The gold of one’s ring is not far more precious than the gold of one’s heart: Reported life satisfaction among married and cohabitating South African adults
- Botha, Ferdi, Booysen, Frikkie
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396181 , vital:69156 , xlink:href=" https://doi.org/10.1007/s10902-012-9337-3"
- Description: This paper tests for differences in reported life satisfaction between married and cohabiting persons, i.e. the cohabitation gap, and in particular whether selection factors can explain the cohabitation gap. The paper also explores whether age at marriage and at start of cohabitation as well as the duration of relationship type matters for subjective well-being. Based on statistical and regression analysis of the 2008 National Income Dynamics Survey, married and cohabiting persons exhibit some differences in their respective determinants of life satisfaction. While the age at relationship commencement has no relationship with well-being, there is evidence to suggest that married people become more satisfied at a later stage in marriage, while cohabitants are more satisfied initially. A significant cohabitation gap exists (0.251), but after controlling for various selection factors, the cohabitation gap virtually disappears (0.042) and becomes insignificant, which suggests that marriage and cohabitation are very similar in South Africa. Relative income, absolute income, and education explain the largest part of the cohabitation gap. Against the global backdrop of an increasing trend towards cohabitation and declining marriage rates, the overall results of this paper suggest that, since a cohabitation gap no longer exists after controlling for selection factors, South Africans may as well not go the “official route” of entering into marriage, as cohabitation provides similar benefits in terms of its contribution to individual satisfaction with life.
- Full Text:
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396181 , vital:69156 , xlink:href=" https://doi.org/10.1007/s10902-012-9337-3"
- Description: This paper tests for differences in reported life satisfaction between married and cohabiting persons, i.e. the cohabitation gap, and in particular whether selection factors can explain the cohabitation gap. The paper also explores whether age at marriage and at start of cohabitation as well as the duration of relationship type matters for subjective well-being. Based on statistical and regression analysis of the 2008 National Income Dynamics Survey, married and cohabiting persons exhibit some differences in their respective determinants of life satisfaction. While the age at relationship commencement has no relationship with well-being, there is evidence to suggest that married people become more satisfied at a later stage in marriage, while cohabitants are more satisfied initially. A significant cohabitation gap exists (0.251), but after controlling for various selection factors, the cohabitation gap virtually disappears (0.042) and becomes insignificant, which suggests that marriage and cohabitation are very similar in South Africa. Relative income, absolute income, and education explain the largest part of the cohabitation gap. Against the global backdrop of an increasing trend towards cohabitation and declining marriage rates, the overall results of this paper suggest that, since a cohabitation gap no longer exists after controlling for selection factors, South Africans may as well not go the “official route” of entering into marriage, as cohabitation provides similar benefits in terms of its contribution to individual satisfaction with life.
- Full Text:
Does national sporting performance affect stock market returns in South Africa?
- Authors: Botha, Ferdi , De Beer, Carl
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396023 , vital:69144 , xlink:href="https://hdl.handle.net/10520/EJC135922"
- Description: This study explores whether South African national sporting performance can influence investors in such a way that it has the ability to impact on market returns. Using standard event study methodology, this study determines the constant mean return using the daily All-Share price index on the JSE for the period of 1 January 1990 to 31 December 2010. This study focuses on three of South Africa's most popular sports, namely soccer, cricket and rugby, and examines if these three sports have the ability to influence market returns. Although there is some evidence of a relationship between stock returns and sporting performance in the descriptive analysis, the regression results indicate that sporting performance in South Africa does not significantly explain abnormal market returns on the JSE. The study provides a number of possible reasons for this finding and concludes by suggesting areas for future research.
- Full Text:
- Authors: Botha, Ferdi , De Beer, Carl
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396023 , vital:69144 , xlink:href="https://hdl.handle.net/10520/EJC135922"
- Description: This study explores whether South African national sporting performance can influence investors in such a way that it has the ability to impact on market returns. Using standard event study methodology, this study determines the constant mean return using the daily All-Share price index on the JSE for the period of 1 January 1990 to 31 December 2010. This study focuses on three of South Africa's most popular sports, namely soccer, cricket and rugby, and examines if these three sports have the ability to influence market returns. Although there is some evidence of a relationship between stock returns and sporting performance in the descriptive analysis, the regression results indicate that sporting performance in South Africa does not significantly explain abnormal market returns on the JSE. The study provides a number of possible reasons for this finding and concludes by suggesting areas for future research.
- Full Text:
The relationship between marital status and life satisfaction among South African adults
- Botha, Ferdi, Booysen, Frikkie
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396207 , vital:69158 , xlink:href="https://hdl.handle.net/10520/EJC138900"
- Description: This article examines the association between marital status and reported life satisfaction in South Africa. Using the 2008 National Income Dynamics Survey, the relationship between marital status and life satisfaction is heterogeneous. In the overall sample, life satisfaction is significantly higher for married compared to widowed individuals, while the former are more satisfied than those from all other marital statuses. In the overall and female samples, married people are more satisfied compared to those from all other marital status groups. Married men are not significantly more satisfied than men from other marital statuses as a whole. Marriage is positively associated with life satisfaction among women, but not among men.
- Full Text:
- Authors: Botha, Ferdi , Booysen, Frikkie
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396207 , vital:69158 , xlink:href="https://hdl.handle.net/10520/EJC138900"
- Description: This article examines the association between marital status and reported life satisfaction in South Africa. Using the 2008 National Income Dynamics Survey, the relationship between marital status and life satisfaction is heterogeneous. In the overall sample, life satisfaction is significantly higher for married compared to widowed individuals, while the former are more satisfied than those from all other marital statuses. In the overall and female samples, married people are more satisfied compared to those from all other marital status groups. Married men are not significantly more satisfied than men from other marital statuses as a whole. Marriage is positively associated with life satisfaction among women, but not among men.
