Evolutionary retention of defensive lateral pedal glands in the smallest siphonariid limpet (Gastropoda: Pulmonata)
- Pinchuck, Shirley C, Allanson, Brian R, Hodgson, Alan N
- Authors: Pinchuck, Shirley C , Allanson, Brian R , Hodgson, Alan N
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443312 , vital:74107 , https://hdl.handle.net/10520/EJC183115
- Description: Despite its cryptic habitat and habits, light and transmission electron microscopy has revealed that like many other siphonariids Siphonaria compressa, the smallest species of this genus, possesses lateral pedal glands. The pear-shaped glands (about 120 µm long Ã? 70 µm maximum diameter) open via a pore, and are multicellular with three types of secretory cell that surround a central lumen. The glands of this minute pulmonate limpet are similar in structure to its larger relatives, suggesting that they are defensive in function.
- Full Text:
- Date Issued: 2015
- Authors: Pinchuck, Shirley C , Allanson, Brian R , Hodgson, Alan N
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/443312 , vital:74107 , https://hdl.handle.net/10520/EJC183115
- Description: Despite its cryptic habitat and habits, light and transmission electron microscopy has revealed that like many other siphonariids Siphonaria compressa, the smallest species of this genus, possesses lateral pedal glands. The pear-shaped glands (about 120 µm long Ã? 70 µm maximum diameter) open via a pore, and are multicellular with three types of secretory cell that surround a central lumen. The glands of this minute pulmonate limpet are similar in structure to its larger relatives, suggesting that they are defensive in function.
- Full Text:
- Date Issued: 2015
Exploring contradictions and absences in mobilizing ‘learning as process' for sustainable agricultural practices
- Authors: Pesanayi, Tichaona
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437008 , vital:73323 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: Water is a fascinating, life-giving being. It flows. It cuts into the earth to create its passage by finding the places where the earth will give. As it meanders it passes through many different contexts, whether at a fastrush-full-blown flood or the trickle of an underground desert stream. It does not demand that the space it moves through is homogenous. It adapts to whatever terrain it finds itself journeying through. Human creatures, dependent as they are on water for their own beings and for life, flock to water like flies to food. We build our cities, our factories and homes on the banks and corners of rivers and draw and drink and use (and abuse) water. We throw in and we take out and the river keeps going until sometimes it doesn’t. Then we worry. Sometimes it is not the lack of flow that worries us but the fact that when we drink it babies become sick, some die and this causes a stir. In South Africa this security, or lack of it, is embedded in the political historical landscape of this land. Water is classified as scarce. Our rainfall is low in comparison to other countries. In South Africa, during apartheid this scarce resource was not avail able in equal measure to all. The rulers of apartheid South Africa were farmers and miners. They were of British decent, sent to farm the new colony. They were also descended from first colonial settlers arriving from the Nether-lands and then Germany, known colloquially as the Boers. South Africa was divided and redivided until in 1948 the Boers gained independence from British rule and finished the job that the British had started by legalizing the separation of races. Farming was still core to the Boer way of life and this is reflect-ed in the laws that dictated resource use and management, such as the 1956 Water Act No. 54 (RSA, 1956) which gave riparian rights to those that owned land. Water was also subsi-dized to boost the economy, particularly for the large mines, and parastatals such as Eskom (Byrnes, 1996). Water was not only used to ensure that the economy of white South Africa flourished, it also was the landmark of division.
- Full Text:
- Date Issued: 2015
- Authors: Pesanayi, Tichaona
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437008 , vital:73323 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: Water is a fascinating, life-giving being. It flows. It cuts into the earth to create its passage by finding the places where the earth will give. As it meanders it passes through many different contexts, whether at a fastrush-full-blown flood or the trickle of an underground desert stream. It does not demand that the space it moves through is homogenous. It adapts to whatever terrain it finds itself journeying through. Human creatures, dependent as they are on water for their own beings and for life, flock to water like flies to food. We build our cities, our factories and homes on the banks and corners of rivers and draw and drink and use (and abuse) water. We throw in and we take out and the river keeps going until sometimes it doesn’t. Then we worry. Sometimes it is not the lack of flow that worries us but the fact that when we drink it babies become sick, some die and this causes a stir. In South Africa this security, or lack of it, is embedded in the political historical landscape of this land. Water is classified as scarce. Our rainfall is low in comparison to other countries. In South Africa, during apartheid this scarce resource was not avail able in equal measure to all. The rulers of apartheid South Africa were farmers and miners. They were of British decent, sent to farm the new colony. They were also descended from first colonial settlers arriving from the Nether-lands and then Germany, known colloquially as the Boers. South Africa was divided and redivided until in 1948 the Boers gained independence from British rule and finished the job that the British had started by legalizing the separation of races. Farming was still core to the Boer way of life and this is reflect-ed in the laws that dictated resource use and management, such as the 1956 Water Act No. 54 (RSA, 1956) which gave riparian rights to those that owned land. Water was also subsi-dized to boost the economy, particularly for the large mines, and parastatals such as Eskom (Byrnes, 1996). Water was not only used to ensure that the economy of white South Africa flourished, it also was the landmark of division.
- Full Text:
- Date Issued: 2015
Exploring critical realist insights into transformative environmental learning processes in contexts of social-ecological risk
- Authors: Schudel, Ingrid J
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437045 , vital:73326 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: Environment and sustainability are continually recognized for significance to the future of planetary well-being. But the com-plex, cross-cutting transversal nature and associated ‘new-ness’1 of environment and sustainability concerns within edu-cation and training systems raise a number of challenges for education and training systems. In this chapter I explore how critical realist dialectics can help to more fully explain the ab-sence of intermediate pathways in the environment and sus-tain able development ‘sector’ in South Africa and through this analysis raise opportunities for creating more seamless envi-ronmental learning pathways into green jobs, enhancing social justice potential and public good concerns. The chapter situ-ates the discussion within the South African policy discourse of meaningful learning pathways (DHET, 2010) through a study of two priority scarce skills occupations in the environmental sector (environmental scientist and environmental technician). This is used as an example to illustrate systemic disjunctures that demonstrate how environmental learning pathways in and for sustain able development emerge. Using a critical realist lens to understand the absences that denote a relationship away from being allows the chapter to conceptualize absence as central to the real and hence to being (Lotz-Sisitka and Ramsarup, 2012; Bhaskar, 1993). Privileging absence allows me to develop a vantage point that connects being to becom-ing and hence underlines the intent for change inherent within this research. Norrie (2010, p. 28) states that ‘understanding change as a process of absenting of absences as well as the absenting of those structural constraints that keep absences in place . . . lies at the core of change’.
