Love thy neighbour : group properties of gaping behaviour in mussel aggregations
- Nicastro, Katy R, Zardi, Gerardo I, McQuaid, Christopher D, Pearson, Gareth A, Serrão, Ester A
- Authors: Nicastro, Katy R , Zardi, Gerardo I , McQuaid, Christopher D , Pearson, Gareth A , Serrão, Ester A
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6841 , http://hdl.handle.net/10962/d1010991
- Description: By associating closely with others to form a group, an animal can benefit from a number of advantages including reduced risk of predation, amelioration of environmental conditions, and increased reproductive success, but at the price of reduced resources. Although made up of individual members, an aggregation often displays novel effects that do not manifest at the level of the individual organism. Here we show that very simple behaviour in intertidal mussels shows new effects in dense aggregations but not in isolated individuals. Perna perna and Mytilus galloprovincialis are gaping (periodic valve movement during emersion) and non-gaping mussels respectively. P. perna gaping behaviour had no effect on body temperatures of isolated individuals, while it led to increased humidity and decreased temperatures in dense groups (beds). Gaping resulted in cooler body temperatures for P. perna than M. galloprovincialis when in aggregations, while solitary individuals exhibited the highest temperatures. Gradients of increasing body temperature were detected from the center to edges of beds, but M. galloprovincialis at the edge had the same temperature as isolated individuals. Furthermore, a field study showed that during periods of severe heat stress, mortality rates of mussels within beds of the gaping P. perna were lower than those of isolated individuals or within beds of M. galloprovincialis, highlighting the determinant role of gaping on fitness and group functioning. We demonstrate that new effects of very simple individual behaviour lead to amelioration of abiotic conditions at the aggregation level and that these effects increase mussel resistance to thermal stress.
- Full Text:
- Date Issued: 2012
- Authors: Nicastro, Katy R , Zardi, Gerardo I , McQuaid, Christopher D , Pearson, Gareth A , Serrão, Ester A
- Date: 2012
- Language: English
- Type: Article
- Identifier: vital:6841 , http://hdl.handle.net/10962/d1010991
- Description: By associating closely with others to form a group, an animal can benefit from a number of advantages including reduced risk of predation, amelioration of environmental conditions, and increased reproductive success, but at the price of reduced resources. Although made up of individual members, an aggregation often displays novel effects that do not manifest at the level of the individual organism. Here we show that very simple behaviour in intertidal mussels shows new effects in dense aggregations but not in isolated individuals. Perna perna and Mytilus galloprovincialis are gaping (periodic valve movement during emersion) and non-gaping mussels respectively. P. perna gaping behaviour had no effect on body temperatures of isolated individuals, while it led to increased humidity and decreased temperatures in dense groups (beds). Gaping resulted in cooler body temperatures for P. perna than M. galloprovincialis when in aggregations, while solitary individuals exhibited the highest temperatures. Gradients of increasing body temperature were detected from the center to edges of beds, but M. galloprovincialis at the edge had the same temperature as isolated individuals. Furthermore, a field study showed that during periods of severe heat stress, mortality rates of mussels within beds of the gaping P. perna were lower than those of isolated individuals or within beds of M. galloprovincialis, highlighting the determinant role of gaping on fitness and group functioning. We demonstrate that new effects of very simple individual behaviour lead to amelioration of abiotic conditions at the aggregation level and that these effects increase mussel resistance to thermal stress.
- Full Text:
- Date Issued: 2012
Rhodes University Library Annual Report 2011 : acting Library Director’s Review
- Authors: Berger, Jeanne
- Date: 2012
- Language: English
- Type: Text
- Identifier: vital:7944 , http://hdl.handle.net/10962/d1011891
- Description: [From the Introduction] 2011 saw the consolidation of a number of changes to Library services implemented in 2010 as a result of the 2009 Review of the Library Services Division. These include: 1) Collection development operating as a collaborative effort between Library staff and the academic community. The Collection Development Policy also underwent a major revision and was approved by Senate in October as the “Collection Development and Management Policy and Guidelines”. 2) The Faculty Liaison Service – the librarians in these teams are now proactively liaising with academics, for example, playing a crucial role in collection development for the departments, ensuring that they spend their information resources grants, creating awareness of appropriate online information resources and offering information literacy workshops.
- Full Text:
- Date Issued: 2012
- Authors: Berger, Jeanne
- Date: 2012
- Language: English
- Type: Text
- Identifier: vital:7944 , http://hdl.handle.net/10962/d1011891
- Description: [From the Introduction] 2011 saw the consolidation of a number of changes to Library services implemented in 2010 as a result of the 2009 Review of the Library Services Division. These include: 1) Collection development operating as a collaborative effort between Library staff and the academic community. The Collection Development Policy also underwent a major revision and was approved by Senate in October as the “Collection Development and Management Policy and Guidelines”. 2) The Faculty Liaison Service – the librarians in these teams are now proactively liaising with academics, for example, playing a crucial role in collection development for the departments, ensuring that they spend their information resources grants, creating awareness of appropriate online information resources and offering information literacy workshops.
