Conjugation of mono-substituted phthalocyanine derivatives to CdSe@ ZnS quantum dots and their applications as fluorescent-based sensors
- Adegoke, Oluwasesan, Nyokong, Tebello
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189842 , vital:44936 , xlink:href="https://doi.org/10.1016/j.synthmet.2013.11.016"
- Description: Unsymmetrically substituted derivatives of aluminium amino phthalocyanines were synthesized for the first time, fully characterized and conjugated to CdSe@ZnS quantum dots (QDs). The conjugates were employed as fluorescence-based sensors for anion sensing. Among the anions that enhanced the fluorescence of the probe, fluoride ion was chosen as the test ion to test the efficacy of the probe. Förster resonance energy transfer from the QDs to the phthalocyanine was observed as an indication for the fluorescence quenching of the QDs upon binding to the phthalocyanine. The fluorescence of the linked QDs was progressively enhanced, and linearly proportional to increasing concentrations of fluoride ion. The type of substituent attached to the phthalocyanine ring influenced the efficiency of fluorescence enhancement. The proposed nanoprobe has been employed to detect fluoride ion in cell culture medium and tap water.
- Full Text:
- Date Issued: 2014
- Authors: Adegoke, Oluwasesan , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189842 , vital:44936 , xlink:href="https://doi.org/10.1016/j.synthmet.2013.11.016"
- Description: Unsymmetrically substituted derivatives of aluminium amino phthalocyanines were synthesized for the first time, fully characterized and conjugated to CdSe@ZnS quantum dots (QDs). The conjugates were employed as fluorescence-based sensors for anion sensing. Among the anions that enhanced the fluorescence of the probe, fluoride ion was chosen as the test ion to test the efficacy of the probe. Förster resonance energy transfer from the QDs to the phthalocyanine was observed as an indication for the fluorescence quenching of the QDs upon binding to the phthalocyanine. The fluorescence of the linked QDs was progressively enhanced, and linearly proportional to increasing concentrations of fluoride ion. The type of substituent attached to the phthalocyanine ring influenced the efficiency of fluorescence enhancement. The proposed nanoprobe has been employed to detect fluoride ion in cell culture medium and tap water.
- Full Text:
- Date Issued: 2014
Conscientious objection to performing same-sex marriage in South Africa
- Authors: Kruuse, Helen
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/129186 , vital:36228 , https://doi.org/10.1093/lawfam/ebu001
- Description: This article considers whether public servants should be exempt from South Africa’s equality provisions and anti-discrimination legislation in solemnizing same-sex marriages. In order to deal with this question, the article analyses the treatment of freedom of conscience and conscientious objection by comparing the solemnization of same-sex marriage by public servants, with another public service: that of terminations of pregnancy. While each situation will inevitably turn on the particular circumstances of the case, I argue that there should be a content-neutral guiding principle (as well as consistency) in dealing with these situations. The issue in each situation is narrowed to whether a civil servant’s personal convictions can override the state’s secular obligations in providing a service, and whether there is room for a qualified right to conscientious objection. By analysing the matter in this way, it is clear that the unqualified statutory exemption clause in South Africa’s Civil Union Act is constitutionally objectionable.
- Full Text: false
- Date Issued: 2014
- Authors: Kruuse, Helen
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/129186 , vital:36228 , https://doi.org/10.1093/lawfam/ebu001
- Description: This article considers whether public servants should be exempt from South Africa’s equality provisions and anti-discrimination legislation in solemnizing same-sex marriages. In order to deal with this question, the article analyses the treatment of freedom of conscience and conscientious objection by comparing the solemnization of same-sex marriage by public servants, with another public service: that of terminations of pregnancy. While each situation will inevitably turn on the particular circumstances of the case, I argue that there should be a content-neutral guiding principle (as well as consistency) in dealing with these situations. The issue in each situation is narrowed to whether a civil servant’s personal convictions can override the state’s secular obligations in providing a service, and whether there is room for a qualified right to conscientious objection. By analysing the matter in this way, it is clear that the unqualified statutory exemption clause in South Africa’s Civil Union Act is constitutionally objectionable.
- Full Text: false
- Date Issued: 2014
Conspecific alarm cue sensitivity by the estuarine calanoid copepod, Paracartia longipatella
- Wasserman, Ryan J, Kramer, Rachel, Vink, Tim J F, Froneman, P William
- Authors: Wasserman, Ryan J , Kramer, Rachel , Vink, Tim J F , Froneman, P William
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68062 , vital:29194 , https://doi.org/10.1111/aec.12135
- Description: Publisher version , Sensitivity to chemical cues associated with predation threat has been well observed in many freshwater zooplankters, yet few studies have highlighted such sensitivity in eury- and stenohaline metazoans. We aimed to assess sensitivity to conspecific chemical alarm cues in the estuarine copepod, Paracartia longipatella. Alarm cues associated with predation have been shown to have population level effects on certain zooplanktonic species. As such, we assessed the occurrence of such effects on population dynamics of P.longipatella over a 12 day period. Using experimental in situ mesocosms, we compared P.longipatella adult, copepodite and nauplii numbers between three treatments; one inoculated with conspecific alarm cues, one containing direct predation pressure (zooplanktivorous fish), and a control treatment containing no predation threat. Trends in population abundances were similar between the direct predation and alarm cue treatments for the six days of the experiment, decreasing in abundance. During the latter half of the study, however, P.longipatella abundances in the alarm cue treatment increased, while those in the presence of direct predation continued to decrease. In the treatment absent of any predation threat, P.longipatella abundances increased consistently over time for the duration of the study. We suggest that P.longipatella are indeed sensitive to conspecific alarm cues associated with predation threat. Furthermore, we propose that prolonged exposure to conspecific alarm cues in the absence of any real threat results in a reduction in sensitive to these cues.
- Full Text: false
- Date Issued: 2014
- Authors: Wasserman, Ryan J , Kramer, Rachel , Vink, Tim J F , Froneman, P William
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68062 , vital:29194 , https://doi.org/10.1111/aec.12135
- Description: Publisher version , Sensitivity to chemical cues associated with predation threat has been well observed in many freshwater zooplankters, yet few studies have highlighted such sensitivity in eury- and stenohaline metazoans. We aimed to assess sensitivity to conspecific chemical alarm cues in the estuarine copepod, Paracartia longipatella. Alarm cues associated with predation have been shown to have population level effects on certain zooplanktonic species. As such, we assessed the occurrence of such effects on population dynamics of P.longipatella over a 12 day period. Using experimental in situ mesocosms, we compared P.longipatella adult, copepodite and nauplii numbers between three treatments; one inoculated with conspecific alarm cues, one containing direct predation pressure (zooplanktivorous fish), and a control treatment containing no predation threat. Trends in population abundances were similar between the direct predation and alarm cue treatments for the six days of the experiment, decreasing in abundance. During the latter half of the study, however, P.longipatella abundances in the alarm cue treatment increased, while those in the presence of direct predation continued to decrease. In the treatment absent of any predation threat, P.longipatella abundances increased consistently over time for the duration of the study. We suggest that P.longipatella are indeed sensitive to conspecific alarm cues associated with predation threat. Furthermore, we propose that prolonged exposure to conspecific alarm cues in the absence of any real threat results in a reduction in sensitive to these cues.