- Full Text:
- Date Issued: 2015
- Authors: Schudel, Ingrid J
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , book chapter
- Identifier: http://hdl.handle.net/10962/437045 , vital:73326 , ISBN 9781315660899 , https://www.routledge.com/Critical-Realism-Environmental-Learning-and-Social-Ecological-Change/Price-Lotz-Sistka/p/book/9780367597689
- Description: Environment and sustainability are continually recognized for significance to the future of planetary well-being. But the com-plex, cross-cutting transversal nature and associated ‘new-ness’1 of environment and sustainability concerns within edu-cation and training systems raise a number of challenges for education and training systems. In this chapter I explore how critical realist dialectics can help to more fully explain the ab-sence of intermediate pathways in the environment and sus-tain able development ‘sector’ in South Africa and through this analysis raise opportunities for creating more seamless envi-ronmental learning pathways into green jobs, enhancing social justice potential and public good concerns. The chapter situ-ates the discussion within the South African policy discourse of meaningful learning pathways (DHET, 2010) through a study of two priority scarce skills occupations in the environmental sector (environmental scientist and environmental technician). This is used as an example to illustrate systemic disjunctures that demonstrate how environmental learning pathways in and for sustain able development emerge. Using a critical realist lens to understand the absences that denote a relationship away from being allows the chapter to conceptualize absence as central to the real and hence to being (Lotz-Sisitka and Ramsarup, 2012; Bhaskar, 1993). Privileging absence allows me to develop a vantage point that connects being to becom-ing and hence underlines the intent for change inherent within this research. Norrie (2010, p. 28) states that ‘understanding change as a process of absenting of absences as well as the absenting of those structural constraints that keep absences in place . . . lies at the core of change’.
- Full Text:
- Date Issued: 2015
Exploring patterns of Facebook usage, social capital, loneliness and well-being among a diverse South African student sample:
- Young, Charles S, Strelitz, Larry N
- Authors: Young, Charles S , Strelitz, Larry N
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143705 , vital:38275 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: There has been much debate over whether the use of social network sites isolate people and truncate their relationships or alternatively, provide beneficial connections with others. This debate has been framed by a growing international literature which explores the triadic relationship between the intensity of use of Facebook to the maintenance of social capital and in turn the relationship between social capital and wellbeing and loneliness. A random list of 1168 Rhodes University students was drawn from the total student body and invited to participate in an online survey. In total, 491 students completed the survey (42% response rate). Hierarchical regression analyses demonstrate that intensity of Facebook usage adds a very small contribution to social capital, is very weakly associated with loneliness, and is not associated with wellbeing. Results contrast with international studies that fail to recognise the extent to which race and class cleavages impact on access to and use of social media.
- Full Text:
- Date Issued: 2015
- Authors: Young, Charles S , Strelitz, Larry N
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143705 , vital:38275 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: There has been much debate over whether the use of social network sites isolate people and truncate their relationships or alternatively, provide beneficial connections with others. This debate has been framed by a growing international literature which explores the triadic relationship between the intensity of use of Facebook to the maintenance of social capital and in turn the relationship between social capital and wellbeing and loneliness. A random list of 1168 Rhodes University students was drawn from the total student body and invited to participate in an online survey. In total, 491 students completed the survey (42% response rate). Hierarchical regression analyses demonstrate that intensity of Facebook usage adds a very small contribution to social capital, is very weakly associated with loneliness, and is not associated with wellbeing. Results contrast with international studies that fail to recognise the extent to which race and class cleavages impact on access to and use of social media.
- Full Text:
- Date Issued: 2015
Exploring the emancipatory potential of nursing practice in relation to sexuality: a systematic literature review of nursing research 2009-2014
- Nhamo-Murire, Mercy, Macleod, Catriona I
- Authors: Nhamo-Murire, Mercy , Macleod, Catriona I
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143650 , vital:38270 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Nurses play an important role in disseminating health information and in the provision of counselling concerning sexuality healthcare settings. There is some evidence, however, that nurses do not always consider issues relating to sexualities in their general practice, and when they do, may feel some discomfort in addressing sexuality. In this paper we report on a systematic review of research on nursing practice in relation to sexualities that appeared in nursing journals in the Web of Science database from 2009-2014. Thirty nine articles, which were published in English and reported on nursing practice in relation to sexualities, were thematically analysed. We focus on what research has been done and how this research may be used in the development of emancipatory nursing practice in relation to sexualities. Despite increasing attention being paid to social justice issues in nursing, the implications of this for nursing practice needs further exploration.
- Full Text:
- Date Issued: 2015
- Authors: Nhamo-Murire, Mercy , Macleod, Catriona I
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143650 , vital:38270 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: Nurses play an important role in disseminating health information and in the provision of counselling concerning sexuality healthcare settings. There is some evidence, however, that nurses do not always consider issues relating to sexualities in their general practice, and when they do, may feel some discomfort in addressing sexuality. In this paper we report on a systematic review of research on nursing practice in relation to sexualities that appeared in nursing journals in the Web of Science database from 2009-2014. Thirty nine articles, which were published in English and reported on nursing practice in relation to sexualities, were thematically analysed. We focus on what research has been done and how this research may be used in the development of emancipatory nursing practice in relation to sexualities. Despite increasing attention being paid to social justice issues in nursing, the implications of this for nursing practice needs further exploration.
- Full Text:
- Date Issued: 2015
Facile synthesis and biological evaluation of assorted indolyl-3-amides and esters from a single, stable carbonyl nitrile intermediate
- Veale, Clinton G L, Edkins, Adrienne L, de la Mare, Jo-Anne, de Kock, Carmen, Smith, Peter J, Khanye, Setshaba D
- Authors: Veale, Clinton G L , Edkins, Adrienne L , de la Mare, Jo-Anne , de Kock, Carmen , Smith, Peter J , Khanye, Setshaba D
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66221 , vital:28919 , https://doi.org/10.1016/j.tetlet.2015.02.090
- Description: publisher version , The synthesis of biologically relevant amides and esters is routinely conducted under complex reaction conditions or requires the use of additional catalysts in order to generate sensitive electrophilic species for attack by a nucleophile. Here we present the synthesis of different indolic esters and amides from indolyl-3-carbonyl nitrile, without the requirement of anhydrous reaction conditions or catalysts. Additionally, we screened these compounds for potential in vitro antimalarial and anticancer activity, revealing 1H-indolyl-3-carboxylic acid 3-(indolyl-3-carboxamide)aminobenzyl ester to have moderate activity against both lines.