- Full Text:
- Date Issued: 2012
Welcome Address of the Vice‐Chancellor of Rhodes University, Dr Saleem Badat, to First‐Year students
- Authors: Badat, Saleem
- Date: 2012
- Language: English
- Type: text
- Identifier: vital:7592 , http://hdl.handle.net/10962/d1006583
- Description: From introduction: Our first purpose is to produce knowledge, so that we can better understand our natural and social worlds and also enrich our scientific and cultural heritage. The second purpose of a university is to disseminate knowledge and to develop critical and creative minds. Our goals, yours and ours, must be for you to think imaginatively, ‘effectively and critically;’ to ‘achieve depth in some field of knowledge;’ to appreciate how we ‘gain knowledge and understanding of the universe, of society, and of ourselves;’ to have ‘a broad knowledge of other cultures and other times;’ to critique ideas and views and construct alternatives, and to communicate cogently, orally and in writing. Our final purpose as a university is to undertake community engagement, whether this is as part of academic courses or your voluntary participation in community projects organized by our Community Engagement Office.
- Full Text:
- Date Issued: 2012
Welcome Address of the Vice‐Chancellor of Rhodes University, Dr Saleem Badat, to First‐Year students
- Authors: Badat, Saleem
- Date: 2012
- Language: English
- Type: text
- Identifier: vital:7592 , http://hdl.handle.net/10962/d1006583
- Description: From introduction: Our first purpose is to produce knowledge, so that we can better understand our natural and social worlds and also enrich our scientific and cultural heritage. The second purpose of a university is to disseminate knowledge and to develop critical and creative minds. Our goals, yours and ours, must be for you to think imaginatively, ‘effectively and critically;’ to ‘achieve depth in some field of knowledge;’ to appreciate how we ‘gain knowledge and understanding of the universe, of society, and of ourselves;’ to have ‘a broad knowledge of other cultures and other times;’ to critique ideas and views and construct alternatives, and to communicate cogently, orally and in writing. Our final purpose as a university is to undertake community engagement, whether this is as part of academic courses or your voluntary participation in community projects organized by our Community Engagement Office.
- Full Text:
- Date Issued: 2012
Financial Management: BEC 311
- Authors: Fatoki, O O , Tait, M
- Date: 2012-01
- Subjects: Financial risk management
- Language: English
- Type: Examination paper
- Identifier: vital:17439 , http://hdl.handle.net/10353/d1010250
- Description: Financial Management: BEC 311, Special examination January 2012.
- Full Text: false
- Date Issued: 2012-01
- Authors: Fatoki, O O , Tait, M
- Date: 2012-01
- Subjects: Financial risk management
- Language: English
- Type: Examination paper
- Identifier: vital:17439 , http://hdl.handle.net/10353/d1010250
- Description: Financial Management: BEC 311, Special examination January 2012.
- Full Text: false
- Date Issued: 2012-01
Advanced English Language and General Literature: ECL 310
- Tshotsho, B P, Morkel, N, Blatchford, M, Scott, R, Mndebele, T, Sherzinger, K, Mpepo, V N
- Authors: Tshotsho, B P , Morkel, N , Blatchford, M , Scott, R , Mndebele, T , Sherzinger, K , Mpepo, V N
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:18310 , http://hdl.handle.net/10353/d1011420
- Description: Advanced English Language and General Literature: ECL 310, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
- Authors: Tshotsho, B P , Morkel, N , Blatchford, M , Scott, R , Mndebele, T , Sherzinger, K , Mpepo, V N
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:18310 , http://hdl.handle.net/10353/d1011420
- Description: Advanced English Language and General Literature: ECL 310, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
Advanced English Language and General Literature: ECL 310
- Tshotsho, B P, Morkel, N, Blatchford, M, Scott, R, Mndebele, T, Scherzinger, K, Mpepo, V M
- Authors: Tshotsho, B P , Morkel, N , Blatchford, M , Scott, R , Mndebele, T , Scherzinger, K , Mpepo, V M
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:18309 , http://hdl.handle.net/10353/d1011419
- Description: Advanced English Language and General Literature: ECL 310, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
- Authors: Tshotsho, B P , Morkel, N , Blatchford, M , Scott, R , Mndebele, T , Scherzinger, K , Mpepo, V M
- Date: 2011-06
- Language: English
- Type: Examination paper
- Identifier: vital:18309 , http://hdl.handle.net/10353/d1011419
- Description: Advanced English Language and General Literature: ECL 310, degree examination June 2011.