- Full Text: false
- Date Issued: 2014
Contextualising Curriculum Design and Recontextualising Its Implementation: The Case of Climate Change Education for Southern African Transfrontier Conservation Area Practitioners
- Mukute, Mutizwa, Pesanayi, Tichaona V
- Authors: Mukute, Mutizwa , Pesanayi, Tichaona V
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387173 , vital:68212 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/121965"
- Description: This paper discusses how the climate change education needs of park managers, ecologists, and community development officers in Southern African Development Community (SADC) Transfrontier Conservation Areas (TFCAs) were established through contextual profiling. It subsequently analyses how a curriculum that was designed in response to a contextual profiling process was recontextualised during implementation by the SADC Regional Environmental Education Programme (REEP), with support from German Federal Enterprise for International Cooperation (GIZ). The paper’s purpose is to trace the trajectory of contextualised curriculum development and implementation with a view to identifying how the twin concepts of contextual profiling and recontextualisation were utilised and lessons were learnt. The paper has potential value for educators/trainers interested in increasing the relevance of protected area workplace learning and its congruence to learners’ realities.
- Full Text:
- Date Issued: 2014
- Authors: Mukute, Mutizwa , Pesanayi, Tichaona V
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387173 , vital:68212 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/121965"
- Description: This paper discusses how the climate change education needs of park managers, ecologists, and community development officers in Southern African Development Community (SADC) Transfrontier Conservation Areas (TFCAs) were established through contextual profiling. It subsequently analyses how a curriculum that was designed in response to a contextual profiling process was recontextualised during implementation by the SADC Regional Environmental Education Programme (REEP), with support from German Federal Enterprise for International Cooperation (GIZ). The paper’s purpose is to trace the trajectory of contextualised curriculum development and implementation with a view to identifying how the twin concepts of contextual profiling and recontextualisation were utilised and lessons were learnt. The paper has potential value for educators/trainers interested in increasing the relevance of protected area workplace learning and its congruence to learners’ realities.
- Full Text:
- Date Issued: 2014
Contrasting architecture of key African and Australian savanna tree taxa drives intercontinental structural divergence
- Moncrieff, Glenn R, Lehmann, Caroline E, Schnitzler, Jan, Gambiza, James, Hiernaux, Pierre, Ryan, Casey M, Shackleton, Charlie M, Williams, Richard J, Higgins, Steven I
- Authors: Moncrieff, Glenn R , Lehmann, Caroline E , Schnitzler, Jan , Gambiza, James , Hiernaux, Pierre , Ryan, Casey M , Shackleton, Charlie M , Williams, Richard J , Higgins, Steven I
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180919 , vital:43670 , xlink:href="https://doi.org/10.1111/geb.12205"
- Description: We examined differences in the architecture of African and Australian savanna trees. We sought to attribute variation in tree architecture to current environments, wood density and phylogeny, and thereby elucidate the relative importance of biogeographic idiosyncrasies versus current factors in underpinning architectural differences.
- Full Text:
- Date Issued: 2014
- Authors: Moncrieff, Glenn R , Lehmann, Caroline E , Schnitzler, Jan , Gambiza, James , Hiernaux, Pierre , Ryan, Casey M , Shackleton, Charlie M , Williams, Richard J , Higgins, Steven I
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/180919 , vital:43670 , xlink:href="https://doi.org/10.1111/geb.12205"
- Description: We examined differences in the architecture of African and Australian savanna trees. We sought to attribute variation in tree architecture to current environments, wood density and phylogeny, and thereby elucidate the relative importance of biogeographic idiosyncrasies versus current factors in underpinning architectural differences.
- Full Text:
- Date Issued: 2014
Cosmological efficacy and the politics of Sacred Place: Soli Rainmaking in contemporary Zambia
- Authors: Simbao, Ruth K
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147482 , vital:38642 , https://doi.org/10.1162/AFAR_a_00163
- Description: In this article I analyze cosmological efficacy in light of the politicization and apparent secularization of contemporary annual ceremonies in Zambia, south-central Africa, which are framed by scholars as neotraditional (Lentz 2001), folklorized (van Binsbergen 1994), or retraditionalized (Gould 2005:3, 6) events. My term “festivalization” registers the formalization of Zambian performances such as rituals, harvest festivals, inaugurations, and initiations as annual festival events, but does not imply a pejorative attitude towards cultural change and so-called inauthenticity, as the words “folklorization” or “retraditionalization” seem to do.
- Full Text:
- Date Issued: 2014
- Authors: Simbao, Ruth K
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/147482 , vital:38642 , https://doi.org/10.1162/AFAR_a_00163
- Description: In this article I analyze cosmological efficacy in light of the politicization and apparent secularization of contemporary annual ceremonies in Zambia, south-central Africa, which are framed by scholars as neotraditional (Lentz 2001), folklorized (van Binsbergen 1994), or retraditionalized (Gould 2005:3, 6) events. My term “festivalization” registers the formalization of Zambian performances such as rituals, harvest festivals, inaugurations, and initiations as annual festival events, but does not imply a pejorative attitude towards cultural change and so-called inauthenticity, as the words “folklorization” or “retraditionalization” seem to do.
- Full Text:
- Date Issued: 2014
Critical realist versus mainstream interdisciplinarity
- Authors: Price, Leigh
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391143 , vital:68624 , xlink:href="https://doi.org/10.1179/1476743013Z.00000000019"
- Description: In this paper I argue for the superiority of a critical realist understanding of interdisciplinarity over a mainstream understanding of it. I begin by exploring the reasons for the failure of mainstream researchers to achieve interdisciplinarity. My main argument is that mainstream interdisciplinary researchers tend to hypostatize facts, fetishize constant conjunctions of events and apply to open systems an epistemology designed for closed systems. I also explain how mainstream interdisciplinarity supports oppression and gross inequality. I argue that mainstream interdisciplinarity is not true interdisciplinarity and refer to it accordingly as ‘condisciplinarity’. By way of example, I examine the condisciplinarity of the World Health Organization’s ecological model applied to the issue of men’s violence against women. Specifically, I argue that critical realist interdisciplinarity is preferable because it acknowledges inter alia the empirical, actual and real layers of reality, which allows it to develop depth-explanations of phenomena. In practice, this means that critical realist interdisciplinarity can potentially provide explanations that, compared to condisciplinarity, are broader (include more of the human and non-human context) and deeper (include for example individuals’ conscious and unconscious psychological motivations). In the World Health Organization’s example of the causes of men’s violence against women, condisciplinarity resulted in the absence of historical, global and unconscious aspects of the problem. It is also restricted the analysis to reductive, constant-conjunction based theories of the causes of the problem, specifically ‘risk factors’, thereby providing a relatively shallow explanation for the problem.