- Full Text: false
- Date Issued: 2015
- Authors: Veale, Clinton G L , Edkins, Adrienne L , de la Mare, Jo-Anne , de Kock, Carmen , Smith, Peter J , Khanye, Setshaba D
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/66221 , vital:28919 , https://doi.org/10.1016/j.tetlet.2015.02.090
- Description: publisher version , The synthesis of biologically relevant amides and esters is routinely conducted under complex reaction conditions or requires the use of additional catalysts in order to generate sensitive electrophilic species for attack by a nucleophile. Here we present the synthesis of different indolic esters and amides from indolyl-3-carbonyl nitrile, without the requirement of anhydrous reaction conditions or catalysts. Additionally, we screened these compounds for potential in vitro antimalarial and anticancer activity, revealing 1H-indolyl-3-carboxylic acid 3-(indolyl-3-carboxamide)aminobenzyl ester to have moderate activity against both lines.
- Full Text: false
- Date Issued: 2015
Facile synthesis, spectroscopic and electrochemical properties, and theoretical calculations of porphyrin dimers with a bridging amide-bonded xanthene moiety
- Liang, Xu, Xu, Li, Li, Minzhi, Mack, John, Stone, Justin, Nyokong, Tebello, Jiang, Yu, Kobayashi, Nagao, Zhu, Weihua
- Authors: Liang, Xu , Xu, Li , Li, Minzhi , Mack, John , Stone, Justin , Nyokong, Tebello , Jiang, Yu , Kobayashi, Nagao , Zhu, Weihua
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241390 , vital:50935 , xlink:href="https://doi.org/10.1142/S1088424615500492"
- Description: A free base porphyrin dimer bridged by a flexible amide-bonded xanthene moiety and its binuclear zinc(II) complex zinc(II) complex were synthesized and characterized. Structural characterization by MS and 1H NMR spectroscopy confirmed the bridged porphyrin dimer structure. The properties of the dimers were characterized by IR, UV-visible absorption, fluorescence and magnetic circular dichroism (MCD) spectroscopy, and electrochemistry studies. Theoretical calculations were carried out to analyze the electronic structures of porphyrin dimers with a bridging amide-bonded xanthene moiety.
- Full Text:
- Date Issued: 2015
- Authors: Liang, Xu , Xu, Li , Li, Minzhi , Mack, John , Stone, Justin , Nyokong, Tebello , Jiang, Yu , Kobayashi, Nagao , Zhu, Weihua
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241390 , vital:50935 , xlink:href="https://doi.org/10.1142/S1088424615500492"
- Description: A free base porphyrin dimer bridged by a flexible amide-bonded xanthene moiety and its binuclear zinc(II) complex zinc(II) complex were synthesized and characterized. Structural characterization by MS and 1H NMR spectroscopy confirmed the bridged porphyrin dimer structure. The properties of the dimers were characterized by IR, UV-visible absorption, fluorescence and magnetic circular dichroism (MCD) spectroscopy, and electrochemistry studies. Theoretical calculations were carried out to analyze the electronic structures of porphyrin dimers with a bridging amide-bonded xanthene moiety.
- Full Text:
- Date Issued: 2015
Fish predation regimes modify benthic diatom community structures: experimental evidence from an in situ mesocosm study
- Wasserman, Ryan J, Vink, Tim J F, Dalu, Tatenda, Froneman, P William
- Authors: Wasserman, Ryan J , Vink, Tim J F , Dalu, Tatenda , Froneman, P William
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68052 , vital:29190 , https://doi.org/10.1111/aec.12255
- Description: Publisher version , Diatoms are important primary producers in shallow water environments. Few studies have assessed the importance of biological interactions in structuring these communities. In the present study, benthic diatom community structure in relation to manipulated food webs was assessed using in situ mesocosms, whereby predator-free environments and environments comprising two different fish species were assessed. Zooplankton abundance, settled algal biomass and the diatom community were monitored over a 12‐day period across each of the three trophic scenarios. Differences among treatments over time were observed in zooplankton abundances, particularly copepods. Similarly, the benthic diatom community structure changed significantly over time across the three trophic treatments. However, no differences in total algal biomass were found among treatments. This was likely the result of non‐diatom phytoplankton contributions. We propose that the benthic diatom community structure within the mesocosms was influenced by trophic cascades and potentially through direct consumption by the fish. The study highlights that not only are organisms at the base of the food web affected by predators at the top of the food web, but that predator identity is potentially an important consideration for predator–prey interaction outcomes with consequences for multiple trophic levels.
- Full Text: false
- Date Issued: 2015
- Authors: Wasserman, Ryan J , Vink, Tim J F , Dalu, Tatenda , Froneman, P William
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68052 , vital:29190 , https://doi.org/10.1111/aec.12255
- Description: Publisher version , Diatoms are important primary producers in shallow water environments. Few studies have assessed the importance of biological interactions in structuring these communities. In the present study, benthic diatom community structure in relation to manipulated food webs was assessed using in situ mesocosms, whereby predator-free environments and environments comprising two different fish species were assessed. Zooplankton abundance, settled algal biomass and the diatom community were monitored over a 12‐day period across each of the three trophic scenarios. Differences among treatments over time were observed in zooplankton abundances, particularly copepods. Similarly, the benthic diatom community structure changed significantly over time across the three trophic treatments. However, no differences in total algal biomass were found among treatments. This was likely the result of non‐diatom phytoplankton contributions. We propose that the benthic diatom community structure within the mesocosms was influenced by trophic cascades and potentially through direct consumption by the fish. The study highlights that not only are organisms at the base of the food web affected by predators at the top of the food web, but that predator identity is potentially an important consideration for predator–prey interaction outcomes with consequences for multiple trophic levels.
- Full Text: false
- Date Issued: 2015
Fish utilization of surf-zones. Are they changing? A case study of the sheltered, warm-temperate King’s Beach
- Rishworth, Gavin M, Strydom, Nadine A, Potts, Warren M
- Authors: Rishworth, Gavin M , Strydom, Nadine A , Potts, Warren M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124504 , vital:35619 , https://doi.org/10.1080/15627020.2014.11407616
- Description: Surf-zone fish communities and their shifts over time are generally poorly understood. The aim of this study was to compare the current surf-zone fish assemblage at King’s Beach, South Africa, to a similar study conducted three decades ago, before the collapse of many exploited shore fishes in the region. Beach seine nets (mesh sizes of 10 and 50 mm) were used to target juvenile and adult fishes bimonthly from February to August 2011 over the high tide around sunset. A total of 14 species were recorded in both the 30mand 100mseine nets. The catch in these seine nets was dominated by Pomadasys olivaceus and Liza richardsonii, and this was significantly different to three decades ago, when P. olivaceus, Sarpa salpa and Diplodus capensis dominated the catch. Important linefish species belonging to the Sparidae and Sciaenidae families were significantly smaller and less abundant in this study. Two sparids, S. salpa and Lithognathus mormyrus, which made a large contribution to the surf-zone catch three decades ago were absent during this study. Reasons for the significant shifts in the surf-zone fish community, including overexploitation of the linefish and potential habitat modification, are discussed.