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Stock returns and Friday the 13th effect in five African countries
- Authors: Botha, Ferdi
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396127 , vital:69152 , xlink:href="https://www.ajol.info/index.php/aref/article/view/91060"
- Description: This study is concerned with Friday the 13th and daily stock market returns in five African countries. Using the MSCI Global Equity Indices during various periods, the evidence overwhelmingly suggests that there is no Friday the 13th effect.
- Full Text:
- Authors: Botha, Ferdi
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/396127 , vital:69152 , xlink:href="https://www.ajol.info/index.php/aref/article/view/91060"
- Description: This study is concerned with Friday the 13th and daily stock market returns in five African countries. Using the MSCI Global Equity Indices during various periods, the evidence overwhelmingly suggests that there is no Friday the 13th effect.
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Nutrient-mediated effects on Cornops aquaticum Brüner (Orthoptera: Acrididae), a potential biological control agent of water hyacinth, Eichhornia crassipes (Mart.) Solms (Pontederiaceae)
- Bownes, Angela, Hill, Martin P, Byrne, Marcus J
- Authors: Bownes, Angela , Hill, Martin P , Byrne, Marcus J
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406131 , vital:70241 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.07.023"
- Description: Environmental nutrient availability can drive and modify both plant responses to herbivory by phytophagous insects and insect feeding patterns which, in insect-weed systems, may ultimately determine whether biological control succeeds or fails. The impacts of insect biological control agents on the invasive aquatic weed, water hyacinth (Eichhornia crassipes) vary with nutrient levels in the environment. It was therefore considered important to evaluate nutrient-specific responses of E. crassipes to a grasshopper herbivore, Cornops aquaticum, prior to its release in South Africa. Both plant productivity and the response of E. crassipes to herbivory by C. aquaticum were nutrient dependent. Increases in plant biomass and leaf and ramet production were correlated with increases in nutrients in the water and plant biomass accumulation was reduced by herbivory at all three nutrient levels tested (high = 67%; medium = 100%; low = 400%). C. aquaticum nymphs fed E. crassipes leaves with the lowest nitrogen levels produced the highest biomass of frass during their development, indicating compensatory consumption. The results suggest that environmental nutrient availability will influence efficacy of C. aquaticum. They also provide further evidence that E. crassipes problems are exacerbated by an over-abundance of nutrients in aquatic environments, and that biological control would be a highly effective management tool if aquatic systems in South Africa were less polluted. Additionally, the results also show how an understanding of the fundamental responses of E. crassipes and its insect biocontrol agents to their environment can assist in determining specific management strategies or interventions according to prevailing site-specific conditions.
- Full Text:
- Authors: Bownes, Angela , Hill, Martin P , Byrne, Marcus J
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/406131 , vital:70241 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.07.023"
- Description: Environmental nutrient availability can drive and modify both plant responses to herbivory by phytophagous insects and insect feeding patterns which, in insect-weed systems, may ultimately determine whether biological control succeeds or fails. The impacts of insect biological control agents on the invasive aquatic weed, water hyacinth (Eichhornia crassipes) vary with nutrient levels in the environment. It was therefore considered important to evaluate nutrient-specific responses of E. crassipes to a grasshopper herbivore, Cornops aquaticum, prior to its release in South Africa. Both plant productivity and the response of E. crassipes to herbivory by C. aquaticum were nutrient dependent. Increases in plant biomass and leaf and ramet production were correlated with increases in nutrients in the water and plant biomass accumulation was reduced by herbivory at all three nutrient levels tested (high = 67%; medium = 100%; low = 400%). C. aquaticum nymphs fed E. crassipes leaves with the lowest nitrogen levels produced the highest biomass of frass during their development, indicating compensatory consumption. The results suggest that environmental nutrient availability will influence efficacy of C. aquaticum. They also provide further evidence that E. crassipes problems are exacerbated by an over-abundance of nutrients in aquatic environments, and that biological control would be a highly effective management tool if aquatic systems in South Africa were less polluted. Additionally, the results also show how an understanding of the fundamental responses of E. crassipes and its insect biocontrol agents to their environment can assist in determining specific management strategies or interventions according to prevailing site-specific conditions.
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Third order nonlinear optical properties of phthalocyanines in the presence nanomaterials and in polymer thin films
- Britton, Jonathan, Durmus, Mahmut, Khene, Samson M, Chauke, Vongani, Nyokong, Tebello
- Authors: Britton, Jonathan , Durmus, Mahmut , Khene, Samson M , Chauke, Vongani , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241772 , vital:50968 , xlink:href="https://doi.org/10.1142/S108842461350003X"
- Description: Third order nonlinear optical properties were determined for phthalocyanine complexes 1–10 containing In, Ga and Zn central metals and tetra- or octa-substituted with benzyloxyphenoxy, phenoxy, tert-butylphenoxy and amino groups at peripheral or non-peripheral positions. The phthalocyanines were embedded in poly (methyl methacrylate) polymer in the presence of CdTe quantum dots. All complexes 1–10 were studied in the presence of CdTe quantum dots and embedded in poly (methyl methacrylate) to form thin films. Complex 3 tetrasubstituted with tert-butylphenoxy groups at non-peripheral positions was also studied in the presence of CdS, CdSe quantum dots, fullerenes, single walled carbon nanotubes. Third order nonlinear optical parameters generally increase for Pcs in the presence of CdTe quantum dots.