- Full Text: false
- Date Issued: 2011-06
Age validation, growth, mortality, and demographic modeling of spotted gully shark (Triakis megalopterus) from the southeast coast of South Africa
- Booth, Anthony J, Foulis, Alan J, Smale, Malcolm J
- Authors: Booth, Anthony J , Foulis, Alan J , Smale, Malcolm J
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123630 , vital:35466 , https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/2011/1091/booth.pdf
- Description: This study documents validation of vertebral band-pair formation in spotted gully shark (Triakis megalopterus) with the use of f luorochrome injection and tagging of captive and wild sharks over a 21-year period. Growth and mortality rates of T. megalopterus were also estimated and a demographic analysis of the species was conducted. Of the 23 OTC (oxytetracycline) -marked vertebrae examined (12 from captive and 11 from wild sharks), seven vertebrae (three from captive and four from wild sharks) exhibited chelation of the OTC and f luoresced under ultraviolet light. It was concluded that a single opaque and translucent band pair was deposited annually up to at least 25 years of age, the maximum age recorded. Reader precision was assessed by using an index of average percent error calculated at 5%. No significant differences were found between male and female growth patterns (P>0.05), and von Bertalanffy growth model parameters for combined sexes were estimated to be L∞=1711.07 mm TL, k=0.11/yr and t0= –2.43 yr (n=86). Natural mortality was estimated at 0.17/yr. Age at maturity was estimated at 11 years for males and 15 years for females. Results of the demographic analysis showed that the population, in the absence of fishing mortality, was stable and not significantly different from zero and particularly sensitive to overfishing. At the current age at first capture and natural mortality rate, the fishing mortality rate required to result in negative population growth was low at F>0.004/ yr. Elasticity analysis revealed that juvenile survival was the principal factor in explaining variability in population growth rate.
- Full Text:
- Date Issued: 2011
- Authors: Booth, Anthony J , Foulis, Alan J , Smale, Malcolm J
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123630 , vital:35466 , https://spo.nmfs.noaa.gov/sites/default/files/pdf-content/2011/1091/booth.pdf
- Description: This study documents validation of vertebral band-pair formation in spotted gully shark (Triakis megalopterus) with the use of f luorochrome injection and tagging of captive and wild sharks over a 21-year period. Growth and mortality rates of T. megalopterus were also estimated and a demographic analysis of the species was conducted. Of the 23 OTC (oxytetracycline) -marked vertebrae examined (12 from captive and 11 from wild sharks), seven vertebrae (three from captive and four from wild sharks) exhibited chelation of the OTC and f luoresced under ultraviolet light. It was concluded that a single opaque and translucent band pair was deposited annually up to at least 25 years of age, the maximum age recorded. Reader precision was assessed by using an index of average percent error calculated at 5%. No significant differences were found between male and female growth patterns (P>0.05), and von Bertalanffy growth model parameters for combined sexes were estimated to be L∞=1711.07 mm TL, k=0.11/yr and t0= –2.43 yr (n=86). Natural mortality was estimated at 0.17/yr. Age at maturity was estimated at 11 years for males and 15 years for females. Results of the demographic analysis showed that the population, in the absence of fishing mortality, was stable and not significantly different from zero and particularly sensitive to overfishing. At the current age at first capture and natural mortality rate, the fishing mortality rate required to result in negative population growth was low at F>0.004/ yr. Elasticity analysis revealed that juvenile survival was the principal factor in explaining variability in population growth rate.
- Full Text:
- Date Issued: 2011
Comparative structural bioinformatics analysis of Bacillus amyloliquefaciens chemotaxis proteins within Bacillus subtilis group
- Yssel, Anna, Reva, Oleg, Tastan Bishop, Özlem
- Authors: Yssel, Anna , Reva, Oleg , Tastan Bishop, Özlem
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123966 , vital:35521 , https://doi.10.1007/s00253-011-3582-y
- Description: Chemotaxis is a process in which bacteria sense their chemical environment and move towards more favorable conditions. Since plant colonization by bacteria is a multifaceted process which requires a response to the complex chemical environment, a finely tuned and sensitive chemotaxis system is needed. Members of the Bacillus subtilis group including Bacillus amyloliquefaciens are industrially important, for example, as bio-pesticides. The group exhibits plant growth-promoting characteristics, with different specificity towards certain host plants. Therefore, we hypothesize that while the principal molecular mechanisms of bacterial chemotaxis may be conserved, the bacterial chemotaxis system may need an evolutionary tweaking to adapt it to specific requirements, particularly in the process of evolution of free-living soil organisms, towards plant colonization behaviour. To date, almost nothing is known about what parts of the chemotaxis proteins are subjected to positive amino acid substitutions, involved in adjusting the chemotaxis system of bacteria during speciation. In this novel study, positively selected and purified sites of chemotaxis proteins were calculated, and these residues were mapped onto homology models that were built for the chemotaxis proteins, in an attempt to understand the spatial evolution of the chemotaxis proteins. Various positively selected amino acids were identified in semi-conserved regions of the proteins away from the known active sites.
- Full Text:
- Date Issued: 2011
- Authors: Yssel, Anna , Reva, Oleg , Tastan Bishop, Özlem
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123966 , vital:35521 , https://doi.10.1007/s00253-011-3582-y
- Description: Chemotaxis is a process in which bacteria sense their chemical environment and move towards more favorable conditions. Since plant colonization by bacteria is a multifaceted process which requires a response to the complex chemical environment, a finely tuned and sensitive chemotaxis system is needed. Members of the Bacillus subtilis group including Bacillus amyloliquefaciens are industrially important, for example, as bio-pesticides. The group exhibits plant growth-promoting characteristics, with different specificity towards certain host plants. Therefore, we hypothesize that while the principal molecular mechanisms of bacterial chemotaxis may be conserved, the bacterial chemotaxis system may need an evolutionary tweaking to adapt it to specific requirements, particularly in the process of evolution of free-living soil organisms, towards plant colonization behaviour. To date, almost nothing is known about what parts of the chemotaxis proteins are subjected to positive amino acid substitutions, involved in adjusting the chemotaxis system of bacteria during speciation. In this novel study, positively selected and purified sites of chemotaxis proteins were calculated, and these residues were mapped onto homology models that were built for the chemotaxis proteins, in an attempt to understand the spatial evolution of the chemotaxis proteins. Various positively selected amino acids were identified in semi-conserved regions of the proteins away from the known active sites.