- Full Text:
- Date Issued: 2015
- Authors: Rishworth, Gavin M , Strydom, Nadine A , Potts, Warren M
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124504 , vital:35619 , https://doi.org/10.1080/15627020.2014.11407616
- Description: Surf-zone fish communities and their shifts over time are generally poorly understood. The aim of this study was to compare the current surf-zone fish assemblage at King’s Beach, South Africa, to a similar study conducted three decades ago, before the collapse of many exploited shore fishes in the region. Beach seine nets (mesh sizes of 10 and 50 mm) were used to target juvenile and adult fishes bimonthly from February to August 2011 over the high tide around sunset. A total of 14 species were recorded in both the 30mand 100mseine nets. The catch in these seine nets was dominated by Pomadasys olivaceus and Liza richardsonii, and this was significantly different to three decades ago, when P. olivaceus, Sarpa salpa and Diplodus capensis dominated the catch. Important linefish species belonging to the Sparidae and Sciaenidae families were significantly smaller and less abundant in this study. Two sparids, S. salpa and Lithognathus mormyrus, which made a large contribution to the surf-zone catch three decades ago were absent during this study. Reasons for the significant shifts in the surf-zone fish community, including overexploitation of the linefish and potential habitat modification, are discussed.
- Full Text:
- Date Issued: 2015
Fluorescence behavior and singlet oxygen generating abilities of aluminum phthalocyanine in the presence of anisotropic gold nanoparticles
- Mthethwa, Thandekile, Nyokong, Tebello
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193598 , vital:45351 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
- Date Issued: 2015
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193598 , vital:45351 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
- Date Issued: 2015
Fluorescence behavior and singlet oxygen generating abilities of aluminum phthalocyanine in the presence of anisotropic gold nanoparticles
- Mthethwa, Thandekile, Nyokong, Tebello
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189865 , vital:44941 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
- Date Issued: 2015
- Authors: Mthethwa, Thandekile , Nyokong, Tebello
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189865 , vital:44941 , xlink:href="https://doi.org/10.1016/j.jlumin.2014.09.005"
- Description: Gold nanoparticles (spheres, rods and bipyramids) were synthesized. The nanocrystals were characterized by UV–visible spectrometry, transmission electron microscopy (TEM) and X-ray diffractometry (XRD). The as prepared gold nanoparticles were then conjugated to a quaternized 2,(3)-tetra [2-(dimethylamino) ethanethio] substituted Al(OH) phthalocyanine (complex 1). The conjugation of phthalocyanines with gold nanoparticles resulted in a decrease in the fluorescence quantum yields and lifetimes. Conversely, an increase in the singlet oxygen quantum yields was observed for the conjugated complex 1 in the presence of AuNPs.
- Full Text:
- Date Issued: 2015
Fluorescence Behaviour of an Aluminium Octacarboxy Phthalocyanine-NaYGdF 4
- Taylor, Jessica, Litwinski, Christian, Nyokong, Tebello, Antunes, Edith M
- Authors: Taylor, Jessica , Litwinski, Christian , Nyokong, Tebello , Antunes, Edith M
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189503 , vital:44852 , xlink:href="https://doi.org/10.1007/s10895-015-1539-8"
- Description: Using a methanol assisted thermal decomposition approach, sphere shaped NaYGdF4:Yb/Er upconversion nanoparticles (UCNPs) were successfully synthesized. The chemical, spectroscopic and fluorescence properties of the UCNPs were fully characterized. Characteristic upconversion fluorescence emissions were produced by the NPs in the green, red and NIR regions and the NPs were also shown to possess paramagnetic properties. The influence of the UCNPs on the spectroscopic and fluorescence properties of an aluminium octacarboxy phthalocyanine AlOCPc was investigated. Covalent conjugation to an AlOCPc resulted in a large blue shift of the phthalocyanine’s Q band, which was accompanied by a decrease in the Pc’s fluorescence lifetime in DMSO. By combining the phthalocyanine and upconversion nanoparticle, we present a system capable of multimodal imaging, using both the upconversion nanoparticle’s and phthalocyanine’s emission, and magnetic resonance imaging (as a result of doping the upconversion nanoparticles with Gd3+ ions).
- Full Text:
- Date Issued: 2015
- Authors: Taylor, Jessica , Litwinski, Christian , Nyokong, Tebello , Antunes, Edith M
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/189503 , vital:44852 , xlink:href="https://doi.org/10.1007/s10895-015-1539-8"
- Description: Using a methanol assisted thermal decomposition approach, sphere shaped NaYGdF4:Yb/Er upconversion nanoparticles (UCNPs) were successfully synthesized. The chemical, spectroscopic and fluorescence properties of the UCNPs were fully characterized. Characteristic upconversion fluorescence emissions were produced by the NPs in the green, red and NIR regions and the NPs were also shown to possess paramagnetic properties. The influence of the UCNPs on the spectroscopic and fluorescence properties of an aluminium octacarboxy phthalocyanine AlOCPc was investigated. Covalent conjugation to an AlOCPc resulted in a large blue shift of the phthalocyanine’s Q band, which was accompanied by a decrease in the Pc’s fluorescence lifetime in DMSO. By combining the phthalocyanine and upconversion nanoparticle, we present a system capable of multimodal imaging, using both the upconversion nanoparticle’s and phthalocyanine’s emission, and magnetic resonance imaging (as a result of doping the upconversion nanoparticles with Gd3+ ions).
- Full Text:
- Date Issued: 2015
Food on the Table: Human Responses and Changing Coastal Fisheries in Solomon Islands
- Albert, Simon, Aswani, Shankar, Fisher, Paul L, Albert, Joelle
- Authors: Albert, Simon , Aswani, Shankar , Fisher, Paul L , Albert, Joelle
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/421887 , vital:71893 , xlink:href="https://doi.org/10.1371/journal.pone.0130800"
- Description: Globally the majority of commercial fisheries have experienced dramatic declines in stock and catch. Likewise, projections for many subsistence fisheries in the tropics indicate a dramatic decline is looming in the coming decades. In the Pacific Islands coastal fisheries provide basic subsistence needs for millions of people. A decline in fish catch would therefore have profound impacts on the health and livelihoods of these coastal communities. Given the decrease in local catch rates reported for many coastal communities in the Pacific, it is important to understand if fishers have responded to ecological change (either by expanding their fishing range and/or increasing their fishing effort), and if so, to evaluate the costs or benefits of these responses. We compare data from fish catches in 1995 and 2011 from a rural coastal community in Solomon Islands to examine the potentially changing coastal reef fishery at these time points. In particular we found changes in preferred fishing locations, fishing methodology and catch composition between these data sets. The results indicate that despite changes in catch rates (catch per unit effort) between data collected in 2011 and 16 years previously, the study community was able to increase gross catches through visiting fishing sites further away, diversifying fishing methods and targeting pelagic species through trolling. Such insight into local-scale responses to changing resources and/or fisheries development will help scientists and policy makers throughout the Pacific region in managing the region’s fisheries in the future.