- Full Text:
- Authors: Britton, Jonathan , Durmus, Mahmut , Khene, Samson M , Chauke, Vongani , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241772 , vital:50968 , xlink:href="https://doi.org/10.1142/S108842461350003X"
- Description: Third order nonlinear optical properties were determined for phthalocyanine complexes 1–10 containing In, Ga and Zn central metals and tetra- or octa-substituted with benzyloxyphenoxy, phenoxy, tert-butylphenoxy and amino groups at peripheral or non-peripheral positions. The phthalocyanines were embedded in poly (methyl methacrylate) polymer in the presence of CdTe quantum dots. All complexes 1–10 were studied in the presence of CdTe quantum dots and embedded in poly (methyl methacrylate) to form thin films. Complex 3 tetrasubstituted with tert-butylphenoxy groups at non-peripheral positions was also studied in the presence of CdS, CdSe quantum dots, fullerenes, single walled carbon nanotubes. Third order nonlinear optical parameters generally increase for Pcs in the presence of CdTe quantum dots.
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Synthesis and nonlinear optical examination of 3 (4), 15 (16)-Bis-(4-tert-butyl-phenoxy)-10, 22-diaminohemiporphyrazinato chloroindium
- Britton, Jonathan, Antunes, Edith M, Nyokong, Tebello
- Authors: Britton, Jonathan , Antunes, Edith M , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241739 , vital:50965 , xlink:href="https://doi.org/10.1016/j.molstruc.2013.05.001"
- Description: 3(4),15(16)-Bis-(4-tert-butyl-phenoxy)-10,22-diaminohemiporphyrazinato chloroindium hemiporphyrazine was synthesized from 1,3,5-triaminobenzene and 4-tert-butyl-phenoxyisoindoline. The structure of the complex was confirmed using mass, nuclear magnetic resonance and infrared spectroscopies. The nonlinear parameters of the compound was also analyzed in dimethylformamide and found to be significantly greater than previously analyzed phthalocyanines.
- Full Text:
- Authors: Britton, Jonathan , Antunes, Edith M , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241739 , vital:50965 , xlink:href="https://doi.org/10.1016/j.molstruc.2013.05.001"
- Description: 3(4),15(16)-Bis-(4-tert-butyl-phenoxy)-10,22-diaminohemiporphyrazinato chloroindium hemiporphyrazine was synthesized from 1,3,5-triaminobenzene and 4-tert-butyl-phenoxyisoindoline. The structure of the complex was confirmed using mass, nuclear magnetic resonance and infrared spectroscopies. The nonlinear parameters of the compound was also analyzed in dimethylformamide and found to be significantly greater than previously analyzed phthalocyanines.
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Optical limiting analysis of phthalocyanines in polymer thin films
- Britton, Jonathan, Litwinski, Christian, Antunes, Edith M, Durmus, Mahmut, Chaukea, Vongani, Nyokong, Tebello
- Authors: Britton, Jonathan , Litwinski, Christian , Antunes, Edith M , Durmus, Mahmut , Chaukea, Vongani , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232488 , vital:49996 , xlink:href="https://doi.org/10.1080/10601325.2013.736269"
- Description: This paper reports on the effect of embedding twelve phthalocyanines containing In, Ga, Zn and Al as central metals in polymer thin films on their optical limiting abilities. This paper also examines the effect of forming a covalent link between zinc tetraamino phthalocyanine (10) and poly (methyl acrylic acid) (PMAA), and Zn (11) or OHAl (12) octacarboxy phthalocyanines with polyethylenimine (PEI). The average film thickness (for phthalocyanines mixed or linked to polymers) of each Pc/Polymer films on glass was 95 μm. The hyperpolarizability of the twelve phthalocyanines was found to be in the range of 10−26 to 10−24 esu.L. This is significantly higher than the hyperpolarizabilities of these phthalocyanines in solution, which ranged from 10−30 to 10−26 esu.L. Degradation studies seem to indicate that placing a phthalocyanine within a polymer thin film may protect it slightly from photo- and thermal degradation.
- Full Text:
- Authors: Britton, Jonathan , Litwinski, Christian , Antunes, Edith M , Durmus, Mahmut , Chaukea, Vongani , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/232488 , vital:49996 , xlink:href="https://doi.org/10.1080/10601325.2013.736269"
- Description: This paper reports on the effect of embedding twelve phthalocyanines containing In, Ga, Zn and Al as central metals in polymer thin films on their optical limiting abilities. This paper also examines the effect of forming a covalent link between zinc tetraamino phthalocyanine (10) and poly (methyl acrylic acid) (PMAA), and Zn (11) or OHAl (12) octacarboxy phthalocyanines with polyethylenimine (PEI). The average film thickness (for phthalocyanines mixed or linked to polymers) of each Pc/Polymer films on glass was 95 μm. The hyperpolarizability of the twelve phthalocyanines was found to be in the range of 10−26 to 10−24 esu.L. This is significantly higher than the hyperpolarizabilities of these phthalocyanines in solution, which ranged from 10−30 to 10−26 esu.L. Degradation studies seem to indicate that placing a phthalocyanine within a polymer thin film may protect it slightly from photo- and thermal degradation.
