their own right. The core of this thesis is the analysis of seven of Justice Watermeyer‟s most influential judgments. The development and application of the principle or principles developed in each of these seven judgments is then traced chronologically through case law up until recent judgments. It is most notable that each and every phrase contained in section 11(a) of the Income Tax Act has been interpreted by Justice Watermeyer. These interpretations are still viewed as correct statements of the applicable law and will continue to be referred to on a regular basis given the fact that section 11(a) is one of the most widely contested provisions in the Income Tax Act. Several references to his approach to statutory interpretation are made through the course of the case analyses. Whilst significant evidence of a purposive oriented approach to interpretation appears in some judgments, such evidence is lacking in others. An absolute or conclusive submission in terms of his approach to statutory interpretation is not sufficiently supported. His style of judgment is also referred to and commented on, with particular focus placed on his use of illustrative examples. The contribution to South African tax law by Justice Watermeyer is found to be nothing short of enormous. He was and continues to be influential with respect to section 11(a),the definition of gross income in section 1, common law principles of tax avoidance as well as the interpretation of statutory laws of tax avoidance. It is anticipated that some of his interpretations with respect to statutory rules of tax avoidance will be referred to when the relatively new anti-avoidance provisions become the subject of litigation.
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The determinants of happiness among race groups in South Africa
- Authors: Ebrahim, Amina , Botha, Ferdi , Snowball, Jeanette D
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68589 , vital:29291 , http://www.essa2011.org.za/fullpaper/essa2011_2182.pdf
- Description: Publisher version , Economic indicators, like GDP per capita, are commonly used as indicators of welfare. However, they have a very limited and narrow scope, excluding many potentially important welfare determinants, such as health, relative income and religion - not surprising since they were not originally designed to fill this role. There is thus growing acceptance, and use of, subjective measure of wellbeing, (called ‘happiness’ measures) both worldwide and in South Africa. Happiness economics does not propose to replace income based measure of wellbeing, but rather attempts to compliment them with broader measures, which can be important in making policy decisions that optimise societal welfare. This paper tests for differences in subjective wellbeing between race groups in South Africa, and investigates the determinants of self-rated life satisfaction (happiness) for each group. Using the 2008 National Income Dynamics Study (NIDS) data, descriptive methods (ANOVA) and an ordered probit model are applied. Results indicate that reported happiness differs substantially among race groups, with black South Africans being the least happy group despite changes since the advent of democracy in 1994. Higher levels of educational attainment increase satisfaction for the whole sample, and women are generally less happy than men (particularly black women). As found in many other studies, unemployed people have lower levels of life satisfaction than the employed, even when controlling for income and relative income. The determinants of happiness are also different for each race group: While white South Africans attached greater importance to physical health; employment status and absolute income matter greatly for black people. For coloured people and black people, positional status (as measured by relative income) is an important determinant of happiness, with religious involvement significantly contributing to the happiness of Indian people.
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The determinants of household savings in South Africa
- Authors: Simleit, C , Keeotn, Gavin , Botha, Ferdi
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396153 , vital:69154 , xlink:href="https://hdl.handle.net/10520/EJC21526"
- Description: In South Africa, substantial government dissaving as well as poor household savings performance has caused a decline in aggregate savings. Whilst government dissaving has been successfully reversed, household savings continue to fall. Low domestic savings have required South Africa to attract large, volatile portfolio capital inflows to fund a structural current account deficit. Repeated reversals of such inflows have constrained domestic growth and hence an understanding of the factors that have caused this decline in savings is essential in order to formulate policies supportive of sustained higher rates of economic growth. Within the context of the existing literature, this article examines the various determinants of household savings using a vector error-correction model (VECM). The results suggest that interest rates, a wealth effect and upturns in the business cycle all contribute to explaining the decline in household savings. The presence of a partial offset between household savings and government savings also has important implications for the effectiveness of using the fiscal position of the South African government to boost savings.
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The determination of the photosensitizing properties of mercapto substituted phthalocyanine derivatives in the presence of quantum dots capped with mercaptopropionic acid
- Authors: Moeno, Sharon , Antunes, Edith M , Nyokong, Tebello
- Date: 2011
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/247870 , vital:51625 , xlink:href="https://doi.org/10.1016/j.jphotochem.2010.12.009"
- Description: This work reports on the synthesis of several novel water soluble metallophthalocyanines containing Zn2+, In3+, Ga3+ or Si4+ as central metal ions and tetra substituted with mercaptoacetic acid and mercaptopropionic acid. The complexes were characterized using infra red, nuclear magnetic resonance and mass spectroscopies as well as elemental analysis. All the complexes are water soluble but the majority are highly aggregated in water and organic solvents. The complex containing Zn as a central metal and mercaptopropionic acid as a substituent was not aggregated allowing for the determination of photophysical parameters. This complex had triplet state quantum yield of 0.61 in DMF and 0.88 in DMSO while the fluorescence quantum yield was 0.13 in DMSO. The determination of photophysical properties of the complex containing Zn as a central metal and mercaptopropionic acid were carried out in the presence of mercaptopropionic acid capped CdTe quantum dots. There is an increase in triplet state quantum yield from 0.88 (for the phthalocyanine alone) to 0.94 (in the presence of CdTe quantum dots) in DMSO.
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The dialogue between the bench and the bar: implications for adjudicative impartiality
- Authors: Okpaluba, Chuks , Juma, Laurence
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/129078 , vital:36215 , https://hdl.handle.net/10520/EJC53998
- Description: What is the role of the judge in the conduct of a trial? Can he or she engage counsel in legal argument and ask questions on legal issues without breaking the brittle bond of justice or be said to have 'descended into the arena'? Assuming that these actions are permissible, at what point will the judge's dialogue with counsel or line of questioning go beyond permissible limits? These are the questions with which this article grapples. Based on an analysis of the Constitutional Court decisions in State v Basson (2) 2007 (1) SACR 566 (CC) and Bernert v ABSA Bank Ltd 2011 (3) SA 92 (CC), and several Supreme Court of Appeal and other Commonwealth decisions, the article explores the circumstances in which the recusal of judges has been sought, or judicial decisions have been challenged on appeal on the basis of an allegation that there have been violations of the principle of fair hearing as enshrined in the Constitution. The article draws on the 'apprehension of bias' jurisprudence to establish the utility of the presumption of impartiality and the hybrid test of double-reasonableness in contexts where a judge's conduct is in question. The article concludes that the dialogue between the bench and bar is a useful component of adjudication in our adversarial system and should be limited by the rules of impartiality only in very exceptional circumstances.
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