- Full Text:
- Date Issued: 2011
Cultural importance of non-timber forest products: opportunities they pose for bio-cultural diversity in dynamic societies
- Cocks, Michelle L, López, Citlalli, Dold, Anthony P
- Authors: Cocks, Michelle L , López, Citlalli , Dold, Anthony P
- Date: 2011
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/141453 , vital:37973 , ISBN 9783642179822 , DOI: 10.1007/978-3-642-17983-9_5
- Description: There is an increasing awareness that monetary value does not fully represent the complete value and significance of NTFPs. Consequently, there is growing interest in the cultural dimensions of biodiversity and the role that it plays in human well-being. This chapter presents two case studies, one on traditional brooms in South Africa, and the other on amate paper in Mexico, to demonstrate the importance of cultural values on driving demand for NTFPs. Because cultural values are so deeply embedded, the demand for culturally valued NTFPs continue across the rural-urban divide, and are maintained even by modernising urban communities. This poses particular challenges, not only for conservation of the NTFPs, but also to sustain cultural diversity in a rapidly changing world.
- Full Text:
- Date Issued: 2011
- Authors: Cocks, Michelle L , López, Citlalli , Dold, Anthony P
- Date: 2011
- Language: English
- Type: text , book
- Identifier: http://hdl.handle.net/10962/141453 , vital:37973 , ISBN 9783642179822 , DOI: 10.1007/978-3-642-17983-9_5
- Description: There is an increasing awareness that monetary value does not fully represent the complete value and significance of NTFPs. Consequently, there is growing interest in the cultural dimensions of biodiversity and the role that it plays in human well-being. This chapter presents two case studies, one on traditional brooms in South Africa, and the other on amate paper in Mexico, to demonstrate the importance of cultural values on driving demand for NTFPs. Because cultural values are so deeply embedded, the demand for culturally valued NTFPs continue across the rural-urban divide, and are maintained even by modernising urban communities. This poses particular challenges, not only for conservation of the NTFPs, but also to sustain cultural diversity in a rapidly changing world.
- Full Text:
- Date Issued: 2011
Developing visual images for communicating information aboutantiretroviral side effects to a low-literate population:
- Dowse, Roslind, Ramela, Thato, Barford, Kirsty-Lee, Browne, Sara H
- Authors: Dowse, Roslind , Ramela, Thato , Barford, Kirsty-Lee , Browne, Sara H
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156769 , vital:40048 , https://doi.org/10.2989/16085906.2010.530172
- Description: The side effects of antiretroviral (ARV) therapy are linked to altered quality of life and adherence. Poor adherence has also been associated with low health-literacy skills, with an uninformed patient more likely to make ARV-related decisions that compromise the efficacy of the treatment. Low literacy skills disempower patients in interactions with healthcare providers and preclude the use of existing written patient information materials, which are generally written at a high reading level. Visual images or pictograms used as a counselling tool or included in patient information leaflets have been shown to improve patients’ knowledge, particularly in low-literate groups. The objective of this study was to design visuals or pictograms illustrating various ARV side effects and to evaluate them in a low-literate South African Xhosa population. Core images were generated either from a design workshop or from posed photos or images from textbooks. The research team worked closely with a graphic artist. Initial versions of the images were discussed and assessed in group discussions, and then modified and eventually evaluated quantitatively in individual interviews with 40 participants who each had a maximum of 10 years of schooling.
- Full Text:
- Date Issued: 2011
- Authors: Dowse, Roslind , Ramela, Thato , Barford, Kirsty-Lee , Browne, Sara H
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/156769 , vital:40048 , https://doi.org/10.2989/16085906.2010.530172
- Description: The side effects of antiretroviral (ARV) therapy are linked to altered quality of life and adherence. Poor adherence has also been associated with low health-literacy skills, with an uninformed patient more likely to make ARV-related decisions that compromise the efficacy of the treatment. Low literacy skills disempower patients in interactions with healthcare providers and preclude the use of existing written patient information materials, which are generally written at a high reading level. Visual images or pictograms used as a counselling tool or included in patient information leaflets have been shown to improve patients’ knowledge, particularly in low-literate groups. The objective of this study was to design visuals or pictograms illustrating various ARV side effects and to evaluate them in a low-literate South African Xhosa population. Core images were generated either from a design workshop or from posed photos or images from textbooks. The research team worked closely with a graphic artist. Initial versions of the images were discussed and assessed in group discussions, and then modified and eventually evaluated quantitatively in individual interviews with 40 participants who each had a maximum of 10 years of schooling.