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Poly methyl methacrylate films containing metallophthalocyanines in the presence of CdTe quantum dots
- Britton, Jonathan, Durmus, Mahmut, Chauke, Vongani, Nyokong, Tebello
- Authors: Britton, Jonathan , Durmus, Mahmut , Chauke, Vongani , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241629 , vital:50956 , xlink:href="https://doi.org/10.1016/j.molstruc.2013.09.017"
- Description: Non-linear optical (NLO) parameters were determined for phthalocyanine complexes containing In, Ga and Zn as central metals when embedded in poly (methyl methacrylate) polymer in the absence and presence of quantum dots (QDs) in an effort to create the most optimal optical limiting material. The QDs employed were CdTe–TGA (TGA = thioglylcolic acid). Triplet lifetimes generally increased as the value of the ratio of absorption cross sections of the excited state to that of the ground state (k) decreased on addition of CdTe–TGA to the phthalocyanines. The saturation energy density (Fsat) values were generally smaller in the films when compared to the solutions. Fsat, Ilim, Im[χ(3)]/α and γ all gave values which were of optimal range (i.e. the Im[χ(3)]/α and γ values were high enough to ensure adequate optical limiting but not too high to make the compounds behave like optical filters. Also, the Fsat and Ilim values were small enough to mean that the optical limiting process started at an intensity which was not too high) for complex 10 containing Zn central metal and tetrasubstituted with amino groups.
- Full Text:
- Authors: Britton, Jonathan , Durmus, Mahmut , Chauke, Vongani , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/241629 , vital:50956 , xlink:href="https://doi.org/10.1016/j.molstruc.2013.09.017"
- Description: Non-linear optical (NLO) parameters were determined for phthalocyanine complexes containing In, Ga and Zn as central metals when embedded in poly (methyl methacrylate) polymer in the absence and presence of quantum dots (QDs) in an effort to create the most optimal optical limiting material. The QDs employed were CdTe–TGA (TGA = thioglylcolic acid). Triplet lifetimes generally increased as the value of the ratio of absorption cross sections of the excited state to that of the ground state (k) decreased on addition of CdTe–TGA to the phthalocyanines. The saturation energy density (Fsat) values were generally smaller in the films when compared to the solutions. Fsat, Ilim, Im[χ(3)]/α and γ all gave values which were of optimal range (i.e. the Im[χ(3)]/α and γ values were high enough to ensure adequate optical limiting but not too high to make the compounds behave like optical filters. Also, the Fsat and Ilim values were small enough to mean that the optical limiting process started at an intensity which was not too high) for complex 10 containing Zn central metal and tetrasubstituted with amino groups.
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Halogenated oxindole and indoles from the South African marine ascidian Distaplia skoogi:
- Bromley, Candice L, Parker-Nance, Shirley, de la Mare, Jo-Anne, Edkins, Adrienne L, Beukes, Denzil R, Davies-Coleman, Michael T
- Authors: Bromley, Candice L , Parker-Nance, Shirley , de la Mare, Jo-Anne , Edkins, Adrienne L , Beukes, Denzil R , Davies-Coleman, Michael T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164918 , vital:41184
- Description: The known 3,6-dibromoindole (1), 6-bromo-3-chloroindole (2) and 6-bromo-2-oxindole (3) were isolated from the marine ascidian (sea squirt) Distapia skoogi collected from Algoa Bay, South Africa. Standard spectroscopic techniques were used to elucidate the structures of 1-3. All three compounds were found to be moderately cytotoxic to metastatic MDA-MB-231 breast cancer cells.
- Full Text:
- Authors: Bromley, Candice L , Parker-Nance, Shirley , de la Mare, Jo-Anne , Edkins, Adrienne L , Beukes, Denzil R , Davies-Coleman, Michael T
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/164918 , vital:41184
- Description: The known 3,6-dibromoindole (1), 6-bromo-3-chloroindole (2) and 6-bromo-2-oxindole (3) were isolated from the marine ascidian (sea squirt) Distapia skoogi collected from Algoa Bay, South Africa. Standard spectroscopic techniques were used to elucidate the structures of 1-3. All three compounds were found to be moderately cytotoxic to metastatic MDA-MB-231 breast cancer cells.
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Engineering Education Research for educational change: the possibilities of critical realism for conceptualising causal mechanicsms in education
- Case, Jennifer, Blackie, Margaret A
- Authors: Case, Jennifer , Blackie, Margaret A
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426637 , vital:72374 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.07.023"
- Description: Engineering Education Research (EER) grew in prominence from the late 1990s as purposes for this field were espoused in relation to the necessity of change for engineering education in the newly globalising world. Arguments centred on overall challenges with recruitment to engineering, specifically in relation to historically underrepresented populations, as well as with the forms of education (both in terms of quality of teaching and relevance of curricula) offered to students, and the needs of employers as reflected in newly-emerged global accreditation systems. In a field that is at least partly directed towards educational change, there is a need to understand how change typically happens in education systems. This article first draws on findings from the sociology of education to show that causality in relation to educational change is complex. It then turns to the philosophy of critical realism for a way of thinking about change that can inform EER, and concludes by outlining how this might change the research questions that drive the field, and how these might be approached.
- Full Text:
- Authors: Case, Jennifer , Blackie, Margaret A
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/426637 , vital:72374 , xlink:href="https://doi.org/10.1016/j.biocontrol.2013.07.023"
- Description: Engineering Education Research (EER) grew in prominence from the late 1990s as purposes for this field were espoused in relation to the necessity of change for engineering education in the newly globalising world. Arguments centred on overall challenges with recruitment to engineering, specifically in relation to historically underrepresented populations, as well as with the forms of education (both in terms of quality of teaching and relevance of curricula) offered to students, and the needs of employers as reflected in newly-emerged global accreditation systems. In a field that is at least partly directed towards educational change, there is a need to understand how change typically happens in education systems. This article first draws on findings from the sociology of education to show that causality in relation to educational change is complex. It then turns to the philosophy of critical realism for a way of thinking about change that can inform EER, and concludes by outlining how this might change the research questions that drive the field, and how these might be approached.
