A moderate elevation in [CO 2] results in potential hypervirulence on SABBIErica
- Gallagher, Sean, Hill, Jaclyn M, Murugan, N, Botha, Christiaan E J
- Authors: Gallagher, Sean , Hill, Jaclyn M , Murugan, N , Botha, Christiaan E J
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68835 , vital:29329 , https://doi.org/10.1016/j.sajb.2017.10.010
- Description: The Russian Wheat Aphid (Diuraphis noxia Kurdjumov, 1913) (RWA) is a serious pest of grain crops and is of considerable concern in South Africa, particularly in terms of barley grown specifically for the brewing industry. This paper highlights the effect of a small (50 ppm) increase in [CO2] on the growth rate of the four South African RWA biotypes on the SABBIErica barley cultivar. Controlled environment experiments revealed that the colony growth rate for RWASA4 was significantly lower than SA1 under ambient conditions as well as significantly lower than SA1, SA2 or SA3 under elevated CO2 conditions. The unexpected difference suggested an atypical, non-preferential feeding habit on SABBIErica, for RWASA4. The small RWASA4 colonies inflicted similar morphological damage to the significantly larger RWASA1 – RWASA3 biotype populations — indicative of potential hypervirulence under elevated CO2. The continuous feeding of RWASA biotypes causes damage to the transport system as well as substantial, catastrophic damage to mesophyll chloroplasts as well as mitochondria within the host plant's leaves. The TEM study revealed evidence of sequential/systematic degeneration of chloroplasts and mitochondria with continued aphid feeding, which we suggest is an indication of potential emergent hypervirulence under elevated CO2 conditions.
- Full Text: false
- Date Issued: 2017
- Authors: Gallagher, Sean , Hill, Jaclyn M , Murugan, N , Botha, Christiaan E J
- Date: 2017
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/68835 , vital:29329 , https://doi.org/10.1016/j.sajb.2017.10.010
- Description: The Russian Wheat Aphid (Diuraphis noxia Kurdjumov, 1913) (RWA) is a serious pest of grain crops and is of considerable concern in South Africa, particularly in terms of barley grown specifically for the brewing industry. This paper highlights the effect of a small (50 ppm) increase in [CO2] on the growth rate of the four South African RWA biotypes on the SABBIErica barley cultivar. Controlled environment experiments revealed that the colony growth rate for RWASA4 was significantly lower than SA1 under ambient conditions as well as significantly lower than SA1, SA2 or SA3 under elevated CO2 conditions. The unexpected difference suggested an atypical, non-preferential feeding habit on SABBIErica, for RWASA4. The small RWASA4 colonies inflicted similar morphological damage to the significantly larger RWASA1 – RWASA3 biotype populations — indicative of potential hypervirulence under elevated CO2. The continuous feeding of RWASA biotypes causes damage to the transport system as well as substantial, catastrophic damage to mesophyll chloroplasts as well as mitochondria within the host plant's leaves. The TEM study revealed evidence of sequential/systematic degeneration of chloroplasts and mitochondria with continued aphid feeding, which we suggest is an indication of potential emergent hypervirulence under elevated CO2 conditions.
- Full Text: false
- Date Issued: 2017
Arsenic in the boardroom: strategies to deal with toxic leaders
- Authors: Mey, Michelle
- Subjects: Bullying in the workplace , Psychology, Industrial
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/10948/20945 , vital:29421
- Description: Effective leaders are critical in building successful organisations, communities and nations. Whilst academia and business alike advocate positive organisational psychology and the development of positive leadership, the sad reality is that there is a growing global prevalence of toxic leadership, with research indicating that between 20% and 60% of leaders may be defined as toxic (Veldsman, 2016). While toxic leaders, who initially come across as charming, confident and persuasive, may be effective in achieving organisational objectives in the short term, the long-term consequences can be devastating to the organisational brand and reputation, as well as to the morale and psyche of its members. Even though toxic leaders and bullies are becoming increasingly prevalent in organisations there is a lack of empirical research on workplace bullying.