- Full Text:
- Date Issued: 2014
- Authors: Price, Leigh
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/391143 , vital:68624 , xlink:href="https://doi.org/10.1179/1476743013Z.00000000019"
- Description: In this paper I argue for the superiority of a critical realist understanding of interdisciplinarity over a mainstream understanding of it. I begin by exploring the reasons for the failure of mainstream researchers to achieve interdisciplinarity. My main argument is that mainstream interdisciplinary researchers tend to hypostatize facts, fetishize constant conjunctions of events and apply to open systems an epistemology designed for closed systems. I also explain how mainstream interdisciplinarity supports oppression and gross inequality. I argue that mainstream interdisciplinarity is not true interdisciplinarity and refer to it accordingly as ‘condisciplinarity’. By way of example, I examine the condisciplinarity of the World Health Organization’s ecological model applied to the issue of men’s violence against women. Specifically, I argue that critical realist interdisciplinarity is preferable because it acknowledges inter alia the empirical, actual and real layers of reality, which allows it to develop depth-explanations of phenomena. In practice, this means that critical realist interdisciplinarity can potentially provide explanations that, compared to condisciplinarity, are broader (include more of the human and non-human context) and deeper (include for example individuals’ conscious and unconscious psychological motivations). In the World Health Organization’s example of the causes of men’s violence against women, condisciplinarity resulted in the absence of historical, global and unconscious aspects of the problem. It is also restricted the analysis to reductive, constant-conjunction based theories of the causes of the problem, specifically ‘risk factors’, thereby providing a relatively shallow explanation for the problem.
- Full Text:
- Date Issued: 2014
Critical spaces: processes of othering in British Institutions of Higher Education
- Authors: Phiri, Aretha
- Date: 2014
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60741 , vital:27824 , http://www.jfsonline.org/issue7-8/articles/phiri/
- Description: Global recession and the economic crisis have affected contemporary British society in predictable ways. But this age of austerity has also unveiled the continued sinister machinations of whiteness. While not necessarily homogeneous, austerity rhetoric, as it is currently conventionally deployed, works to perpetuate white masculinist privilege and further entrenches the normative value of whiteness, while simultaneously masking and marginalizing those ethnic minority populations traditionally othered from mainstream sociopolitical discourse. More specifically, recent austerity measures adversely affect the situation of women and the future of feminist theory and practice in British higher education. This paper investigates and problematizes the deployment of austerity discourse within higher learning for its perpetuation of the normativity and hegemony of a masculinist whiteness, which further disadvantages (white) women and disrupts the practice of feminism(s) in academia.
- Full Text:
- Date Issued: 2014
- Authors: Phiri, Aretha
- Date: 2014
- Language: English
- Type: article , text
- Identifier: http://hdl.handle.net/10962/60741 , vital:27824 , http://www.jfsonline.org/issue7-8/articles/phiri/
- Description: Global recession and the economic crisis have affected contemporary British society in predictable ways. But this age of austerity has also unveiled the continued sinister machinations of whiteness. While not necessarily homogeneous, austerity rhetoric, as it is currently conventionally deployed, works to perpetuate white masculinist privilege and further entrenches the normative value of whiteness, while simultaneously masking and marginalizing those ethnic minority populations traditionally othered from mainstream sociopolitical discourse. More specifically, recent austerity measures adversely affect the situation of women and the future of feminist theory and practice in British higher education. This paper investigates and problematizes the deployment of austerity discourse within higher learning for its perpetuation of the normativity and hegemony of a masculinist whiteness, which further disadvantages (white) women and disrupts the practice of feminism(s) in academia.
- Full Text:
- Date Issued: 2014
Cytotoxicity, phytochemical analysis and antioxidant activity of crude extracts from Rhizomes of Elephantorrhiza Elephantina and Pentanisia Prunelloides
- Mpofu, Smart J, Msagati, Titus A M, Krause, Rui W M
- Authors: Mpofu, Smart J , Msagati, Titus A M , Krause, Rui W M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125097 , vital:35728 , https://doi.org/10.4314/ajtcam.v11i1.6
- Description: Background: Elephantorrhiza elephantina (Ee) and Pentanisia prunelloides (Pp) are two medicinal plants which are widely used to remedy various ailments including diarrhoea, dysentery, inflammation, fever, rheumatism, heartburn, tuberculosis, haemorrhoids, skin diseases, perforated peptic ulcers and sore joints in southern Africa (South Africa, Swaziland, Botswana and Zimbabwe). The following study was conducted to explore the in vitro cytotoxicity, antioxidant properties and phytochemical profile of the two medicinal plants. Materials and Methods: The cytotoxicity of the aqueous and methanol extracts and fractions of both species was studied using the brine shrimp lethality tests (BST) for the first time. Results: The results demonstrated that the lethality (LC50) for crude extracts for both plants ranged between 1.8 and 5.8 ppm and was relatively greater than that for the methanol, ethyl acetate and chloroform fractions of the extracts which ranged between 2.1 ppm and 27 ppm. This suggested that crude extracts were more potent than their respective fractions, further explaining that the different fractions of phytochemicals in these plant species work jointly (in synergy) to exert their therapeutic efficacy. Both aqueous and methanol extracts of the two medicinal plants demonstrated a high degree of antioxidant capacity against the DPPH radical with the Duh and Yen inhibition percentage ranging between 4.5% and 72%. Phytochemical studies of the rhizome extracts showed that the major compounds present include flavonoids, tannins, anthocyanidins, anthraquinones, triterpenoids (oleanolic acid), the steroidal saponin Diosgenin, the sugars, rhamnose, glucuronic acid, Arabinose and hexoses. Conclusion: This is the first report of the detection and isolation of diosgenin and oleanolic acid from the rhizome extracts of Ee and Pp. All structures were determined using spectroscopic/spectrometric techniques (1H NMR and 13C and LC-ESI-MS) and by comparison with literature data.
- Full Text:
- Date Issued: 2014
- Authors: Mpofu, Smart J , Msagati, Titus A M , Krause, Rui W M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/125097 , vital:35728 , https://doi.org/10.4314/ajtcam.v11i1.6
- Description: Background: Elephantorrhiza elephantina (Ee) and Pentanisia prunelloides (Pp) are two medicinal plants which are widely used to remedy various ailments including diarrhoea, dysentery, inflammation, fever, rheumatism, heartburn, tuberculosis, haemorrhoids, skin diseases, perforated peptic ulcers and sore joints in southern Africa (South Africa, Swaziland, Botswana and Zimbabwe). The following study was conducted to explore the in vitro cytotoxicity, antioxidant properties and phytochemical profile of the two medicinal plants. Materials and Methods: The cytotoxicity of the aqueous and methanol extracts and fractions of both species was studied using the brine shrimp lethality tests (BST) for the first time. Results: The results demonstrated that the lethality (LC50) for crude extracts for both plants ranged between 1.8 and 5.8 ppm and was relatively greater than that for the methanol, ethyl acetate and chloroform fractions of the extracts which ranged between 2.1 ppm and 27 ppm. This suggested that crude extracts were more potent than their respective fractions, further explaining that the different fractions of phytochemicals in these plant species work jointly (in synergy) to exert their therapeutic efficacy. Both aqueous and methanol extracts of the two medicinal plants demonstrated a high degree of antioxidant capacity against the DPPH radical with the Duh and Yen inhibition percentage ranging between 4.5% and 72%. Phytochemical studies of the rhizome extracts showed that the major compounds present include flavonoids, tannins, anthocyanidins, anthraquinones, triterpenoids (oleanolic acid), the steroidal saponin Diosgenin, the sugars, rhamnose, glucuronic acid, Arabinose and hexoses. Conclusion: This is the first report of the detection and isolation of diosgenin and oleanolic acid from the rhizome extracts of Ee and Pp. All structures were determined using spectroscopic/spectrometric techniques (1H NMR and 13C and LC-ESI-MS) and by comparison with literature data.