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Voices of the hungry: a qualitative measure of household food access and food insecurity in South Africa
- Chakona, Gamuchirai, Shackleton, Charlie M
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67277 , vital:29066 , https://doi.org/10.1186/s40066-017-0149-x
- Description: publisher version , Background: South Africa is rated a food secure nation, but large numbers of households within the country have inadequate access to nutrient-rich diverse foods. The study sought to investigate households’ physical and economic access and availability of food, in relation to local context which influences households’ access to and ability to grow food which may affect the dietary quality. We sought to understand self-reported healthy diets, food insecurity from the perspective of people who experienced it, barriers to household food security and perceptions and feelings on food access as well as strategies households use to cope with food shortages and their perceptions on improving household food security. Methods: Focus group discussions were conducted along a rural–urban continuum in three South African towns situated along an agro-ecological gradient. Participants were asked about their knowledge of healthy diets, factors influencing their food consumption, their perceptions regarding food insecurity, barriers to food security, coping strategies and solutions to improve access to nutrient-rich foods. Results: A total of 91 people participated in 11 focus groups, with 76% females. The majority of participants aged between 31 and 50 years. Participants were knowledgeable about healthy diets but had limited access to it hence consumed monotonous diets. The perceptions provided insights into the pressing issues of inadequate access to food, food insecurity, coping strategies and ideas on improving food security. The majority of participants reported on experiencing food insecurity and female-headed households, unemployed and orphaned children were most vulnerable. Focus group participants highlighted the complexity of the food system in their communities which relies on own production, collecting from open spaces, donations and to a larger extent purchase, in the context of unemployment, low income, water and land shortages as well as theft. Conclusion: The results provide a significant contribution from a needs assessment perspective from the communities, identify “hidden” constrains in household food access and provide effective future solutions for improving food security in the communities. Government should assist with capacity building, employment creation and providing resources (especially, land and water) for communities to practise agriculture which they all agreed can improve food security.
- Full Text:
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67277 , vital:29066 , https://doi.org/10.1186/s40066-017-0149-x
- Description: publisher version , Background: South Africa is rated a food secure nation, but large numbers of households within the country have inadequate access to nutrient-rich diverse foods. The study sought to investigate households’ physical and economic access and availability of food, in relation to local context which influences households’ access to and ability to grow food which may affect the dietary quality. We sought to understand self-reported healthy diets, food insecurity from the perspective of people who experienced it, barriers to household food security and perceptions and feelings on food access as well as strategies households use to cope with food shortages and their perceptions on improving household food security. Methods: Focus group discussions were conducted along a rural–urban continuum in three South African towns situated along an agro-ecological gradient. Participants were asked about their knowledge of healthy diets, factors influencing their food consumption, their perceptions regarding food insecurity, barriers to food security, coping strategies and solutions to improve access to nutrient-rich foods. Results: A total of 91 people participated in 11 focus groups, with 76% females. The majority of participants aged between 31 and 50 years. Participants were knowledgeable about healthy diets but had limited access to it hence consumed monotonous diets. The perceptions provided insights into the pressing issues of inadequate access to food, food insecurity, coping strategies and ideas on improving food security. The majority of participants reported on experiencing food insecurity and female-headed households, unemployed and orphaned children were most vulnerable. Focus group participants highlighted the complexity of the food system in their communities which relies on own production, collecting from open spaces, donations and to a larger extent purchase, in the context of unemployment, low income, water and land shortages as well as theft. Conclusion: The results provide a significant contribution from a needs assessment perspective from the communities, identify “hidden” constrains in household food access and provide effective future solutions for improving food security in the communities. Government should assist with capacity building, employment creation and providing resources (especially, land and water) for communities to practise agriculture which they all agreed can improve food security.
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Local setting influences the quantity of household food waste in mid-sized South African towns
- Chakona, Gamuchirai, Shackleton, Charlie M
- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67289 , vital:29067 , https://doi.org/10.1371/journal.pone.0189407
- Description: publisher version , From Introduction: The world faces a food security challenge with approximately 868 million people undernourished and about two billion people suffering from the negative health consequences of micronutrient deficiencies [1]. Yet, at least one-third of food produced for human consumption is lost or wasted along the food chain between farm and fork [2–7]. Food waste refers to wholesome edible material intended for human consumption, arising at any point in the food supply chain that is instead discarded, lost, degraded or consumed by pests [8]. Food loss is defined as the decrease in food quantity or quality which makes it unfit for human consumption [9]. According to the European Commission [10], food waste is composed of raw or cooked food materials such as vegetable peelings, meat trimmings and spoiled or excess ingredients or prepared food as well as bones, carcasses and organs. However, food waste can be measured only for edible products that are directed to human consumption [6]. Food losses take place at production, postharvest and processing stages in the food supply chain and the food losses that occur at the end of the food chain (retail and final consumption) are called “food waste” [11]. In our study food waste refers to food losses that occur at the end of the food chain (final consumption at household or consumer level) which include edible products that are directed to human consumption and are discarded when not consumed for various reasons. It is related to consumers’ behaviour [6,11] and it includes food loss before, during or after meal preparation in the household. , The research was funded by VW foundation under the Livelihoods Urbanisation and Natural Resources in Africa (LUNA) project through Freiburg University, Germany. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of this manuscript
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- Authors: Chakona, Gamuchirai , Shackleton, Charlie M
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/67289 , vital:29067 , https://doi.org/10.1371/journal.pone.0189407