- Full Text:
- Date Issued: 2011
In service to the law: Alastair James Kerr SC
- Authors: Glover, Graham B
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70658 , vital:29686 , https://hdl.handle.net/10520/EJC53959
- Description: Professor Alastair James Kerr SC passed away at Settlers Hospital in Grahamstown on the 29th of September 2010. He was eighty-eight years of age. Ironically, his death occurred at the time that the third part of the 2010 SALJ appeared in print, containing a tribute to one of the other great writers on South African contract law, Professor Richard (Dick) Christie, who had passed away earlier in the year (see A J G Lang 'Professor Richard Hunter Christie: A memorial tribute' (2010) 127 SALJ 414). 2010 may have been a momentous year in South Africa for many reasons, but the deaths of these two men in the same year has left the landscape of our contract law irrevocably changed, even though their ideas will live on through their published works.
- Full Text: false
- Date Issued: 2011
- Authors: Glover, Graham B
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/70658 , vital:29686 , https://hdl.handle.net/10520/EJC53959
- Description: Professor Alastair James Kerr SC passed away at Settlers Hospital in Grahamstown on the 29th of September 2010. He was eighty-eight years of age. Ironically, his death occurred at the time that the third part of the 2010 SALJ appeared in print, containing a tribute to one of the other great writers on South African contract law, Professor Richard (Dick) Christie, who had passed away earlier in the year (see A J G Lang 'Professor Richard Hunter Christie: A memorial tribute' (2010) 127 SALJ 414). 2010 may have been a momentous year in South Africa for many reasons, but the deaths of these two men in the same year has left the landscape of our contract law irrevocably changed, even though their ideas will live on through their published works.
- Full Text: false
- Date Issued: 2011
Report on the Mesozoic volcanic and intrusive rocks on the Namibe Basin, Southwest Angola:
- Authors: Marsh, Julian S
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144846 , vital:38384
- Description: The Bero Volcanic Complex comprises a diverse group of quartz latite and tholeiitic basalt lavas, pyroclastic and volcaniclastic deposits, aeolian sandstones as well as intrusive tholeiitic mafic dykes and gabbros. Only the silicic members of this suite have received prior attention being referred to as “granitic porphyries” by Carvalho (1961) who regarded them as being Precambrian in age. Alberti et al.(1992) informally referred to these silicic rocks as the ‘Giraul Volcanics’ and correlated them with the early Cretaceous Paraná-Etendeka Igneous Province of Brazil and Namibia.
- Full Text:
- Date Issued: 2011
- Authors: Marsh, Julian S
- Date: 2011
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/144846 , vital:38384
- Description: The Bero Volcanic Complex comprises a diverse group of quartz latite and tholeiitic basalt lavas, pyroclastic and volcaniclastic deposits, aeolian sandstones as well as intrusive tholeiitic mafic dykes and gabbros. Only the silicic members of this suite have received prior attention being referred to as “granitic porphyries” by Carvalho (1961) who regarded them as being Precambrian in age. Alberti et al.(1992) informally referred to these silicic rocks as the ‘Giraul Volcanics’ and correlated them with the early Cretaceous Paraná-Etendeka Igneous Province of Brazil and Namibia.
- Full Text:
- Date Issued: 2011
Introduction to Psychology in Industry: IPS 121F
- Murugan, C, Nel, A
- Authors: Murugan, C , Nel, A
- Date: 2011-01
- Subjects: Psychology, Industrial
- Language: English
- Type: Examination paper
- Identifier: vital:17491 , http://hdl.handle.net/10353/d1010466
- Description: Introduction to Psychology in Industry: IP S121F, Foundation programme examination paper January 2011.
- Full Text: false
- Date Issued: 2011-01
- Authors: Murugan, C , Nel, A
- Date: 2011-01
- Subjects: Psychology, Industrial
- Language: English
- Type: Examination paper
- Identifier: vital:17491 , http://hdl.handle.net/10353/d1010466
- Description: Introduction to Psychology in Industry: IP S121F, Foundation programme examination paper January 2011.
- Full Text: false
- Date Issued: 2011-01
General Management: BEC 322 & 322E
- Puchert, Juliet, Rowles, M, Fatoki, O O, Tait, M
- Authors: Puchert, Juliet , Rowles, M , Fatoki, O O , Tait, M
- Date: 2010-11
- Subjects: Management -- Examinations, questions, etc.
- Language: English
- Type: Examination paper
- Identifier: vital:17456 , http://hdl.handle.net/10353/d1010270
- Description: General Management: BEC 322 & 322E, examination November 2010.
- Full Text: false
- Date Issued: 2010-11
- Authors: Puchert, Juliet , Rowles, M , Fatoki, O O , Tait, M
- Date: 2010-11
- Subjects: Management -- Examinations, questions, etc.
- Language: English
- Type: Examination paper
- Identifier: vital:17456 , http://hdl.handle.net/10353/d1010270
- Description: General Management: BEC 322 & 322E, examination November 2010.
- Full Text: false
- Date Issued: 2010-11
Introduction to Crop Science: AGC 121 & AGC 121F
- Owusu-Aduomi O K, Mutengwa, C
- Authors: Owusu-Aduomi O K , Mutengwa, C
- Date: 2010-11
- Language: English
- Type: Examination paper
- Identifier: vital:17644 , http://hdl.handle.net/10353/d1010022
- Description: Introduction to Crop Science: AGC 121 & AGC 121F, degree examination November 2010.