- Full Text:
- Date Issued: 2015
- Authors: Albert, Simon , Aswani, Shankar , Fisher, Paul L , Albert, Joelle
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/421887 , vital:71893 , xlink:href="https://doi.org/10.1371/journal.pone.0130800"
- Description: Globally the majority of commercial fisheries have experienced dramatic declines in stock and catch. Likewise, projections for many subsistence fisheries in the tropics indicate a dramatic decline is looming in the coming decades. In the Pacific Islands coastal fisheries provide basic subsistence needs for millions of people. A decline in fish catch would therefore have profound impacts on the health and livelihoods of these coastal communities. Given the decrease in local catch rates reported for many coastal communities in the Pacific, it is important to understand if fishers have responded to ecological change (either by expanding their fishing range and/or increasing their fishing effort), and if so, to evaluate the costs or benefits of these responses. We compare data from fish catches in 1995 and 2011 from a rural coastal community in Solomon Islands to examine the potentially changing coastal reef fishery at these time points. In particular we found changes in preferred fishing locations, fishing methodology and catch composition between these data sets. The results indicate that despite changes in catch rates (catch per unit effort) between data collected in 2011 and 16 years previously, the study community was able to increase gross catches through visiting fishing sites further away, diversifying fishing methods and targeting pelagic species through trolling. Such insight into local-scale responses to changing resources and/or fisheries development will help scientists and policy makers throughout the Pacific region in managing the region’s fisheries in the future.
- Full Text:
- Date Issued: 2015
Formulation, development and assessment of tenofovir disoproxil fumarate-loaded pellets
- Authors: Dube, Tawanda
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54690 , vital:26600
- Description: Tenofovir disoproxil fumarate (TDF) is a novel nucleotide analog reverse transcriptase inhibitor that is recommended by the WHO for use in first line treatment of HIV infections. Due to the high dose of TDF for anti-retroviral treatment the formulation of a pellet dosage form may improve patient adherence by incorporation of a large dose in a relatively small dosage form. TDF is currently only available in tablet form. A simple, sensitive, selective, rapid, accurate, precise, stability indicating reversed-phase HPLC method was developed and validated in accordance with ICH guidelines and was successfully used for the analysis of TDF raw material and pharmaceutical dosage forms. Preformulation studies included an investigation of TDF-excipient and excipient-excipient interactions with all materials that could potentially be used to produce extruded and spheronized pellets. Nuclear Magnetic Resonance spectroscopy (NMR), Infrared Spectroscopy (IR), Differential Scanning Colorimetry (DSC) and Thermogravimetric analysis were used for identification and purity testing of TDF and all excipients. DSC data revealed that no potential interactions between TDF and the excipients occurred suggesting that incompatibility reactions were unlikely during manufacture and storage. These findings were confirmed by IR analysis that revealed that no physical interaction was likely between any of the excipients used and TDF. DSC data also reveal the existence of the α and β-polymorphs of TDF as evidenced by two enthalpy changes observed on the resultant thermograms. The existence of two polymorphs is unlikely to result in incompatibility and was confirmed by IR analysis. The IR spectra reveal that all characteristic peaks for TDF were present in 1:1 binary mixtures. Therefore TDF is compatible with all excipients tested and thermal analysis confirmed the stability of TDF under manufacturing conditions. The temperature of degradation temperature established through DSC analysis confirmed that degradation during manufacture is unlikely as the temperature of manufacture is lower than that at which degradation occurs. Extrusion and spheronization were the processes used to manufacture TDF pellets as it is a simple and economic approach for production. The effects of extruder and spheronizer speed, amount of spheronization aid and diluents on the pellet size, shape, flow properties and TDF release characteristics were examined. In order to decrease the complexity of analysis and reduce the cost of development a Taguchi orthogonal array design of experiments was successfully applied to evaluate the impact of formulation variables on product characteristics and predict an optimized formulation with a minimum number of experiments. The use of Response Surface Methodology for the development and optimization of pharmaceutical systems, including the optimization of formulation composition, manufacturing processes and/or analytical methods is well established. However the application of RSM requires that accurate, precise and reproducible experimental conditions are used for the generation of reliable data and RSM use is limited due to sensitivity to experimental variability. The benefits of using RSM for formulation optimization include the fact that more than one variable can be investigated at a time and large amounts of information can be generated at the same time ensuring a more efficient process with respect to time and cost. An added advantage of this approach is that mathematical relationships can be generated for the models that are produced and provide formulation scientists with an indication of whether the effect(s) between factors are synergistic or antagonistic. There are several statistical design approaches that use RSM and a Taguchi orthogonal array design was selected for use in this optimization process as fewer experiments are required to generate data for the same number of factors to be investigated when compared to other statistical designs such as Central Composite (CCD) and Box-Behnken designs. The use of RSM clearly demonstrates the impact of different input variables on the % TDF released at 45 min and % TDF loaded into the particles. The amount of sorbitol and Kollidon® CL-M were the only significant variables that affected the % TDF released at 45 min and both excipients had an overall synergistic effect on the in vitro release of TDF. The prediction and manufacture of an optimized formulation led to the production of pellets that met predetermined specifications which was successfully achieved using RSM. The development of a TDF containing pellet dosage form has been achieved and the formulation, manufacture and characterization of the dosage form reveal that the product has the potential to be further developed.