- Description: publisher version , From Introduction: The world faces a food security challenge with approximately 868 million people undernourished and about two billion people suffering from the negative health consequences of micronutrient deficiencies [1]. Yet, at least one-third of food produced for human consumption is lost or wasted along the food chain between farm and fork [2–7]. Food waste refers to wholesome edible material intended for human consumption, arising at any point in the food supply chain that is instead discarded, lost, degraded or consumed by pests [8]. Food loss is defined as the decrease in food quantity or quality which makes it unfit for human consumption [9]. According to the European Commission [10], food waste is composed of raw or cooked food materials such as vegetable peelings, meat trimmings and spoiled or excess ingredients or prepared food as well as bones, carcasses and organs. However, food waste can be measured only for edible products that are directed to human consumption [6]. Food losses take place at production, postharvest and processing stages in the food supply chain and the food losses that occur at the end of the food chain (retail and final consumption) are called “food waste” [11]. In our study food waste refers to food losses that occur at the end of the food chain (final consumption at household or consumer level) which include edible products that are directed to human consumption and are discarded when not consumed for various reasons. It is related to consumers’ behaviour [6,11] and it includes food loss before, during or after meal preparation in the household. , The research was funded by VW foundation under the Livelihoods Urbanisation and Natural Resources in Africa (LUNA) project through Freiburg University, Germany. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of this manuscript
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A capability approach: Its potential for transformative education research focusing on education for sustainable development and gender issues in science teacher education
- Authors: Chikunda, Charles
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387120 , vital:68208 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122266"
- Description: In this article, I use the capability approach to explore the role that the science, mathematics and technical subjects (SMTs) teacher education curriculum can play as a ‘gender conversion factor’. This comes amidst evidence that a major hindrance to the participation of girls in these disciplines is a lack of gender responsiveness in the pedagogy applied in schools. Seven teacher educators, who were purposively sampled at a Technical Teachers’ College in Zimbabwe, were the research participants. I adopted a case study design in which I used in-depth interviews, focus-group discussions and document analysis to generate data. Data was analysed deductively using predetermined themes based on an analytical tool anchored on Sen’s two, but quite distinct, aspects of freedom, that is, the opportunity aspect and the process aspect of freedom. The findings reveal that there is a limited awareness of gender issues among teacher educators, and that these issues are not being transformed into curriculum practice. All in all, it is evident that curriculum practices of SMTs teacher educators are riddled with gender blindness and so trainee teachers graduate from college without the necessary agency to deal with personal, social and environmental conversion factors that can play a role in girls converting the curriculum into functionings (beings and doings) and wider freedoms and valued beings and doings (capabilities).
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- Authors: Chikunda, Charles
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/387120 , vital:68208 , xlink:href="https://www.ajol.info/index.php/sajee/article/view/122266"
- Description: In this article, I use the capability approach to explore the role that the science, mathematics and technical subjects (SMTs) teacher education curriculum can play as a ‘gender conversion factor’. This comes amidst evidence that a major hindrance to the participation of girls in these disciplines is a lack of gender responsiveness in the pedagogy applied in schools. Seven teacher educators, who were purposively sampled at a Technical Teachers’ College in Zimbabwe, were the research participants. I adopted a case study design in which I used in-depth interviews, focus-group discussions and document analysis to generate data. Data was analysed deductively using predetermined themes based on an analytical tool anchored on Sen’s two, but quite distinct, aspects of freedom, that is, the opportunity aspect and the process aspect of freedom. The findings reveal that there is a limited awareness of gender issues among teacher educators, and that these issues are not being transformed into curriculum practice. All in all, it is evident that curriculum practices of SMTs teacher educators are riddled with gender blindness and so trainee teachers graduate from college without the necessary agency to deal with personal, social and environmental conversion factors that can play a role in girls converting the curriculum into functionings (beings and doings) and wider freedoms and valued beings and doings (capabilities).
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X-ray photoelectron spectroscopy analysis of the effect of alkyl-and arylthio substituents on manganese phthalocyanines for self-assembled monolayer formation on gold
- Coates, Megan, Nyokong, Tebello
- Authors: Coates, Megan , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190490 , vital:44999 , xlink:href="https://doi.org/10.1016/j.elecom.2013.03.019"
- Description: Self-assembled monolayers of an octa-substituted alkylthio and arylthio manganese phthalocyanines were formed on gold. X-ray photoelectron spectroscopy was used to analyse both of the phthalocyanine layers on gold. Approximately 60% of the sulphur groups in the aryl substituted-SAM surface were bound to gold through the cleavage of the C S bond, as opposed to only 37% for the alkyl substituted-SAM.
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- Authors: Coates, Megan , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/190490 , vital:44999 , xlink:href="https://doi.org/10.1016/j.elecom.2013.03.019"
- Description: Self-assembled monolayers of an octa-substituted alkylthio and arylthio manganese phthalocyanines were formed on gold. X-ray photoelectron spectroscopy was used to analyse both of the phthalocyanine layers on gold. Approximately 60% of the sulphur groups in the aryl substituted-SAM surface were bound to gold through the cleavage of the C S bond, as opposed to only 37% for the alkyl substituted-SAM.
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Characterization of glassy carbon electrodes modified with carbon nanotubes and iron phthalocyanine through grafting and click chemistry
- Coates, Megan, Nyokong, Tebello
- Authors: Coates, Megan , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193746 , vital:45392 , xlink:href="https://doi.org/10.1016/j.electacta.2012.12.112"
- Description: A glassy carbon electrode was modified by adsorption of single-walled carbon nanotubes, followed by electrochemical grafting of 4-azidobenzenediazonium salt, which was in turn reacted with ethynylpyridine through the Sharpless “click chemistry” reaction. Thereafter, iron phthalocyanine was attached to the electrode through axial ligation to the pyridine group. The modified electrode was characterised using X-ray photoelectron spectroscopy and scanning electrochemical microscopy, and well as electrochemistry. The electrocatalytic ability of the modified electrode was tested using hydrazine as a sample analyte, and showed a significant 10-fold improvement in the detection of hydrazine compared to the surface without nanotubes, and comparable stability. The linear range for this surface was over 1.0 × 10−5 to 1.0 × 10−4 mol dm−3, with a limit of detection of 1.10 ± 0.06 μmol dm−3 and sensitivity of 15.61 μA mM−1.