- Full Text: false
- Date Issued: 2010-11
- Authors: Owusu-Aduomi O K , Mutengwa, C
- Date: 2010-11
- Language: English
- Type: Examination paper
- Identifier: vital:17644 , http://hdl.handle.net/10353/d1010022
- Description: Introduction to Crop Science: AGC 121 & AGC 121F, degree examination November 2010.
- Full Text: false
- Date Issued: 2010-11
A comparison of two sampling methods for surveying mammalian herbivore impacts on beetle communities in the canopy of Acacia drepanolobium in Kenya
- Kuria, K S, Villet, Martin H, Palmer, T, Stanton, M
- Authors: Kuria, K S , Villet, Martin H , Palmer, T , Stanton, M
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6860 , http://hdl.handle.net/10962/d1011150
- Description: Even though several methods are used to sample and monitor canopy arthropods, there are no studies to indicate which of these methods is more effective.We compared the efficacy of the beating and canopy fogging methods in collecting beetles that inhabit Acacia drepanolobium (Harms) tree canopies at Mpala Research Centre in Laikipia district, Kenya. These trees grow naturally on the black cotton soils of the Laikipia ecosystem, accounting for more than 98%of the overstorey at the study site, and are important for local cattle and wildlife production. The ultimate objective of this study was to determine the effect of differential grazing and browsing pressure from large mammalian herbivores on the beetle communities of A. drepanolobium. Seven hundred and twenty trees 1.0–2.5 m tall were sampled using each method, making a total of 1440 trees. Sampling using the two methods was done concurrently and repeated quarterly over a period of 14 months. In total, 4320 individuals were collected, 1456 by beating and 2864 by fogging. The methods jointly yielded beetle specimens from 13 families and 55 morphospecies. Fogging collected significantly more beetle morphospecies than beating, and there was a significant interaction effect between method and sampling date. We found that numerically Anthicidae and Curculionidae responded positively to the presence of cattle.We also found that Anthicidae sp. A and Myllocerus sp. A numbers significantly increased in plots where livestock were grazed.
- Full Text:
- Date Issued: 2010
- Authors: Kuria, K S , Villet, Martin H , Palmer, T , Stanton, M
- Date: 2010
- Language: English
- Type: Article
- Identifier: vital:6860 , http://hdl.handle.net/10962/d1011150
- Description: Even though several methods are used to sample and monitor canopy arthropods, there are no studies to indicate which of these methods is more effective.We compared the efficacy of the beating and canopy fogging methods in collecting beetles that inhabit Acacia drepanolobium (Harms) tree canopies at Mpala Research Centre in Laikipia district, Kenya. These trees grow naturally on the black cotton soils of the Laikipia ecosystem, accounting for more than 98%of the overstorey at the study site, and are important for local cattle and wildlife production. The ultimate objective of this study was to determine the effect of differential grazing and browsing pressure from large mammalian herbivores on the beetle communities of A. drepanolobium. Seven hundred and twenty trees 1.0–2.5 m tall were sampled using each method, making a total of 1440 trees. Sampling using the two methods was done concurrently and repeated quarterly over a period of 14 months. In total, 4320 individuals were collected, 1456 by beating and 2864 by fogging. The methods jointly yielded beetle specimens from 13 families and 55 morphospecies. Fogging collected significantly more beetle morphospecies than beating, and there was a significant interaction effect between method and sampling date. We found that numerically Anthicidae and Curculionidae responded positively to the presence of cattle.We also found that Anthicidae sp. A and Myllocerus sp. A numbers significantly increased in plots where livestock were grazed.
- Full Text:
- Date Issued: 2010
An assessment of a light-attraction fishery in southern Lake Malawi
- Weyl, Olaf L F, Kazembe, Jacqueline, Booth, Anthony J, Mandere, D S
- Authors: Weyl, Olaf L F , Kazembe, Jacqueline , Booth, Anthony J , Mandere, D S
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123683 , vital:35472 , https://doi.org/10.2989/16085910409503787
- Description: This study provides the first quantitative assessment of the light-attraction component of a small-scale purse seine, locally known as a chilimira net, fishery in two areas of southern Lake Malawi. For monitoring purposes the shoreline of Lake Malawi is divided into a number of statistical strata. Two strata (‘2.1’ in the southeast arm and ‘3.1’ in the southwest arm of the lake) were selected for this study. Catch per unit effort in stratum 2.1 was generally lower than that recorded in stratum 3.1 but nets in stratum 2.1 fished more frequently, leading to similar annual catches in the two strata. Annual catch was estimated as 19.4 (CI = 15.9–23.5) tons net–1 year–1 in stratum 2.1 and 23.5 (CI = 19.5–28.1) tons net–1 year–1 in stratum 3.1 respectively. A total of 62 species from 28 cichlid genera, and 13 species from nine non-cichlid genera, were identified from the samples. Of the 37 genera identified, only five; Copadichromis, Dimidiochromis, Engraulicypris, Oreochromis and Rhamphochromis, contributed more than 5% to the total annual catch in either stratum. Their combined contribution to the annual catch was in excess of 85% in both strata. Comparisons showed that catch-composition was dependent on area. Length-frequency distributions of major target species in the catch showed that the fishery targeted juveniles in stratum 2.1, while in stratum 3.1 most individuals were harvested after reaching their lengthat-maturity. The dependence of catch-composition and size-selection on area indicates that management interventions for this fishery need to be area-specific. Since the fishery targets a diverse species assemblage, effort limitation or area closure may be the only viable management options, until such time as additional biological and fisheries data are available for the application of stock assessment models.