- Full Text:
- Date Issued: 2015
- Authors: Dube, Tawanda
- Date: 2015
- Language: English
- Type: text , Thesis , Masters , MPharm
- Identifier: http://hdl.handle.net/10962/54690 , vital:26600
- Description: Tenofovir disoproxil fumarate (TDF) is a novel nucleotide analog reverse transcriptase inhibitor that is recommended by the WHO for use in first line treatment of HIV infections. Due to the high dose of TDF for anti-retroviral treatment the formulation of a pellet dosage form may improve patient adherence by incorporation of a large dose in a relatively small dosage form. TDF is currently only available in tablet form. A simple, sensitive, selective, rapid, accurate, precise, stability indicating reversed-phase HPLC method was developed and validated in accordance with ICH guidelines and was successfully used for the analysis of TDF raw material and pharmaceutical dosage forms. Preformulation studies included an investigation of TDF-excipient and excipient-excipient interactions with all materials that could potentially be used to produce extruded and spheronized pellets. Nuclear Magnetic Resonance spectroscopy (NMR), Infrared Spectroscopy (IR), Differential Scanning Colorimetry (DSC) and Thermogravimetric analysis were used for identification and purity testing of TDF and all excipients. DSC data revealed that no potential interactions between TDF and the excipients occurred suggesting that incompatibility reactions were unlikely during manufacture and storage. These findings were confirmed by IR analysis that revealed that no physical interaction was likely between any of the excipients used and TDF. DSC data also reveal the existence of the α and β-polymorphs of TDF as evidenced by two enthalpy changes observed on the resultant thermograms. The existence of two polymorphs is unlikely to result in incompatibility and was confirmed by IR analysis. The IR spectra reveal that all characteristic peaks for TDF were present in 1:1 binary mixtures. Therefore TDF is compatible with all excipients tested and thermal analysis confirmed the stability of TDF under manufacturing conditions. The temperature of degradation temperature established through DSC analysis confirmed that degradation during manufacture is unlikely as the temperature of manufacture is lower than that at which degradation occurs. Extrusion and spheronization were the processes used to manufacture TDF pellets as it is a simple and economic approach for production. The effects of extruder and spheronizer speed, amount of spheronization aid and diluents on the pellet size, shape, flow properties and TDF release characteristics were examined. In order to decrease the complexity of analysis and reduce the cost of development a Taguchi orthogonal array design of experiments was successfully applied to evaluate the impact of formulation variables on product characteristics and predict an optimized formulation with a minimum number of experiments. The use of Response Surface Methodology for the development and optimization of pharmaceutical systems, including the optimization of formulation composition, manufacturing processes and/or analytical methods is well established. However the application of RSM requires that accurate, precise and reproducible experimental conditions are used for the generation of reliable data and RSM use is limited due to sensitivity to experimental variability. The benefits of using RSM for formulation optimization include the fact that more than one variable can be investigated at a time and large amounts of information can be generated at the same time ensuring a more efficient process with respect to time and cost. An added advantage of this approach is that mathematical relationships can be generated for the models that are produced and provide formulation scientists with an indication of whether the effect(s) between factors are synergistic or antagonistic. There are several statistical design approaches that use RSM and a Taguchi orthogonal array design was selected for use in this optimization process as fewer experiments are required to generate data for the same number of factors to be investigated when compared to other statistical designs such as Central Composite (CCD) and Box-Behnken designs. The use of RSM clearly demonstrates the impact of different input variables on the % TDF released at 45 min and % TDF loaded into the particles. The amount of sorbitol and Kollidon® CL-M were the only significant variables that affected the % TDF released at 45 min and both excipients had an overall synergistic effect on the in vitro release of TDF. The prediction and manufacture of an optimized formulation led to the production of pellets that met predetermined specifications which was successfully achieved using RSM. The development of a TDF containing pellet dosage form has been achieved and the formulation, manufacture and characterization of the dosage form reveal that the product has the potential to be further developed.
- Full Text:
- Date Issued: 2015
FPGA Based Implementation of a High Performance Scalable NetFlow Filter
- Herbert, Alan, Irwin, Barry V W, Otten, D F, Balmahoon, M R
- Authors: Herbert, Alan , Irwin, Barry V W , Otten, D F , Balmahoon, M R
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427887 , vital:72470 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622948_FPGA_Based_Implementation_of_a_High_Perfor-mance_Scalable_NetFlow_Filter/links/5b9a17a192851c4ba8181ba5/FPGA-Based-Implementation-of-a-High-Performance-Scalable-NetFlow-Filter.pdf
- Description: Full packet analysis on firewalls and intrusion detection, although effec-tive, has been found in recent times to be detrimental to the overall per-formance of networks that receive large volumes of throughput. For this reason partial packet analysis algorithms such as the NetFlow protocol have emerged to better mitigate these bottlenecks. This research delves into implementing a hardware accelerated, scalable, high per-formance system for NetFlow analysis and attack mitigation. Further-more, this implementation takes on attack mitigation through collection and processing of network flows produced at the source, rather than at the site of incident. This research platform manages to scale out its back-end through dis-tributed analysis over multiple hosts using the ZeroMQ toolset. Fur-thermore, ZeroMQ allows for multiple NetFlow data publishers, so that plug-ins can subscribe to the publishers that contain the relevant data to further increase the overall performance of the system. The dedicat-ed custom hardware optimizes the received network flows through cleaning, summarization and re-ordering into an easy to pass form when given to the sequential component of the system; this being the back-end.
- Full Text:
- Date Issued: 2015
- Authors: Herbert, Alan , Irwin, Barry V W , Otten, D F , Balmahoon, M R
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/427887 , vital:72470 , https://www.researchgate.net/profile/Barry-Ir-win/publication/327622948_FPGA_Based_Implementation_of_a_High_Perfor-mance_Scalable_NetFlow_Filter/links/5b9a17a192851c4ba8181ba5/FPGA-Based-Implementation-of-a-High-Performance-Scalable-NetFlow-Filter.pdf
- Description: Full packet analysis on firewalls and intrusion detection, although effec-tive, has been found in recent times to be detrimental to the overall per-formance of networks that receive large volumes of throughput. For this reason partial packet analysis algorithms such as the NetFlow protocol have emerged to better mitigate these bottlenecks. This research delves into implementing a hardware accelerated, scalable, high per-formance system for NetFlow analysis and attack mitigation. Further-more, this implementation takes on attack mitigation through collection and processing of network flows produced at the source, rather than at the site of incident. This research platform manages to scale out its back-end through dis-tributed analysis over multiple hosts using the ZeroMQ toolset. Fur-thermore, ZeroMQ allows for multiple NetFlow data publishers, so that plug-ins can subscribe to the publishers that contain the relevant data to further increase the overall performance of the system. The dedicat-ed custom hardware optimizes the received network flows through cleaning, summarization and re-ordering into an easy to pass form when given to the sequential component of the system; this being the back-end.
- Full Text:
- Date Issued: 2015
Free space in the academy
- Authors: Janz, Bruce B
- Date: 2015
- Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/848 , vital:19996
- Description: “Academic freedom” does not mean the same thing to everyone. There are, to be sure, a few who argue against it. Sandra Korn, in the Harvard Crimson last year, argued that we should abandon academic freedom in favor of academic justice. She argues that we have reached a consensus on issues such as racism, classism and sexism, and so to promote racist or classist or sexist views under the guise of “academic freedom” is to ignore a higher standard and more importantly to ignore the fact that academic freedom is always couched in political realities, and is never the dispassionate exercise of reason and the pursuit of knowledge. It always serves an agenda, and so if that is the case, it should serve the agenda of justice, particularly justice for disadvantaged and marginalized people. Her online article, when I last looked, had almost 1300 comments, and had inspired commentary from a number of other publications. You can imagine the range of these comments and reactions: everything from “this is long overdue” to the newest favorite insult circulating the internet, “she’s just another Social Justice Warrior (SJW).”