- Full Text:
- Authors: Mey, Michelle
- Subjects: Bullying in the workplace , Psychology, Industrial
- Language: English
- Type: text , Lectures
- Identifier: http://hdl.handle.net/10948/20945 , vital:29421
- Description: Effective leaders are critical in building successful organisations, communities and nations. Whilst academia and business alike advocate positive organisational psychology and the development of positive leadership, the sad reality is that there is a growing global prevalence of toxic leadership, with research indicating that between 20% and 60% of leaders may be defined as toxic (Veldsman, 2016). While toxic leaders, who initially come across as charming, confident and persuasive, may be effective in achieving organisational objectives in the short term, the long-term consequences can be devastating to the organisational brand and reputation, as well as to the morale and psyche of its members. Even though toxic leaders and bullies are becoming increasingly prevalent in organisations there is a lack of empirical research on workplace bullying.
- Full Text:
Strangers “at home”: gay, lesbian and bisexual students’ strategies for resisting heteronormativity in university residence life
- Authors: Munyuki, C , Vincent, Louise
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141680 , vital:37996 , DOI: 10.20853/32-3-2521
- Description: Higher education in post-apartheid South Africa has been concerned with the establishment of non-discriminatory institutions. However, research continues to highlight various experiences of exclusionary practices across universities in South Africa. In this article, we demonstrate the various coping mechanisms that some students who self-identify as gay, lesbian or bisexual in the university residences adopt to deal with the exclusionary practices that the dominant heteronormative culture of the institution (re)produces which positions them as “sexual strangers” within the institutional “home”. We adopt Vangelisti and Crumley’s (1998) three categories of behaviour namely “acquiescence” which we term here as endeavours to “fit in”, “invulnerability” which we identify as “keeping one’s distance”, “verbal active” as “voicing” and a fourth category we identify as “turning the tables on heteronormativity” in our discussion. We also highlight the various forms of responses that the institution adopts in its attempts to create a conducive environment for all.
- Full Text:
- Date Issued: 2018
- Authors: Munyuki, C , Vincent, Louise
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/141680 , vital:37996 , DOI: 10.20853/32-3-2521
- Description: Higher education in post-apartheid South Africa has been concerned with the establishment of non-discriminatory institutions. However, research continues to highlight various experiences of exclusionary practices across universities in South Africa. In this article, we demonstrate the various coping mechanisms that some students who self-identify as gay, lesbian or bisexual in the university residences adopt to deal with the exclusionary practices that the dominant heteronormative culture of the institution (re)produces which positions them as “sexual strangers” within the institutional “home”. We adopt Vangelisti and Crumley’s (1998) three categories of behaviour namely “acquiescence” which we term here as endeavours to “fit in”, “invulnerability” which we identify as “keeping one’s distance”, “verbal active” as “voicing” and a fourth category we identify as “turning the tables on heteronormativity” in our discussion. We also highlight the various forms of responses that the institution adopts in its attempts to create a conducive environment for all.
- Full Text:
- Date Issued: 2018
Unraveling the Motions behind Enterovirus 71 Uncoating:
- Ross, Caroline J, Atilgan, Ali R, Tastan Bishop, Özlem, Atilgan, Canan
- Authors: Ross, Caroline J , Atilgan, Ali R , Tastan Bishop, Özlem , Atilgan, Canan
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148158 , vital:38715 , DOI: 10.1016/j.bpj.2017.12.021
- Description: Enterovirus 71 can be a severe pathogen in small children and immunocompromised adults. Virus uncoating is a critical step in the infection of the host cell; however, the mechanisms that control this process remain poorly understood. We applied normal mode analysis and perturbation response scanning to several complexes of the virus capsid and present a coarse-graining approach to analyze the full capsid. We show that our method offers an alternative to expressing the system as a set of rigid blocks and accounts for the interconnection between nodes within each subunit and protein interfaces across the capsid. In our coarse-grained approach, the modes associated with capsid expansion are captured in the first three nondegenerate modes and correspond to the changes observed in structural studies of the virus. We show that the resolution of the analysis may be modified without losing information on the global motions leading to uncoating.