- Full Text:
- Date Issued: 2010
- Authors: Weyl, Olaf L F , Kazembe, Jacqueline , Booth, Anthony J , Mandere, D S
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/123683 , vital:35472 , https://doi.org/10.2989/16085910409503787
- Description: This study provides the first quantitative assessment of the light-attraction component of a small-scale purse seine, locally known as a chilimira net, fishery in two areas of southern Lake Malawi. For monitoring purposes the shoreline of Lake Malawi is divided into a number of statistical strata. Two strata (‘2.1’ in the southeast arm and ‘3.1’ in the southwest arm of the lake) were selected for this study. Catch per unit effort in stratum 2.1 was generally lower than that recorded in stratum 3.1 but nets in stratum 2.1 fished more frequently, leading to similar annual catches in the two strata. Annual catch was estimated as 19.4 (CI = 15.9–23.5) tons net–1 year–1 in stratum 2.1 and 23.5 (CI = 19.5–28.1) tons net–1 year–1 in stratum 3.1 respectively. A total of 62 species from 28 cichlid genera, and 13 species from nine non-cichlid genera, were identified from the samples. Of the 37 genera identified, only five; Copadichromis, Dimidiochromis, Engraulicypris, Oreochromis and Rhamphochromis, contributed more than 5% to the total annual catch in either stratum. Their combined contribution to the annual catch was in excess of 85% in both strata. Comparisons showed that catch-composition was dependent on area. Length-frequency distributions of major target species in the catch showed that the fishery targeted juveniles in stratum 2.1, while in stratum 3.1 most individuals were harvested after reaching their lengthat-maturity. The dependence of catch-composition and size-selection on area indicates that management interventions for this fishery need to be area-specific. Since the fishery targets a diverse species assemblage, effort limitation or area closure may be the only viable management options, until such time as additional biological and fisheries data are available for the application of stock assessment models.
- Full Text:
- Date Issued: 2010
Beyond teaching language: towards terminological primacy in learners' geometric conceptualisation
- Atebe, Humphrey U, Schäfer, Marc
- Authors: Atebe, Humphrey U , Schäfer, Marc
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140960 , vital:37932 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC20922
- Description: This paper reports on a specific aspect of a broader geometry conceptualisation study that sought to explore and explicate learners' knowledge of basic geometric terminology in selected Nigerian and South African high schools. It is framed by the notion that students' acquisition of the correct terminology in school geometry is important for their success in the subject. The original study further aimed to determine the relationship that might exist between a learner's ability in verbal geometry terminology tasks and his/her ability in visual geometry terminology tasks. A total of 144 learners (72 each from South Africa and Nigeria) were selected for the study, using both the stratified and the fish-bowl sampling techniques. A questionnaire consisting of a sixty-item multiple-choice objective test provided the data for the study. An overall percentage mean score of 44,17% obtained in the test indicated that learners in this study had only a limited knowledge of basic geometric terminology. The Nigerian subsample in the study had a weaker understanding of basic geometric terminology than their South African counterparts. Importantly, there were high positive correlations between participants' ability in verbal geometry terminology tasks and their ability in visual geometry terminology tasks. These results are consistent with those of several earlier studies, and provide a reasonably firm basis for certain recommendations to be made.
- Full Text:
- Date Issued: 2010
- Authors: Atebe, Humphrey U , Schäfer, Marc
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/140960 , vital:37932 , https://0-hdl.handle.net.wam.seals.ac.za/10520/EJC20922
- Description: This paper reports on a specific aspect of a broader geometry conceptualisation study that sought to explore and explicate learners' knowledge of basic geometric terminology in selected Nigerian and South African high schools. It is framed by the notion that students' acquisition of the correct terminology in school geometry is important for their success in the subject. The original study further aimed to determine the relationship that might exist between a learner's ability in verbal geometry terminology tasks and his/her ability in visual geometry terminology tasks. A total of 144 learners (72 each from South Africa and Nigeria) were selected for the study, using both the stratified and the fish-bowl sampling techniques. A questionnaire consisting of a sixty-item multiple-choice objective test provided the data for the study. An overall percentage mean score of 44,17% obtained in the test indicated that learners in this study had only a limited knowledge of basic geometric terminology. The Nigerian subsample in the study had a weaker understanding of basic geometric terminology than their South African counterparts. Importantly, there were high positive correlations between participants' ability in verbal geometry terminology tasks and their ability in visual geometry terminology tasks. These results are consistent with those of several earlier studies, and provide a reasonably firm basis for certain recommendations to be made.