- Full Text:
- Date Issued: 2015
- Authors: Janz, Bruce B
- Date: 2015
- Subjects: Academic Freedom -- South Africa Universities and colleges -- South Africa Equality Liberty Education and state -- South Africa Education, Higher -- South Africa
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/848 , vital:19996
- Description: “Academic freedom” does not mean the same thing to everyone. There are, to be sure, a few who argue against it. Sandra Korn, in the Harvard Crimson last year, argued that we should abandon academic freedom in favor of academic justice. She argues that we have reached a consensus on issues such as racism, classism and sexism, and so to promote racist or classist or sexist views under the guise of “academic freedom” is to ignore a higher standard and more importantly to ignore the fact that academic freedom is always couched in political realities, and is never the dispassionate exercise of reason and the pursuit of knowledge. It always serves an agenda, and so if that is the case, it should serve the agenda of justice, particularly justice for disadvantaged and marginalized people. Her online article, when I last looked, had almost 1300 comments, and had inspired commentary from a number of other publications. You can imagine the range of these comments and reactions: everything from “this is long overdue” to the newest favorite insult circulating the internet, “she’s just another Social Justice Warrior (SJW).”
- Full Text:
- Date Issued: 2015
From linguistic determinism to technological determinism
- Kaschula, Russell H, Mostert, André M
- Authors: Kaschula, Russell H , Mostert, André M
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67062 , vital:29027 , https://doi.org/10.4018/978-1-4666-5888-2.ch447
- Description: publisher version , From Introduction: This article seeks to analyse the link between linguistic determinism, the notion that language determines our thought and the way we perceive our reality, as espoused by the Sapir-Whorf hypothesis, and contemporary technological determinism. Arguably this link takes place within a global context where equal access to technology is not yet guaranteed. Ellul (1964) and Lawson’s (2004) observations create an interesting metaphor in terms of the technological beast staring down human society. The overwhelming response if we accept Lawson’s observation is complacency at best or downright naivety at worst regarding the impact of technology on our thinking. Lawson made his observation in the pre-Facebook era and subsequent literature is now much more focused on all aspects of technology within our contemporary milieu. Technology is now totally ubiquitous in the developed world and becoming more so in developing countries, albeit with a much stronger mobile bias for early technology adopters. That technology is rushing ahead of many individuals and institutions is almost an aphorism with many lagging in its wake. This lag as recognised by Brynjolfson and McAfree (2011) has wide social and economic implications for all members of society, in the case of business those that do not keep up go under. A further pertinent question revolves around how individuals who start from low technological literacy levels or do not keep pace with technological developments are impacted. Dlutu (2013) assesses for example the impact of social network sites on the isiXhosa language and culture in both a rural and urban area of South Africa. Furthermore one may then ask how this technological milieu impacts on the general aspects of the day to day lives and thinking of all members of a society. This gives rise to the concept of technological determinism which in its simplest form states ‘that technology has important effects on our lives’ (Adler, 2008, p. 537). This is far too simplistic when the contemporaneous technological developments are assessed. Adler (2008, p. 537) goes further and recognizes ‘that technology itself is socially determined…and social structures co-evolve in a non-deterministic, emergent process…the effects of any given technology depend mainly on how it is implemented which in turn is socially determined’ (Adler, 2008, p. 537). Engaging this socially determined application of technology can be advanced when the relationship with language and language determinism is considered. Moreover, it is the interplay between technology and language that gives rise to the emerging concept of a language singularity which is brought about by a form of technological determinism. This article seeks to explore the possible effects of rapid technological development on human interaction, language and culture in a ‘globalized’ world which has unequal access to literacy and technology. Furthermore, the article explores the link between language, culture, thought and technology and the type of linguistic and technological determinism that we can anticipate.
- Full Text: false
- Date Issued: 2015
- Authors: Kaschula, Russell H , Mostert, André M
- Date: 2015
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/67062 , vital:29027 , https://doi.org/10.4018/978-1-4666-5888-2.ch447
- Description: publisher version , From Introduction: This article seeks to analyse the link between linguistic determinism, the notion that language determines our thought and the way we perceive our reality, as espoused by the Sapir-Whorf hypothesis, and contemporary technological determinism. Arguably this link takes place within a global context where equal access to technology is not yet guaranteed. Ellul (1964) and Lawson’s (2004) observations create an interesting metaphor in terms of the technological beast staring down human society. The overwhelming response if we accept Lawson’s observation is complacency at best or downright naivety at worst regarding the impact of technology on our thinking. Lawson made his observation in the pre-Facebook era and subsequent literature is now much more focused on all aspects of technology within our contemporary milieu. Technology is now totally ubiquitous in the developed world and becoming more so in developing countries, albeit with a much stronger mobile bias for early technology adopters. That technology is rushing ahead of many individuals and institutions is almost an aphorism with many lagging in its wake. This lag as recognised by Brynjolfson and McAfree (2011) has wide social and economic implications for all members of society, in the case of business those that do not keep up go under. A further pertinent question revolves around how individuals who start from low technological literacy levels or do not keep pace with technological developments are impacted. Dlutu (2013) assesses for example the impact of social network sites on the isiXhosa language and culture in both a rural and urban area of South Africa. Furthermore one may then ask how this technological milieu impacts on the general aspects of the day to day lives and thinking of all members of a society. This gives rise to the concept of technological determinism which in its simplest form states ‘that technology has important effects on our lives’ (Adler, 2008, p. 537). This is far too simplistic when the contemporaneous technological developments are assessed. Adler (2008, p. 537) goes further and recognizes ‘that technology itself is socially determined…and social structures co-evolve in a non-deterministic, emergent process…the effects of any given technology depend mainly on how it is implemented which in turn is socially determined’ (Adler, 2008, p. 537). Engaging this socially determined application of technology can be advanced when the relationship with language and language determinism is considered. Moreover, it is the interplay between technology and language that gives rise to the emerging concept of a language singularity which is brought about by a form of technological determinism. This article seeks to explore the possible effects of rapid technological development on human interaction, language and culture in a ‘globalized’ world which has unequal access to literacy and technology. Furthermore, the article explores the link between language, culture, thought and technology and the type of linguistic and technological determinism that we can anticipate.
- Full Text: false
- Date Issued: 2015
Gay men and fatherhood in South Africa: a discursive study
- Morison, Tracy, Lynch, Ingrid, Reddy, Vasu
- Authors: Morison, Tracy , Lynch, Ingrid , Reddy, Vasu
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143782 , vital:38282 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: There is little South African research on gender and sexual minorities’ reproductive decision-making and, to date, no published work explicitly focused on gay men. Motivated by the virtual absence of gay men in research, as well as their marginalisation more generally, we undertook a qualitative investigation of gay men’s thoughts, feelings and perspectives of fatherhood, fatherhood decisions, and experiences of pathways to parenthood. Framed by a reproductive justice perspective, the aim of the study was not only to generate new knowledge, but also to inform policy, services, and advocacy. In this paper we present some of the findings from our discursive analysis of participants’ accounts of their own experiences of the pathway to parenthood or remaining ‘childfree’. We locate our analysis within the broader South African context and show how the entanglement of various social identity markers - particularly gender, race, and class - come to bear on participants’ experiences.