- Full Text:
- Date Issued: 2014
Dangerous people and places : a community newspaper's constructions of crime
- Authors: Raymond, Leigh Alice
- Date: 2014
- Subjects: Grocott's Mail (Grahamstown, South Africa) , Community newspapers -- South Africa -- Grahamstown , Crime and the press -- South Africa -- Grahamstown , Newspapers -- Objectivity , Mass media policy -- South Africa -- Grahamstown , Social responsibility of business -- South Africa -- Grahamstown , Police and the press -- South Africa -- Grahamstown
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3527 , http://hdl.handle.net/10962/d1013091
- Description: This thesis argues that there is a clear imbalance in the representation of crime in the newspaper, Grocott’s Mail, in Grahamstown, in the Eastern Cape of South Africa. The thesis concludes that the system of marginalisation and segregation which was established during the apartheid era is the foundation for the continued segregation and marginalisation of certain groups of people in Grahamstown as depicted in crime journalism. Previous research shows that not only people, but spaces are marginalised through media representations of crime. As people are represented as dangerous, so too the spaces they occupy become dangerous spaces. Importantly, the research shows that discourses of marginalisation are present in newspaper reports reproducing the discourses prominent in society, and in turn, the newspaper itself perpetuates these marginalising discourses. This extends into the coverage that different crimes receive in newspapers. For instance, the reports show that a middle-class audience will be more concerned with property crime in middle-class neighbourhoods, than other crimes in lower-class neighbourhoods. I argue that not only the type of crime, but the severity, the effect, and the necessity for justice represented by the newspaper, are all largely determined by the region of the crime. Further, I show that the criminal is not only demonised and represented as individually deviant in the reports in the newspaper, but that these representations are made by this newspaper because they are deeply imbedded as a discourse in society. This is partly because this newspaper has taken on a monitorial role, requiring neutral reporting from journalists, and a dedication to surveying the processes of state institutions, like the police and courts. As a result, the ways in which crime is reported on in the newspaper is fairly well fixed, making it difficult for journalists to conceive of different ways of reporting crime. The representations of the criminal justice system that the monitorial media, this newspaper included present, are a careful balance between the interest of the public, and the need to preserve relationships with sources. The monitorial media in general, and this newspaper in particular, represent the criminal justice system. The relationship between the police and the newspaper, and the courts and the media, therefore strongly influences the way in which crime news is reported. In particular, crime news is represented from the perspective of the criminal justice system. This research was carried out using Critical Discourse Analysis, qualitative interviews, and focus group interviews.
- Full Text:
- Date Issued: 2014
- Authors: Raymond, Leigh Alice
- Date: 2014
- Subjects: Grocott's Mail (Grahamstown, South Africa) , Community newspapers -- South Africa -- Grahamstown , Crime and the press -- South Africa -- Grahamstown , Newspapers -- Objectivity , Mass media policy -- South Africa -- Grahamstown , Social responsibility of business -- South Africa -- Grahamstown , Police and the press -- South Africa -- Grahamstown
- Language: English
- Type: text , Thesis , Masters , MA
- Identifier: vital:3527 , http://hdl.handle.net/10962/d1013091
- Description: This thesis argues that there is a clear imbalance in the representation of crime in the newspaper, Grocott’s Mail, in Grahamstown, in the Eastern Cape of South Africa. The thesis concludes that the system of marginalisation and segregation which was established during the apartheid era is the foundation for the continued segregation and marginalisation of certain groups of people in Grahamstown as depicted in crime journalism. Previous research shows that not only people, but spaces are marginalised through media representations of crime. As people are represented as dangerous, so too the spaces they occupy become dangerous spaces. Importantly, the research shows that discourses of marginalisation are present in newspaper reports reproducing the discourses prominent in society, and in turn, the newspaper itself perpetuates these marginalising discourses. This extends into the coverage that different crimes receive in newspapers. For instance, the reports show that a middle-class audience will be more concerned with property crime in middle-class neighbourhoods, than other crimes in lower-class neighbourhoods. I argue that not only the type of crime, but the severity, the effect, and the necessity for justice represented by the newspaper, are all largely determined by the region of the crime. Further, I show that the criminal is not only demonised and represented as individually deviant in the reports in the newspaper, but that these representations are made by this newspaper because they are deeply imbedded as a discourse in society. This is partly because this newspaper has taken on a monitorial role, requiring neutral reporting from journalists, and a dedication to surveying the processes of state institutions, like the police and courts. As a result, the ways in which crime is reported on in the newspaper is fairly well fixed, making it difficult for journalists to conceive of different ways of reporting crime. The representations of the criminal justice system that the monitorial media, this newspaper included present, are a careful balance between the interest of the public, and the need to preserve relationships with sources. The monitorial media in general, and this newspaper in particular, represent the criminal justice system. The relationship between the police and the newspaper, and the courts and the media, therefore strongly influences the way in which crime news is reported. In particular, crime news is represented from the perspective of the criminal justice system. This research was carried out using Critical Discourse Analysis, qualitative interviews, and focus group interviews.