- Full Text:
- Date Issued: 2010
Framework for local government to implement integrated water resource management linked to water service delivery
- Haigh, Eliria H, Fox, Helen E, Davies-Coleman, H D
- Authors: Haigh, Eliria H , Fox, Helen E , Davies-Coleman, H D
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:7097 , http://hdl.handle.net/10962/d1012440
- Description: The Water Services Act (No. 8 of 1997) of South Africa states that water service delivery is the responsibility of local government as Water Services Authorities. The principal legal responsibility is to complete a Water Services Development Plan (WSDP) every 5 years with annual review. The WSDP encapsulates all the responsibilities and tasks required in water service delivery. However, it does not spell out local government’s role in water resource protection or its responsibilities as far as integrated water resource management is concerned. It is well known in South Africa that there is a challenging level of inadequate capacity in technical and administrative skills in local government to adequately fulfil water service delivery. This paper highlights the consequences of this incapacity for municipalities and their difficulties in fulfilling their responsibilities as service providers. A framework is provided within which improvements can be brought about, with guidance on how to engage in the practice of integrated water resource management (IWRM) in the context of the legal framework for water services. The additional tasks and changes required to practise IWRM are set in the context of the WSDP. The framework provides a guide for a municipality to first accomplish an adequate WSDP, and then to gradually implement IWRM. A discussion on the skills needed to accomplish, firstly, a comprehensive WSDP, and secondly, IWRM, is included.
- Full Text:
- Date Issued: 2010
- Authors: Haigh, Eliria H , Fox, Helen E , Davies-Coleman, H D
- Date: 2010
- Language: English
- Type: text , Article
- Identifier: vital:7097 , http://hdl.handle.net/10962/d1012440
- Description: The Water Services Act (No. 8 of 1997) of South Africa states that water service delivery is the responsibility of local government as Water Services Authorities. The principal legal responsibility is to complete a Water Services Development Plan (WSDP) every 5 years with annual review. The WSDP encapsulates all the responsibilities and tasks required in water service delivery. However, it does not spell out local government’s role in water resource protection or its responsibilities as far as integrated water resource management is concerned. It is well known in South Africa that there is a challenging level of inadequate capacity in technical and administrative skills in local government to adequately fulfil water service delivery. This paper highlights the consequences of this incapacity for municipalities and their difficulties in fulfilling their responsibilities as service providers. A framework is provided within which improvements can be brought about, with guidance on how to engage in the practice of integrated water resource management (IWRM) in the context of the legal framework for water services. The additional tasks and changes required to practise IWRM are set in the context of the WSDP. The framework provides a guide for a municipality to first accomplish an adequate WSDP, and then to gradually implement IWRM. A discussion on the skills needed to accomplish, firstly, a comprehensive WSDP, and secondly, IWRM, is included.
- Full Text:
- Date Issued: 2010
Growth and longevity of Exosphaeroma hylocoetes (Isopoda) under varying conditions of salinity and temperature
- Henninger, Tony O, Froneman, P William, Booth, Anthony J, Hodgson, Alan N
- Authors: Henninger, Tony O , Froneman, P William , Booth, Anthony J , Hodgson, Alan N
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124571 , vital:35630 , https://doi.org/10.3377/004.045.0118
- Description: Numerous studies have documented the importance of both temperature and salinity in influencing aquatic crustacean metabolic processes such as respiration and growth. For example, increased water temperatures have been shown to increase respiration rates in various species of shrimp (Chen & Nan 1993; Spanonopoulos-Hernándeza et al. 2005; Allan et al. 2006), and copepods (Isla & Perissinotto 2004). The response of invertebrates to changes in salinity is more complex, largely reflecting their evolutionary origins (Kinne 1966). For example, juvenile blue swimming crabs, Portunus pelagicus, displayed significantly faster growth and higher survival in response to increasingsalinity (Romano & Zeng 2006). Additional factors that may influence the growth rates of crustaceans include photoperiod (Gambardella et al. 1997), food availability (Shuster & Guthrie 1999) and sex (Newman et al. 2007).
- Full Text:
- Date Issued: 2010
- Authors: Henninger, Tony O , Froneman, P William , Booth, Anthony J , Hodgson, Alan N
- Date: 2010
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/124571 , vital:35630 , https://doi.org/10.3377/004.045.0118
- Description: Numerous studies have documented the importance of both temperature and salinity in influencing aquatic crustacean metabolic processes such as respiration and growth. For example, increased water temperatures have been shown to increase respiration rates in various species of shrimp (Chen & Nan 1993; Spanonopoulos-Hernándeza et al. 2005; Allan et al. 2006), and copepods (Isla & Perissinotto 2004). The response of invertebrates to changes in salinity is more complex, largely reflecting their evolutionary origins (Kinne 1966). For example, juvenile blue swimming crabs, Portunus pelagicus, displayed significantly faster growth and higher survival in response to increasingsalinity (Romano & Zeng 2006). Additional factors that may influence the growth rates of crustaceans include photoperiod (Gambardella et al. 1997), food availability (Shuster & Guthrie 1999) and sex (Newman et al. 2007).
- Full Text:
- Date Issued: 2010