- Full Text:
- Date Issued: 2018
- Authors: Ross, Caroline J , Atilgan, Ali R , Tastan Bishop, Özlem , Atilgan, Canan
- Date: 2018
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/148158 , vital:38715 , DOI: 10.1016/j.bpj.2017.12.021
- Description: Enterovirus 71 can be a severe pathogen in small children and immunocompromised adults. Virus uncoating is a critical step in the infection of the host cell; however, the mechanisms that control this process remain poorly understood. We applied normal mode analysis and perturbation response scanning to several complexes of the virus capsid and present a coarse-graining approach to analyze the full capsid. We show that our method offers an alternative to expressing the system as a set of rigid blocks and accounts for the interconnection between nodes within each subunit and protein interfaces across the capsid. In our coarse-grained approach, the modes associated with capsid expansion are captured in the first three nondegenerate modes and correspond to the changes observed in structural studies of the virus. We show that the resolution of the analysis may be modified without losing information on the global motions leading to uncoating.
- Full Text:
- Date Issued: 2018
‘Yummy or crummy?': the multisensory components of medicines-taking among HIV-positive youth
- Hodes, Rebecca, Vale, Beth, Toska, Elona, Cluver, Lucie, Dowse, Roslind, Ashorn, Mikael
- Authors: Hodes, Rebecca , Vale, Beth , Toska, Elona , Cluver, Lucie , Dowse, Roslind , Ashorn, Mikael
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156663 , vital:40036 , DOI: 10.1080/17441692.2018.1504103
- Description: The global rollout of Antiretroviral Treatment (ART) has revealed an urgent need to understand the medicines-taking practices of HIV-positive adolescents. In the last decade, the literature on the social determinants of health has broadened the evidence-base on ART adherence. Interdisciplinary studies have expanded conceptions of medicines-taking beyond clinical or health systems frameworks, recognising the importance of socio-structural conditions and of patients’ beliefs and experiences. Participatory research techniques which foreground the perspectives of adolescents provide greater insights still into their adherence. This article explores the use of participatory methods within a broader study on the social determinants of ART adherence among HIV-positive adolescents in South Africa. We describe how participatory methods were incorporated into this study (n = 1,059 in the quantitative baseline). We focus on an exercise, ‘Yummy or crummy?’, that explored the multisensory dimensions of medicines-taking, including their colour, smell, shape, and delivery mechanism. We describe two principal findings: first, adolescents’ preference for greater understanding of the chemical workings of medicines, manifested in their preferences for colour, taste and shape of medicines; and second, the vital relationship between sensory preferences and the social imperatives of discretion and confidentiality regarding HIV-status.
- Full Text:
- Date Issued: 2019
- Authors: Hodes, Rebecca , Vale, Beth , Toska, Elona , Cluver, Lucie , Dowse, Roslind , Ashorn, Mikael
- Date: 2019
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156663 , vital:40036 , DOI: 10.1080/17441692.2018.1504103
- Description: The global rollout of Antiretroviral Treatment (ART) has revealed an urgent need to understand the medicines-taking practices of HIV-positive adolescents. In the last decade, the literature on the social determinants of health has broadened the evidence-base on ART adherence. Interdisciplinary studies have expanded conceptions of medicines-taking beyond clinical or health systems frameworks, recognising the importance of socio-structural conditions and of patients’ beliefs and experiences. Participatory research techniques which foreground the perspectives of adolescents provide greater insights still into their adherence. This article explores the use of participatory methods within a broader study on the social determinants of ART adherence among HIV-positive adolescents in South Africa. We describe how participatory methods were incorporated into this study (n = 1,059 in the quantitative baseline). We focus on an exercise, ‘Yummy or crummy?’, that explored the multisensory dimensions of medicines-taking, including their colour, smell, shape, and delivery mechanism. We describe two principal findings: first, adolescents’ preference for greater understanding of the chemical workings of medicines, manifested in their preferences for colour, taste and shape of medicines; and second, the vital relationship between sensory preferences and the social imperatives of discretion and confidentiality regarding HIV-status.
- Full Text:
- Date Issued: 2019
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