- Full Text:
- Date Issued: 2014
Degradation of Paracetamol and other constituents in Perfalgan®: subtitle if needed. If no subtitle follow instructions in manual
- Authors: Curran,Catherine
- Date: 2014
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/3165 , vital:43181
- Description: Abstract text. 5.1 Background Paracetamol (acetaminophen) is useful for the treatment of mild to moderate pain as well as being opiate–sparing. In recent years the problem of poor solubility of paracetamol in water has been overcome and an intravenous formulation of paracetamol developed. In South Africa this is marketed by Bristol-Myers Squibb as Perfalgan®. Each 500 mg or 1g ampoule of Perfalgan® is recommended for single use only and is to be discarded once opened (Medicines.org, n.d.). This is most likely due to concerns about degradation of paracetamol or other ingredients in the solution once exposed to air and sterility issues. However in South Africa where this drug is expensive, some centers use one ampoule for multiple cases over the course of 12-24 hours. No obvious clinical adverse effects have been reported. 5.2 Objective of study The aim of this study was to examine the practice of using a single vial of Perfalgan® in divided doses over the course of a day for different patients by way of assessing the stability of Perfalgan® on exposure to air. The study has three components, namely: 1. In vitro assessment of paracetamol levels on exposure to air and stressors over time. 2. In vitro assessment of levels of the excipients, namely mannitol and cysteine on exposure to air and stressors over time. 3. Assessment of the lipid permeability of paracetamol in Perfalgan® on exposure to air and stressors over time. C Curran 2014 Degradation of paracetamol and other constituents in Perfalgan® 8 5.3 Methodology High performance liquid chromatography (HPCL-UV) was used to determine the concentration of paracetamol and the presence of degradation products in samples taken at set time periods following exposure of Perfalgan® to air and stressors. Initial work was done using pure paracetamol to determine optimal measurement conditions prior to analysing Perfalgan®. The concentrations of the additives and their degradation products were measured using nuclear magnetic resonance (1 H NMR). Appreciable changes in these could indicate a safety hazard or decreased bioavailability. Finally ultraviolet spectroscopy was performed to assess samples at a wider spectrum of wavelengths, instead of the single wavelength used in HPLC. This was used to assess for degradation products which absorb at different wavelengths and therefore may be missed if HPLC was used alone. Ultraviolet spectroscopy was also used to test bioavailability of the drug via the octanol:water partition coefficient under stressed and unstressed conditions. 5.4 Results The paracetamol in Perfalgan® did not degrade on exposure to air over 24 hours. Neither did it degrade on exposure to acid, alkali, oxidative or heat stress. The HPLC retention time was constantly between 3.17-3.29 minutes. 1 H NMR revealed no change in the formulation of Perfalgan® except for the conversion of the oxygen scavenger cysteine to cystine. The octanol:water partition coefficient likewise stayed constant and was in agreement with the value of 0.46-0.49 quoted in the literature (International Programme on Chemical Safety, 2008; McNeil Consumer Healthcare, 2010). 5.5 Conclusion The paracetamol in Perfalgan® did not degrade on exposure to air and other stressors over 24 hours. The formulation as Perfalgan® was likewise found to be stable. The drug retained its lipid permeability over this period. , Thesis (MMED) -- Faculty of Health Sciences, 2014
- Full Text:
- Date Issued: 2014
- Authors: Curran,Catherine
- Date: 2014
- Language: English
- Type: Masters theses , text
- Identifier: http://hdl.handle.net/11260/3165 , vital:43181
- Description: Abstract text. 5.1 Background Paracetamol (acetaminophen) is useful for the treatment of mild to moderate pain as well as being opiate–sparing. In recent years the problem of poor solubility of paracetamol in water has been overcome and an intravenous formulation of paracetamol developed. In South Africa this is marketed by Bristol-Myers Squibb as Perfalgan®. Each 500 mg or 1g ampoule of Perfalgan® is recommended for single use only and is to be discarded once opened (Medicines.org, n.d.). This is most likely due to concerns about degradation of paracetamol or other ingredients in the solution once exposed to air and sterility issues. However in South Africa where this drug is expensive, some centers use one ampoule for multiple cases over the course of 12-24 hours. No obvious clinical adverse effects have been reported. 5.2 Objective of study The aim of this study was to examine the practice of using a single vial of Perfalgan® in divided doses over the course of a day for different patients by way of assessing the stability of Perfalgan® on exposure to air. The study has three components, namely: 1. In vitro assessment of paracetamol levels on exposure to air and stressors over time. 2. In vitro assessment of levels of the excipients, namely mannitol and cysteine on exposure to air and stressors over time. 3. Assessment of the lipid permeability of paracetamol in Perfalgan® on exposure to air and stressors over time. C Curran 2014 Degradation of paracetamol and other constituents in Perfalgan® 8 5.3 Methodology High performance liquid chromatography (HPCL-UV) was used to determine the concentration of paracetamol and the presence of degradation products in samples taken at set time periods following exposure of Perfalgan® to air and stressors. Initial work was done using pure paracetamol to determine optimal measurement conditions prior to analysing Perfalgan®. The concentrations of the additives and their degradation products were measured using nuclear magnetic resonance (1 H NMR). Appreciable changes in these could indicate a safety hazard or decreased bioavailability. Finally ultraviolet spectroscopy was performed to assess samples at a wider spectrum of wavelengths, instead of the single wavelength used in HPLC. This was used to assess for degradation products which absorb at different wavelengths and therefore may be missed if HPLC was used alone. Ultraviolet spectroscopy was also used to test bioavailability of the drug via the octanol:water partition coefficient under stressed and unstressed conditions. 5.4 Results The paracetamol in Perfalgan® did not degrade on exposure to air over 24 hours. Neither did it degrade on exposure to acid, alkali, oxidative or heat stress. The HPLC retention time was constantly between 3.17-3.29 minutes. 1 H NMR revealed no change in the formulation of Perfalgan® except for the conversion of the oxygen scavenger cysteine to cystine. The octanol:water partition coefficient likewise stayed constant and was in agreement with the value of 0.46-0.49 quoted in the literature (International Programme on Chemical Safety, 2008; McNeil Consumer Healthcare, 2010). 5.5 Conclusion The paracetamol in Perfalgan® did not degrade on exposure to air and other stressors over 24 hours. The formulation as Perfalgan® was likewise found to be stable. The drug retained its lipid permeability over this period. , Thesis (MMED) -- Faculty of Health Sciences, 2014
- Full Text:
- Date Issued: 2014
Dependence on environmental resources and implications for household welfare: evidence from the Kalahari drylands, South Africa
- Thondhlana, Gladman, Muchapondwa, Edwin
- Authors: Thondhlana, Gladman , Muchapondwa, Edwin
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67810 , vital:29149 , https://doi.org/10.1016/j.ecolecon.2014.10.003
- Description: Publisher version , This paper examines dependence on environmental resources and impacts on household welfare among the indigenous San and Mier rural communities neighbouring Kgalagadi Transfrontier Park in South Africa. Data on the various household income types, including environmental income, were collected through a structured survey of 200 households. Environmental income constituted 20% of the total income. The poorest income quintile showed the highest relative dependence on environmental income (31%), though absolute environmental income increased with total income. Poverty analyses showed that poverty incidence and poverty gap would increase by 13 and 7 percentage points respectively without environmental income. Gini-coefficient analyses revealed that income inequality would increase by 6 percentage points for all households if environmental income was excluded. The results generally suggest that environmental income is important for both the poor and the well-off, and wealth accumulation might be tied to resource use. There is a case for promoting sound environmental management, and sustainable and fair resource use in the Kalahari drylands in order to help pull more households out of poverty. Our findings also point to issues of heterogeneity in resource access even among indigenous communities previously thought to be homogenous. These should be key considerations for conservation interventions.
- Full Text: false
- Date Issued: 2014
- Authors: Thondhlana, Gladman , Muchapondwa, Edwin
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67810 , vital:29149 , https://doi.org/10.1016/j.ecolecon.2014.10.003
- Description: Publisher version , This paper examines dependence on environmental resources and impacts on household welfare among the indigenous San and Mier rural communities neighbouring Kgalagadi Transfrontier Park in South Africa. Data on the various household income types, including environmental income, were collected through a structured survey of 200 households. Environmental income constituted 20% of the total income. The poorest income quintile showed the highest relative dependence on environmental income (31%), though absolute environmental income increased with total income. Poverty analyses showed that poverty incidence and poverty gap would increase by 13 and 7 percentage points respectively without environmental income. Gini-coefficient analyses revealed that income inequality would increase by 6 percentage points for all households if environmental income was excluded. The results generally suggest that environmental income is important for both the poor and the well-off, and wealth accumulation might be tied to resource use. There is a case for promoting sound environmental management, and sustainable and fair resource use in the Kalahari drylands in order to help pull more households out of poverty. Our findings also point to issues of heterogeneity in resource access even among indigenous communities previously thought to be homogenous. These should be key considerations for conservation interventions.