- Full Text:
- Authors: Coates, Megan , Nyokong, Tebello
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/193746 , vital:45392 , xlink:href="https://doi.org/10.1016/j.electacta.2012.12.112"
- Description: A glassy carbon electrode was modified by adsorption of single-walled carbon nanotubes, followed by electrochemical grafting of 4-azidobenzenediazonium salt, which was in turn reacted with ethynylpyridine through the Sharpless “click chemistry” reaction. Thereafter, iron phthalocyanine was attached to the electrode through axial ligation to the pyridine group. The modified electrode was characterised using X-ray photoelectron spectroscopy and scanning electrochemical microscopy, and well as electrochemistry. The electrocatalytic ability of the modified electrode was tested using hydrazine as a sample analyte, and showed a significant 10-fold improvement in the detection of hydrazine compared to the surface without nanotubes, and comparable stability. The linear range for this surface was over 1.0 × 10−5 to 1.0 × 10−4 mol dm−3, with a limit of detection of 1.10 ± 0.06 μmol dm−3 and sensitivity of 15.61 μA mM−1.
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Inkcubeko Nendalo: a bio-cultural diversity schools education project in South Africa and its implications for inclusive Indigenous Knowledge Systems (IKS) Sustainability.
- Cocks, Michelle L, Alexander, Jamie K, Dold, Anthony P
- Authors: Cocks, Michelle L , Alexander, Jamie K , Dold, Anthony P
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141187 , vital:37951 , DOI: 10.1177/0973408212475232
- Description: South Africa is currently the world’s third most biodiverse country, with one of the highest concentrations of threatened biodiversity in the world. Emerging research reveals the increasing pressure on this biodiversity with many wild resources continuing to be utilised for livelihood purposes even within urban environments. The Rio conventions, particularly the CBD, call for an integrated approach to conservation that incorporates local environmental knowledge and practices. In a bid to market itself as globally competitive, South Africa’s Curriculum 2005 (C 2005) is primarily focused on Western-based scientific knowledge, which sidelines the contribution of indigenous knowledge systems (IKS) and ignores the holistic nature of indigenous worldviews. The Inkcubeko Nendalo programme is designed to revitalise cultural identity, showing children the value of local indigenous knowledge and cultural environmental values.
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- Authors: Cocks, Michelle L , Alexander, Jamie K , Dold, Anthony P
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141187 , vital:37951 , DOI: 10.1177/0973408212475232
- Description: South Africa is currently the world’s third most biodiverse country, with one of the highest concentrations of threatened biodiversity in the world. Emerging research reveals the increasing pressure on this biodiversity with many wild resources continuing to be utilised for livelihood purposes even within urban environments. The Rio conventions, particularly the CBD, call for an integrated approach to conservation that incorporates local environmental knowledge and practices. In a bid to market itself as globally competitive, South Africa’s Curriculum 2005 (C 2005) is primarily focused on Western-based scientific knowledge, which sidelines the contribution of indigenous knowledge systems (IKS) and ignores the holistic nature of indigenous worldviews. The Inkcubeko Nendalo programme is designed to revitalise cultural identity, showing children the value of local indigenous knowledge and cultural environmental values.
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Rhino poaching: supply and demand uncertain
- Collins, Alan, Fraser, Gavin, Snowball, Jeanette D
- Authors: Collins, Alan , Fraser, Gavin , Snowball, Jeanette D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70476 , vital:29665 , https://doi.org/10.1126/science.340.6137.1167-a
- Description: IN THEIR POLICY FORUM “LEGAL TRADE OF AFRICA’S RHINO HORNS” (1 MARCH, P. 1038), D. Biggs et al. point out that the trade ban on rhino horn has not been successful in reducing rhino poaching, which reached a record high of 668 in 2012. They argue that trade bans support illegal organizations, whereas a regulated legal market could reduce poaching effort and provide much-needed income for conservation. In making their case, Biggs et al. overlook a few important points.
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- Authors: Collins, Alan , Fraser, Gavin , Snowball, Jeanette D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70476 , vital:29665 , https://doi.org/10.1126/science.340.6137.1167-a
- Description: IN THEIR POLICY FORUM “LEGAL TRADE OF AFRICA’S RHINO HORNS” (1 MARCH, P. 1038), D. Biggs et al. point out that the trade ban on rhino horn has not been successful in reducing rhino poaching, which reached a record high of 668 in 2012. They argue that trade bans support illegal organizations, whereas a regulated legal market could reduce poaching effort and provide much-needed income for conservation. In making their case, Biggs et al. overlook a few important points.
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Could a regulated market approach for rhinoceros horns work in South Africa? Some practical issues and concerns
- Collins, Alan, Fraser, Gavin C G, Snowball, Jeanette D
- Authors: Collins, Alan , Fraser, Gavin C G , Snowball, Jeanette D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68600 , vital:29292 , http://www.essa2013.org.za/fullpaper/essa2013_2708.pdf
- Description: Publisher version , One of the proposals for fighting rhinoceros poaching is to legalise the trade in rhino horn and adopt a regulated market approach (RMA), which would require a vote at the 2016 CITES meeting in order to overturn the ban on the trade in rhino horn. The legal trade in rhino horn would enable the auctioning of stockpiles of horn and encourage captive breeding programmes. The aim of increasing the supply of horn is to reduce incentives to poach by driving down the price. This paper uses a conceptual/theoretical approach to consider the practical implications of the adoption of an RMA, drawing on demand, supply and production theory. The intention is explicitly to set out some practical concerns and issues that seem to have been underplayed or neglected in most published economic discourse on the subject. To secure a stockpile for some species needs biological success in captive breeding programs (CBPs) but this varies across species and habitats. Rhinoceros herds in a CBP would need relatively spatially extensive terrain and costly permanent security measures, and only appear feasible for the less aggressive “white” rhino. Thus, market price would actually need to be sustained at a high level to cover the start-up and security costs of such a programme that are unlikely to fall significantly. This is a double-edged sword in that the persistent high price of rhino horn provides an incentive for continued poaching activities. Supplementary policy measures that differentiate among consumer groups may also prove necessary.