- Full Text:
- Date Issued: 2015
- Authors: Morison, Tracy , Lynch, Ingrid , Reddy, Vasu
- Date: 2015
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143782 , vital:38282 , https://ischp.files.wordpress.com/2015/08/ischp_2015_abstract_booklet.pdf
- Description: There is little South African research on gender and sexual minorities’ reproductive decision-making and, to date, no published work explicitly focused on gay men. Motivated by the virtual absence of gay men in research, as well as their marginalisation more generally, we undertook a qualitative investigation of gay men’s thoughts, feelings and perspectives of fatherhood, fatherhood decisions, and experiences of pathways to parenthood. Framed by a reproductive justice perspective, the aim of the study was not only to generate new knowledge, but also to inform policy, services, and advocacy. In this paper we present some of the findings from our discursive analysis of participants’ accounts of their own experiences of the pathway to parenthood or remaining ‘childfree’. We locate our analysis within the broader South African context and show how the entanglement of various social identity markers - particularly gender, race, and class - come to bear on participants’ experiences.
- Full Text:
- Date Issued: 2015
Genetic and biological characterisation of a novel Plutella xylostella granulovirus, PlxyGV-SA
- Abdulkadir, Fatima, Knox, Caroline M, Marsberg, Tamryn, Hill, Martin P, Moore, Sean D
- Authors: Abdulkadir, Fatima , Knox, Caroline M , Marsberg, Tamryn , Hill, Martin P , Moore, Sean D
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417971 , vital:71498 , xlink:href="https://doi.org/10.1007/s10526-015-9666-3"
- Description: Plutella xylostella granulovirus (PlxyGV) has been isolated from insect populations in many countries and is considered a potential biopesticide for sustainable control of P. xylostella (L.) (Lepidoptera: Plutellidae). Several PlxyGV isolates have been genetically characterised, and the full genome sequence of PlxyGV-Japan is available for comparison with novel isolates. A South African PlxyGV was recently recovered from an overcrowded laboratory P. xylostella colony and identified as a genetically distinct isolate by sequencing of the granulin gene and restriction endonuclease (REN) analysis of genomic DNA. In this report, PlxyGV-SA was further characterised by PCR amplification and sequencing of egt, lef-8 and lef-9 genes, and several amino acid substitutions were observed. The PstI REN profile of PlxyGV-SA was different from that of PlxyGV-Japan in terms of band size and number, thereby confirming its novel genetic identity. Surface dose bioassays showed that PlxyGV-SA is pathogenic to neonate but not late instar larvae at the same and higher virus doses, indicating that a biopesticide should be targeted at early larval stages in the field.
- Full Text:
- Date Issued: 2015
- Authors: Abdulkadir, Fatima , Knox, Caroline M , Marsberg, Tamryn , Hill, Martin P , Moore, Sean D
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/417971 , vital:71498 , xlink:href="https://doi.org/10.1007/s10526-015-9666-3"
- Description: Plutella xylostella granulovirus (PlxyGV) has been isolated from insect populations in many countries and is considered a potential biopesticide for sustainable control of P. xylostella (L.) (Lepidoptera: Plutellidae). Several PlxyGV isolates have been genetically characterised, and the full genome sequence of PlxyGV-Japan is available for comparison with novel isolates. A South African PlxyGV was recently recovered from an overcrowded laboratory P. xylostella colony and identified as a genetically distinct isolate by sequencing of the granulin gene and restriction endonuclease (REN) analysis of genomic DNA. In this report, PlxyGV-SA was further characterised by PCR amplification and sequencing of egt, lef-8 and lef-9 genes, and several amino acid substitutions were observed. The PstI REN profile of PlxyGV-SA was different from that of PlxyGV-Japan in terms of band size and number, thereby confirming its novel genetic identity. Surface dose bioassays showed that PlxyGV-SA is pathogenic to neonate but not late instar larvae at the same and higher virus doses, indicating that a biopesticide should be targeted at early larval stages in the field.
- Full Text:
- Date Issued: 2015
Global Cicada Sound Collection I: Recordings from South Africa and Malawi by BW Price and MH Villet and harvesting of BioAcoustica data by GBIF
- Baker, Ed, Price, Benjamin W, Rycroft, Simon, Villet, Martin H
- Authors: Baker, Ed , Price, Benjamin W , Rycroft, Simon , Villet, Martin H
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441420 , vital:73886 , https://bdj.pensoft.net/articles.php?id=5792
- Description: Sound collections for singing insects provide important repositories that underpin existing research (eg Price et al. 2007 at http://bio. acousti. ca/node/11801; Price et al. 2010) and make bioacoustic collections available for future work, including insect communication (Ordish 1992), systematics (eg David et al. 2003), and automated identification (Bennett et al. 2015). The BioAcoustica platform (Baker et al. 2015) is both a repository and analysis platform for bioacoustic collections: allowing collections to be available in perpetuity, and also facilitating complex analyses using the BioVeL cloud infrastructure (Vicario et al. 2011). The Global Cicada Sound Collection is a project to make recordings of the world's cicadas (Hemiptera: Cicadidae) available using open licences to maximise their potential for study and reuse. This first component of the Global Cicada Sound Collection comprises recordings made between 2006 and 2008 of Cicadidae in South Africa and Malawi.
- Full Text:
- Date Issued: 2015
- Authors: Baker, Ed , Price, Benjamin W , Rycroft, Simon , Villet, Martin H
- Date: 2015
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/441420 , vital:73886 , https://bdj.pensoft.net/articles.php?id=5792
- Description: Sound collections for singing insects provide important repositories that underpin existing research (eg Price et al. 2007 at http://bio. acousti. ca/node/11801; Price et al. 2010) and make bioacoustic collections available for future work, including insect communication (Ordish 1992), systematics (eg David et al. 2003), and automated identification (Bennett et al. 2015). The BioAcoustica platform (Baker et al. 2015) is both a repository and analysis platform for bioacoustic collections: allowing collections to be available in perpetuity, and also facilitating complex analyses using the BioVeL cloud infrastructure (Vicario et al. 2011). The Global Cicada Sound Collection is a project to make recordings of the world's cicadas (Hemiptera: Cicadidae) available using open licences to maximise their potential for study and reuse. This first component of the Global Cicada Sound Collection comprises recordings made between 2006 and 2008 of Cicadidae in South Africa and Malawi.
- Full Text:
- Date Issued: 2015