- Full Text: false
- Date Issued: 2014
Design of a Network Packet Processing platform
- Pennefather, Sean, Irwin, Barry V W
- Authors: Pennefather, Sean , Irwin, Barry V W
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427901 , vital:72472 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622772_Design_of_a_Network_Packet_Processing_platform/links/5b9a187f92851c4ba8181bd6/Design-of-a-Network-Packet-Processing-platform.pdf
- Description: This paper describes the design considerations investigated in the implementation of a prototype embedded network packet processing platform. The purpose of this system is to provide a means for researchers to process, and manipulate network traffic using an embedded standalone hardware platform, with the provision this be soft-configurable and flexible in its functionality. The performance of the Ethernet layer subsystem implemented using XMOS MCU’s is investigated. Future applications of this prototype are discussed.
- Full Text:
- Date Issued: 2014
- Authors: Pennefather, Sean , Irwin, Barry V W
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427901 , vital:72472 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622772_Design_of_a_Network_Packet_Processing_platform/links/5b9a187f92851c4ba8181bd6/Design-of-a-Network-Packet-Processing-platform.pdf
- Description: This paper describes the design considerations investigated in the implementation of a prototype embedded network packet processing platform. The purpose of this system is to provide a means for researchers to process, and manipulate network traffic using an embedded standalone hardware platform, with the provision this be soft-configurable and flexible in its functionality. The performance of the Ethernet layer subsystem implemented using XMOS MCU’s is investigated. Future applications of this prototype are discussed.
- Full Text:
- Date Issued: 2014
Determinants of managers' attitudes toward employing people with disabilities in small and medium enterprises in Nkonkobe Municipality
- Ntunzi, Bulelwa https://orcid.org/0000-0002-1068-3672
- Authors: Ntunzi, Bulelwa https://orcid.org/0000-0002-1068-3672
- Date: 2014
- Subjects: Discrimination against people with disabilities--South Africa , Discrimination in employment--South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24857 , vital:63662
- Description: In regard to employment, people with disabilities are discriminated. Unfavourable employer attitudes result in discrimination toward people with disabilities. Entering and progressing in employment create a sense of independency, responsibility and build the self-esteem of people with disabilities. This study sought to determine the influence of individualism-collectivism and demographic factors (age, gender, and level of education) of managers’ attitudes toward employing people with disabilities in small and medium enterprises in Nkonkobe Municipality in the Eastern Cape Province. The social and medical model of disability provided a framework for understanding the literature on attitudes toward people with disabilities. Data was collected from 110 respondents in small and medium enterprises using two scales (Individualism-collectivism Scale and Employer Attitudes toward People with Disabilities Scale). Independent t-tests were used to test each of the hypotheses in the study and ANOVA was used for comparisons among variables. No significant differences found in attitudes on individualistic and collectivistic oriented managers toward employing people with disabilities. In addition, no significant differences in attitudes of managers over age, gender and level of education toward employing people with disabilities in small and medium enterprises. People with disabilities can be a benefit to the organisations since their skills and talents can help the organisations to remain stable in the competitive global environment. , Thesis (MCom (IPS)) -- Faculty of Management and Commerce, 2014
- Full Text:
- Date Issued: 2014
- Authors: Ntunzi, Bulelwa https://orcid.org/0000-0002-1068-3672
- Date: 2014
- Subjects: Discrimination against people with disabilities--South Africa , Discrimination in employment--South Africa
- Language: English
- Type: Master's theses , text
- Identifier: http://hdl.handle.net/10353/24857 , vital:63662
- Description: In regard to employment, people with disabilities are discriminated. Unfavourable employer attitudes result in discrimination toward people with disabilities. Entering and progressing in employment create a sense of independency, responsibility and build the self-esteem of people with disabilities. This study sought to determine the influence of individualism-collectivism and demographic factors (age, gender, and level of education) of managers’ attitudes toward employing people with disabilities in small and medium enterprises in Nkonkobe Municipality in the Eastern Cape Province. The social and medical model of disability provided a framework for understanding the literature on attitudes toward people with disabilities. Data was collected from 110 respondents in small and medium enterprises using two scales (Individualism-collectivism Scale and Employer Attitudes toward People with Disabilities Scale). Independent t-tests were used to test each of the hypotheses in the study and ANOVA was used for comparisons among variables. No significant differences found in attitudes on individualistic and collectivistic oriented managers toward employing people with disabilities. In addition, no significant differences in attitudes of managers over age, gender and level of education toward employing people with disabilities in small and medium enterprises. People with disabilities can be a benefit to the organisations since their skills and talents can help the organisations to remain stable in the competitive global environment. , Thesis (MCom (IPS)) -- Faculty of Management and Commerce, 2014
- Full Text:
- Date Issued: 2014
Development and assessment of sustained release stavudine loaded microparticles
- Authors: Zindove, Chiedza Cathrine
- Date: 2014
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54722 , vital:26603
- Description:
Stavudine (D4T) has been used as first line treatment for HIV/AIDS and is part of highly active anti retroviral treatment (HAART). It is an affordable medicine and its use is beneficial in resource limited settings. However D4T exhibits dose dependent side effects that may lead to non-adherence in patients. This study was undertaken to formulate, develop and manufacture a dosage form that could reduce dose dependent side effects by decreasing the dose of D4T but still exhibit antiretroviral (ARV) activity. The use of sustained release (SR) formulations of D4T that ensure constant levels of the D4T in the body would not only optimize therapy but also reduce the incidence of side effects thereby increasing patient adherence. SR microparticles containing 30mg D4T were manufactured and loaded into size 3 hard gelatine capsules prior to analysis. The D4T microparticles were manufactured by microencapsulation using non-aqueous oil-in-oil solvent evaporation approach. D4T-excipient, excipient-excipient interactions and D4T purity were assessed using Infrared Spectroscopy (IR), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Copolymers synthesized from acrylic and methacrylic acid esters viz., Eudragit® RSPO and S100 were used as rate retardant materials and the effect of microcrystalline cellulose (Avicel® PH102) on the microparticles was also investigated. Magnesium stearate was used as a droplet stabilizer and n-hexane was added to harden the microspheres formed in a liquid paraffin continuous phase. The microparticles were optimized using a Box Behnken design and Response Surface Methodology (RSM). The microparticles were characterized in terms of their flow properties and encapsulation efficiency (% EE), in addition to visualization of the surface morphology with Scanning Electron Microscopy. In vitro D4T release studies were performed using USP Apparatus III in media of different pH and the samples were analysed using a validated High Performance Liquid Chromatographic (HPLC) method with ultraviolet (UV) detection that had been developed and optimized using a Central Composite Design (CCD). The method was validated according to ICH guidelines. The IR spectra and DSC thermographs revealed that D4T exhibited thermal stability and there was no evidence of D4T-excipient and excipient-excipient interactions. The microparticles that were produced were white, free flowing and were obtained in a high yield with high encapsulation efficiency. Scanning Electron Microscopy studies revealed that the microparticles were spherical and porous in nature. In vitro D4T release extended to 12 hours and the mechanism of release was established using model dependent methods by fitting the data to a Zero order, First order, Higuchi and Hixson Crowell model. It was observed that the mechanism of D4T release was diffusion-controlled and that the data was best fitted to the Higuchi model with correlation coefficients > 0.9. The release mechanism was confirmed using the Korsmeyer-Peppas model that revealed that most of the formulations exhibited anomalous transport kinetics with the release exponent, n, ranging from 0.5
- Full Text:
- Date Issued: 2014
- Authors: Zindove, Chiedza Cathrine
- Date: 2014
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54722 , vital:26603
- Description:
Stavudine (D4T) has been used as first line treatment for HIV/AIDS and is part of highly active anti retroviral treatment (HAART). It is an affordable medicine and its use is beneficial in resource limited settings. However D4T exhibits dose dependent side effects that may lead to non-adherence in patients. This study was undertaken to formulate, develop and manufacture a dosage form that could reduce dose dependent side effects by decreasing the dose of D4T but still exhibit antiretroviral (ARV) activity. The use of sustained release (SR) formulations of D4T that ensure constant levels of the D4T in the body would not only optimize therapy but also reduce the incidence of side effects thereby increasing patient adherence. SR microparticles containing 30mg D4T were manufactured and loaded into size 3 hard gelatine capsules prior to analysis. The D4T microparticles were manufactured by microencapsulation using non-aqueous oil-in-oil solvent evaporation approach. D4T-excipient, excipient-excipient interactions and D4T purity were assessed using Infrared Spectroscopy (IR), Differential Scanning Calorimetry (DSC) and Thermogravimetric Analysis (TGA). Copolymers synthesized from acrylic and methacrylic acid esters viz., Eudragit® RSPO and S100 were used as rate retardant materials and the effect of microcrystalline cellulose (Avicel® PH102) on the microparticles was also investigated. Magnesium stearate was used as a droplet stabilizer and n-hexane was added to harden the microspheres formed in a liquid paraffin continuous phase. The microparticles were optimized using a Box Behnken design and Response Surface Methodology (RSM). The microparticles were characterized in terms of their flow properties and encapsulation efficiency (% EE), in addition to visualization of the surface morphology with Scanning Electron Microscopy. In vitro D4T release studies were performed using USP Apparatus III in media of different pH and the samples were analysed using a validated High Performance Liquid Chromatographic (HPLC) method with ultraviolet (UV) detection that had been developed and optimized using a Central Composite Design (CCD). The method was validated according to ICH guidelines. The IR spectra and DSC thermographs revealed that D4T exhibited thermal stability and there was no evidence of D4T-excipient and excipient-excipient interactions. The microparticles that were produced were white, free flowing and were obtained in a high yield with high encapsulation efficiency. Scanning Electron Microscopy studies revealed that the microparticles were spherical and porous in nature. In vitro D4T release extended to 12 hours and the mechanism of release was established using model dependent methods by fitting the data to a Zero order, First order, Higuchi and Hixson Crowell model. It was observed that the mechanism of D4T release was diffusion-controlled and that the data was best fitted to the Higuchi model with correlation coefficients > 0.9. The release mechanism was confirmed using the Korsmeyer-Peppas model that revealed that most of the formulations exhibited anomalous transport kinetics with the release exponent, n, ranging from 0.5
- Full Text:
- Date Issued: 2014
Development and evaluation of pictograms on medication labels for patients with limited literacy skills in a culturally diverse multiethnic population:
- Kheir, Nadir, Awaisu, Ahmed, Radoui, Amina, El Badawi, Aya, Jean, Linda, Dowse, Roslind
- Authors: Kheir, Nadir , Awaisu, Ahmed , Radoui, Amina , El Badawi, Aya , Jean, Linda , Dowse, Roslind
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156720 , vital:40041 , https://doi.org/10.1016/j.sapharm.2013.11.003
- Description: Much of the migrant workforce in Qatar is of low literacy level and does not understand Arabic or English, presenting a significant challenge to health care professionals. Medicine labels are typically in Arabic and English and are therefore poorly understood by these migrant workers. To develop pictograms illustrating selected medicine label instructions and to evaluate comprehension of the pictograms or conventional text supported with verbal instructions in foreign workers with low literacy skills.
- Full Text:
- Date Issued: 2014
- Authors: Kheir, Nadir , Awaisu, Ahmed , Radoui, Amina , El Badawi, Aya , Jean, Linda , Dowse, Roslind
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156720 , vital:40041 , https://doi.org/10.1016/j.sapharm.2013.11.003
- Description: Much of the migrant workforce in Qatar is of low literacy level and does not understand Arabic or English, presenting a significant challenge to health care professionals. Medicine labels are typically in Arabic and English and are therefore poorly understood by these migrant workers. To develop pictograms illustrating selected medicine label instructions and to evaluate comprehension of the pictograms or conventional text supported with verbal instructions in foreign workers with low literacy skills.
- Full Text:
- Date Issued: 2014
Development of Graphene/CdSe Quantum Dots‐Co Phthalocyanine Nanocomposite for Oxygen Reduction Reaction
- Nyoni, Stephen, Nyokong, Tebello
- Authors: Nyoni, Stephen , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189944 , vital:44950 , xlink:href="https://doi.org/10.1002/elan.201400372"
- Description: Nanocomposites containing CdSe quantum dots, tetra(4-(4,6-diaminopyrimidin-2-ylthio) phthalocyaninatocobalt(II)) (CoPyPc) and reduced graphene nanosheets (rGNS) were devoloped and used for the modification of a glassy carbon electrode. Characterization of the nanocomposites was done by transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses. Cyclic voltammetry (CV) was used for electrochemical characterization of the prepared nanocomposite for oxygen reduction reaction. The oxygen reduction activity for rGNS/CdSe-CoPyPc nanocomposite was found to be superior over the individual nanomaterials in this study. The activity of the nanocomposite towards oxygen reduction was also tested for tolerance to methanol crossover effect using chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) studies.
- Full Text:
- Date Issued: 2014
- Authors: Nyoni, Stephen , Nyokong, Tebello
- Date: 2014
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189944 , vital:44950 , xlink:href="https://doi.org/10.1002/elan.201400372"
- Description: Nanocomposites containing CdSe quantum dots, tetra(4-(4,6-diaminopyrimidin-2-ylthio) phthalocyaninatocobalt(II)) (CoPyPc) and reduced graphene nanosheets (rGNS) were devoloped and used for the modification of a glassy carbon electrode. Characterization of the nanocomposites was done by transmission electron microscopy (TEM) and X-ray diffraction (XRD) analyses. Cyclic voltammetry (CV) was used for electrochemical characterization of the prepared nanocomposite for oxygen reduction reaction. The oxygen reduction activity for rGNS/CdSe-CoPyPc nanocomposite was found to be superior over the individual nanomaterials in this study. The activity of the nanocomposite towards oxygen reduction was also tested for tolerance to methanol crossover effect using chronoamperometry (CA) and electrochemical impedance spectroscopy (EIS) studies.
- Full Text:
- Date Issued: 2014
Development of styrene based imprinted sorbents for selective clean-up of metalloporphyrins in organic media
- Authors: Awokoya, Kehinde Nurudeen
- Date: 2014
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/54521 , vital:26580
- Description: Most crude oils contain traces of vanadium and nickel complex with porphyrins (VTPP and NTPP) within their asphaltene fraction. Although these metals are only present in trace quantities, they have a significant and detrimental impact on the refining process by degrading the quality of intermediate and end products. Therefore, their selective removal is highly desirable. This thesis presents the development of nickel porphyrin, nickel vanadyl porphyrin imprinted nanofibers and vanadyl porphyrin imprinted polymer (MIP) particles for application as selective sorbents. Computational model based on the combination of molecular dynamics simulations and quantum mechanics was successfully applied to the styrene functional monomer selection. The particle was prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The morphologies, thermal stabilities and porosities of the imprinted sorbents were studied using SEM, TGA, and BET nitrogen gas adsorption. Chloroform was found to swell the polymer particles to a higher degree than methanol and acetonitrile. The adsorption characteristics of the imprinted sorbents best fitted with Freundlich isotherm model. The imprinted sorbents recorded high extraction efficiencies (EEs) of > 99 % in selectively extracting the metalloporphyrins. The impact of the template on the affinity of recognition for NTPP was evaluated. The results showed that the NTPP adsorption capacity increased as the molar ratio of NTPP to styrene was increased from 1:1 to 3:1. The optimal ratio of template to functional monomer which yielded the best specific affinity and highest recovery (99.9 %) was 3:1. The effects of trifluoroacetic acid (TFA), dichloromethane (DCM), dimethyl sulphoxide (DMSO), pentane (PEN) on electro-spinnability of the polymer solutions and the morphological appearance of the nanofibers were investigated. The imprinted nanofibers exhibited the same selectivity specialism for both NTPP and VTPP. A remarkable stability in relation to reusability was observed when imprinted nanofibers were used, as they could be reused nine times without incurring any significant loss in removal efficiency. The results were validated by analysing a certified reference material. The imprinted sorbents were therefore found to be selective sorbents that are well suited for handling trace metals in organic media.
- Full Text:
- Date Issued: 2014
- Authors: Awokoya, Kehinde Nurudeen
- Date: 2014
- Language: English
- Type: text , Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10962/54521 , vital:26580
- Description: Most crude oils contain traces of vanadium and nickel complex with porphyrins (VTPP and NTPP) within their asphaltene fraction. Although these metals are only present in trace quantities, they have a significant and detrimental impact on the refining process by degrading the quality of intermediate and end products. Therefore, their selective removal is highly desirable. This thesis presents the development of nickel porphyrin, nickel vanadyl porphyrin imprinted nanofibers and vanadyl porphyrin imprinted polymer (MIP) particles for application as selective sorbents. Computational model based on the combination of molecular dynamics simulations and quantum mechanics was successfully applied to the styrene functional monomer selection. The particle was prepared by bulk polymerization and the nanofibers by a novel approach combining molecular imprinting and electrospinning technology. The morphologies, thermal stabilities and porosities of the imprinted sorbents were studied using SEM, TGA, and BET nitrogen gas adsorption. Chloroform was found to swell the polymer particles to a higher degree than methanol and acetonitrile. The adsorption characteristics of the imprinted sorbents best fitted with Freundlich isotherm model. The imprinted sorbents recorded high extraction efficiencies (EEs) of > 99 % in selectively extracting the metalloporphyrins. The impact of the template on the affinity of recognition for NTPP was evaluated. The results showed that the NTPP adsorption capacity increased as the molar ratio of NTPP to styrene was increased from 1:1 to 3:1. The optimal ratio of template to functional monomer which yielded the best specific affinity and highest recovery (99.9 %) was 3:1. The effects of trifluoroacetic acid (TFA), dichloromethane (DCM), dimethyl sulphoxide (DMSO), pentane (PEN) on electro-spinnability of the polymer solutions and the morphological appearance of the nanofibers were investigated. The imprinted nanofibers exhibited the same selectivity specialism for both NTPP and VTPP. A remarkable stability in relation to reusability was observed when imprinted nanofibers were used, as they could be reused nine times without incurring any significant loss in removal efficiency. The results were validated by analysing a certified reference material. The imprinted sorbents were therefore found to be selective sorbents that are well suited for handling trace metals in organic media.
- Full Text:
- Date Issued: 2014
Diagnosing the sexual pattern of Diplodus cervinus hottentotus (Pisces: Sparidae) from southern Angola
- Winkler, Alexander C, Santos, Carmen V D, Potts, Warren M
- Authors: Winkler, Alexander C , Santos, Carmen V D , Potts, Warren M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124286 , vital:35589 , https://doi.10.1007/s11160-006-9034-6
- Description: The sexual pattern of Diplodus cervinus hottentotus was investigated in southern Angola. Females were significantly smaller and found in greater numbers, with an adult sex ratio of 1.0:0.7, F:M. Histological observations of preserved gonads indicated that the species is a rudimentary hermaphrodite, possessing a non-functional bisexual ovotestis before maturation. Histological examination of five macroscopically staged ‘bisexual’ individuals revealed that they were functional males with residual ovarian tissue in the gonad, which had persisted from a juvenile bisexual stage. Although empirical population structure and macroscopic observations suggested protogyny, histological evidence suggested otherwise, confirming the need for the use of histology when diagnosing the sexual pattern of sparid fishes.
- Full Text:
- Date Issued: 2014
- Authors: Winkler, Alexander C , Santos, Carmen V D , Potts, Warren M
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124286 , vital:35589 , https://doi.10.1007/s11160-006-9034-6
- Description: The sexual pattern of Diplodus cervinus hottentotus was investigated in southern Angola. Females were significantly smaller and found in greater numbers, with an adult sex ratio of 1.0:0.7, F:M. Histological observations of preserved gonads indicated that the species is a rudimentary hermaphrodite, possessing a non-functional bisexual ovotestis before maturation. Histological examination of five macroscopically staged ‘bisexual’ individuals revealed that they were functional males with residual ovarian tissue in the gonad, which had persisted from a juvenile bisexual stage. Although empirical population structure and macroscopic observations suggested protogyny, histological evidence suggested otherwise, confirming the need for the use of histology when diagnosing the sexual pattern of sparid fishes.
- Full Text:
- Date Issued: 2014
Digital disruption: some instagrams
- Authors: Garman, Anthea
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144558 , vital:38357 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC159516
- Description: I'm going to shamelessly pinch someone else's language to think about the changes and challenges of this media moment we are living through and take the theme for the Mennel Media Exchange (MMX14), organised by Laurie Bley of Duke University and Patrick Conroy of eNCA and held in Johannesburg in July. “ Digital disruption" doesn't fallen into the neat pessimism or optimism so emblematic of our times but does say forcefully that we are all on uncertain ground and need to reconfigure our ways of doing and being in media making, media managing and in education.
- Full Text:
- Date Issued: 2014
- Authors: Garman, Anthea
- Date: 2014
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144558 , vital:38357 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC159516
- Description: I'm going to shamelessly pinch someone else's language to think about the changes and challenges of this media moment we are living through and take the theme for the Mennel Media Exchange (MMX14), organised by Laurie Bley of Duke University and Patrick Conroy of eNCA and held in Johannesburg in July. “ Digital disruption" doesn't fallen into the neat pessimism or optimism so emblematic of our times but does say forcefully that we are all on uncertain ground and need to reconfigure our ways of doing and being in media making, media managing and in education.
- Full Text:
- Date Issued: 2014