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- Authors: Collins, Alan , Fraser, Gavin C G , Snowball, Jeanette D
- Date: 2013
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68600 , vital:29292 , http://www.essa2013.org.za/fullpaper/essa2013_2708.pdf
- Description: Publisher version , One of the proposals for fighting rhinoceros poaching is to legalise the trade in rhino horn and adopt a regulated market approach (RMA), which would require a vote at the 2016 CITES meeting in order to overturn the ban on the trade in rhino horn. The legal trade in rhino horn would enable the auctioning of stockpiles of horn and encourage captive breeding programmes. The aim of increasing the supply of horn is to reduce incentives to poach by driving down the price. This paper uses a conceptual/theoretical approach to consider the practical implications of the adoption of an RMA, drawing on demand, supply and production theory. The intention is explicitly to set out some practical concerns and issues that seem to have been underplayed or neglected in most published economic discourse on the subject. To secure a stockpile for some species needs biological success in captive breeding programs (CBPs) but this varies across species and habitats. Rhinoceros herds in a CBP would need relatively spatially extensive terrain and costly permanent security measures, and only appear feasible for the less aggressive “white” rhino. Thus, market price would actually need to be sustained at a high level to cover the start-up and security costs of such a programme that are unlikely to fall significantly. This is a double-edged sword in that the persistent high price of rhino horn provides an incentive for continued poaching activities. Supplementary policy measures that differentiate among consumer groups may also prove necessary.
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Persistence and virulence of promising entomopathogenic fungal isolates for use in citrus orchards in South Africa
- Coombes, Candice A, Hill, Martin P, Moore, Sean D, Dames, Joanna F, Fullard, T
- Authors: Coombes, Candice A , Hill, Martin P , Moore, Sean D , Dames, Joanna F , Fullard, T
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416893 , vital:71394 , xlink:href="https://doi.org/10.1080/09583157.2013.819489"
- Description: Thaumatotibia leucotreta (Meyrick) (1912) (Lepidoptera: Tortricidae) is a key economic pest of citrus in South Africa. Although a variety of control options are available, none currently registered target the soil-dwelling life stages of the pest. Three fungal isolates, two Metarhizium anisopliae sensu lato Metschnikoff (Sorokin) isolates (G 11 3 L6 and FCM Ar 23 B3) and one Beauveria bassiana sensu lato Balsamo (Vuillemin) isolate (G Ar 17 B3) have been identified as showing the greatest potential against T. leucotreta soil-dwelling life stages. Since environmental persistence is an important factor in the success of entomopathogenic fungi against soil pests, the isolates, along with two commercial isolates (B. bassiana Eco-Bb® and M. anisopliae ICIPE 69), were subjected to a six-month field persistence trial. Every month after burial of the fungal isolates, inside net bags, in orchard soil, the number of colony forming units (CFUs) per gram of soil was measured and the viability of the conidia was assessed using bioassays. All isolates investigated were capable of persisting in the soil for the duration of the trial period and in addition, were capable of initiating infection in T. leucotreta late fifth instar larvae and subsequent pupae. However, with the exception of the commercial isolates which showed some correlation, no correlation was found between the number of CFUs recorded and percentage T. leucotreta mycosis. Persistence of entomopathogenic fungi in the field is affected by a series of factors, and although the effect of these factors was not measured, the data have provided preliminary evidence towards the persistence capability of these candidate biopesticides against T. leucotreta.
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- Authors: Coombes, Candice A , Hill, Martin P , Moore, Sean D , Dames, Joanna F , Fullard, T
- Date: 2013
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/416893 , vital:71394 , xlink:href="https://doi.org/10.1080/09583157.2013.819489"
- Description: Thaumatotibia leucotreta (Meyrick) (1912) (Lepidoptera: Tortricidae) is a key economic pest of citrus in South Africa. Although a variety of control options are available, none currently registered target the soil-dwelling life stages of the pest. Three fungal isolates, two Metarhizium anisopliae sensu lato Metschnikoff (Sorokin) isolates (G 11 3 L6 and FCM Ar 23 B3) and one Beauveria bassiana sensu lato Balsamo (Vuillemin) isolate (G Ar 17 B3) have been identified as showing the greatest potential against T. leucotreta soil-dwelling life stages. Since environmental persistence is an important factor in the success of entomopathogenic fungi against soil pests, the isolates, along with two commercial isolates (B. bassiana Eco-Bb® and M. anisopliae ICIPE 69), were subjected to a six-month field persistence trial. Every month after burial of the fungal isolates, inside net bags, in orchard soil, the number of colony forming units (CFUs) per gram of soil was measured and the viability of the conidia was assessed using bioassays. All isolates investigated were capable of persisting in the soil for the duration of the trial period and in addition, were capable of initiating infection in T. leucotreta late fifth instar larvae and subsequent pupae. However, with the exception of the commercial isolates which showed some correlation, no correlation was found between the number of CFUs recorded and percentage T. leucotreta mycosis. Persistence of entomopathogenic fungi in the field is affected by a series of factors, and although the effect of these factors was not measured, the data have provided preliminary evidence towards the persistence capability of these candidate biopesticides against T. leucotreta.
- Full Text: