South African anthropometric dimensions for the design of an ergonomic office chair
- Authors: Korte, Janice
- Date: 2013 , 2013-09-05
- Subjects: Design -- Human factors , Office chairs , Chair design , Human engineering , Sitting position
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5137 , http://hdl.handle.net/10962/d1006046 , Design -- Human factors , Office chairs , Chair design , Human engineering , Sitting position
- Description: Office chairs are becoming a modern status symbol in the workplace. Many individuals are seated on office chairs for most of the working day. As a result of using poorly designed chairs injury and discomfort are frequently experienced, most particularly lower back pain. Correct design of chairs is imperative, and must be user-centered. The aim of this investigation has been to gather anthropometric dimensions characteristic of the South African population, as this information has not been widely assimilated to date. Once collated, this information could be used in the design of an ergonomically correct office chair, suitable for the unique characteristics of the South African working population. Anthropometric dimensions were collected from 683 South Africans (comprising 448 South African females and 235 South African males) from pre-selected companies in major centres in South Africa (Johannesburg, Pietermaritzburg, Durban, East London, Grahamstown, Port Elizabeth and Cape Town). Measurements included participants’ personal information (age, sex, home language and ethnic group), basic anthropometric measures (stature, shoulder height, mass, and waist and hip circumference) as well as specific measures of fit of the individual to the specially designed, adjustable chair. Of the 448 females, 317 were Black females, 77 were White females, 35 were Coloured females and 19 were Indian/Asian females. Of the 235 males, 112 were Black males, 79 were White males, 26 were Coloured males and 18 were Indian/Asian males. Office chair dimensions for each ethnic group were represented and differences were noted. A comparison between a current office chair’s dimensions and the South African sample office chair’s dimensions indicated modifications that would need to be constructed to suit the South African sample. The conventional office chair is still the most widely accepted office chair due to its stability and support structures that maintain the correct sitting posture of the user. An ergonomic office chair needs to incorporate anthropometric dimensions worldwide.
- Full Text:
- Date Issued: 2013
- Authors: Korte, Janice
- Date: 2013 , 2013-09-05
- Subjects: Design -- Human factors , Office chairs , Chair design , Human engineering , Sitting position
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5137 , http://hdl.handle.net/10962/d1006046 , Design -- Human factors , Office chairs , Chair design , Human engineering , Sitting position
- Description: Office chairs are becoming a modern status symbol in the workplace. Many individuals are seated on office chairs for most of the working day. As a result of using poorly designed chairs injury and discomfort are frequently experienced, most particularly lower back pain. Correct design of chairs is imperative, and must be user-centered. The aim of this investigation has been to gather anthropometric dimensions characteristic of the South African population, as this information has not been widely assimilated to date. Once collated, this information could be used in the design of an ergonomically correct office chair, suitable for the unique characteristics of the South African working population. Anthropometric dimensions were collected from 683 South Africans (comprising 448 South African females and 235 South African males) from pre-selected companies in major centres in South Africa (Johannesburg, Pietermaritzburg, Durban, East London, Grahamstown, Port Elizabeth and Cape Town). Measurements included participants’ personal information (age, sex, home language and ethnic group), basic anthropometric measures (stature, shoulder height, mass, and waist and hip circumference) as well as specific measures of fit of the individual to the specially designed, adjustable chair. Of the 448 females, 317 were Black females, 77 were White females, 35 were Coloured females and 19 were Indian/Asian females. Of the 235 males, 112 were Black males, 79 were White males, 26 were Coloured males and 18 were Indian/Asian males. Office chair dimensions for each ethnic group were represented and differences were noted. A comparison between a current office chair’s dimensions and the South African sample office chair’s dimensions indicated modifications that would need to be constructed to suit the South African sample. The conventional office chair is still the most widely accepted office chair due to its stability and support structures that maintain the correct sitting posture of the user. An ergonomic office chair needs to incorporate anthropometric dimensions worldwide.
- Full Text:
- Date Issued: 2013
Dasein online! a study of the experience of flow in the virtual playground
- Authors: Godley, Donnae-Maree
- Date: 2012
- Subjects: Internet games -- Social aspects -- Research , Virtual reality -- Social aspects -- Research , Fantasy games -- Social aspects -- Research , Human-computer interaction -- Research , Online identities
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2983 , http://hdl.handle.net/10962/d1002492 , Internet games -- Social aspects -- Research , Virtual reality -- Social aspects -- Research , Fantasy games -- Social aspects -- Research , Human-computer interaction -- Research , Online identities
- Description: The purpose of this study was twofold. First, it aimed to present and understand the experiences of online gamers from the paradigm of positive psychology. To achieve this, the phenomenon of flow was investigated to see whether or not, it is experienced whilst gaming online and if present, how it is revealed in this context. The second purpose was to contribute to theory building and to respond to extant research recommendations. Aligned with a qualitative orientation, the method selected to achieve the objectives of the study was interpretative phenomenological analysis. A sample of four participants who met the criteria for inclusion in the research were selected and interviewed using semi-structured interviews. Data was analysed and interpreted inductively and categorised into superordinate themes. These were presented as two sections: Section A explored the experience and meaning of online gaming through the following three superordinate themes; intention, pre-gaming rituals and gaming process. Section B discussed the social experience and meaning of gaming online through the superordinate theme, a gamers way. This study both challenged and supported theory and research in the field and introduced novel areas, such as pregaming rituals and the subthemes; marijuana and gaming space. This is a notable and promising "side effect" of a research design that is exploratory. Findings called for future multi-disciplinary research into flow, gaming and online relationships considering Csikszentimaihalyi‟s concept of autotelic relationships and Heideggers‟ philosophical framework.
- Full Text:
- Date Issued: 2012
- Authors: Godley, Donnae-Maree
- Date: 2012
- Subjects: Internet games -- Social aspects -- Research , Virtual reality -- Social aspects -- Research , Fantasy games -- Social aspects -- Research , Human-computer interaction -- Research , Online identities
- Language: English
- Type: Thesis , Masters , MSocSc
- Identifier: vital:2983 , http://hdl.handle.net/10962/d1002492 , Internet games -- Social aspects -- Research , Virtual reality -- Social aspects -- Research , Fantasy games -- Social aspects -- Research , Human-computer interaction -- Research , Online identities
- Description: The purpose of this study was twofold. First, it aimed to present and understand the experiences of online gamers from the paradigm of positive psychology. To achieve this, the phenomenon of flow was investigated to see whether or not, it is experienced whilst gaming online and if present, how it is revealed in this context. The second purpose was to contribute to theory building and to respond to extant research recommendations. Aligned with a qualitative orientation, the method selected to achieve the objectives of the study was interpretative phenomenological analysis. A sample of four participants who met the criteria for inclusion in the research were selected and interviewed using semi-structured interviews. Data was analysed and interpreted inductively and categorised into superordinate themes. These were presented as two sections: Section A explored the experience and meaning of online gaming through the following three superordinate themes; intention, pre-gaming rituals and gaming process. Section B discussed the social experience and meaning of gaming online through the superordinate theme, a gamers way. This study both challenged and supported theory and research in the field and introduced novel areas, such as pregaming rituals and the subthemes; marijuana and gaming space. This is a notable and promising "side effect" of a research design that is exploratory. Findings called for future multi-disciplinary research into flow, gaming and online relationships considering Csikszentimaihalyi‟s concept of autotelic relationships and Heideggers‟ philosophical framework.
- Full Text:
- Date Issued: 2012
Trophic ecology of breeding northern rockhopper penguins, Eudyptes Moseleyi, at Tristan da Cunha, South Atlantic Ocean
- Authors: Booth, Jenny Marie
- Date: 2012
- Subjects: Penguins -- Breeding -- Tristan da Cunha , Penguins -- Ecology -- Tristan da Cunha , Penguins -- Food
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5788 , http://hdl.handle.net/10962/d1005476 , Penguins -- Breeding -- Tristan da Cunha , Penguins -- Ecology -- Tristan da Cunha , Penguins -- Food
- Description: Northern Rockhopper penguin populations, Eudyptes moseleyi, are declining globally, and at Tristan da Cunha have undergone severe declines (> 90% in the last 130 years), the cause(s)of which are unknown. There is a paucity of data on this species in the South Atlantic Ocean, therefore their trophic ecology at Tristan da Cunha was studied, specifically focusing on diet, using stomach content analysis and stable isotope analysis (SIA), in conjunction with an analysis of diving behaviour, assessed using temperature-depth recorders. In order to evaluate the influence of gender on foraging, a morphometric investigation of sexual dimorphism was confirmed using molecular analysis. Additionally, plasma corticosterone levels were measured to examine breeding stage and presence of blood parasites as potential sources of stress during the breeding season. Northern Rockhopper penguins at Tristan da Cunha displayed a high degree of foraging plasticity, and fed opportunistically on a wide variety of prey, probably reflecting local small-scale changes in prey distribution. Zooplankton dominated (by mass) the diet of guard stage females, whereas small meso-pelagic fish (predominantly Photichthyidae)dominated diet of adults of both sexes in the crèche stage, with cephalopods contributing equally in both stages. Adults consistently fed chicks on lower-trophic level prey (assessed using SIA), probably zooplankton, than they consumed themselves indicating that the increasing demands of growing chicks were not met by adults through provisioning of higher- quality prey. SIA also indicated that adults foraged in different oceanic water masses when feeding for self-maintenance and for chick provisioning, thus temporally segregating the prey consumed for different purposes. It is possible that adults ‘selected’ these higher quality prey for themselves, or this may be a reflection of opportunistic behaviour. At Tristan da Cunha sexual dimorphism was observed in culmen dimensions (length, depth, width), with males having larger beaks and feeding on larger individuals of squid and fish than females. No sexual segregation in terms of foraging habitat (i.e. different water masses, based on ð¹³N or trophic level ð¹⁵N) during the breeding season or pre-moult period was revealed through SIA, and stomach content analysis revealed no sexual differences in prey species targeted. The results of SIA of feathers indicate that during the pre-moult period birds foraged in different water masses than during the breeding period. The fact that throughout the breeding season birds foraged in similar habitats suggests no intra-specific competition, despite both sexes feeding on the same prey.Birds were generally diurnal, daily foragers (12 – 16 hr trips), with extended trips (maximum duration 35.5 hours) and nocturnal diving recorded in a few individuals. Birds dived well within their physiological limits, predominantly utilising the upper 20m of the water column, employing two different strategies to target different prey items. Long, deep (30 – 40 m), energetically costly dives were performed when targeting energy-rich prey (fish), and a greater number of shorter, shallower (5 – 20 m), energy-efficient dives were performed when targeting prey with a lower energy content (zooplankton). More than half of the sampled study population were infected with the intra-cellular blood parasite Babesia, but infection showed no relationship to body mass, corticosterone levels or breeding success. Fasting birds showed no signs of elevated corticosterone levels, suggesting they had acquired sufficient fat reserves prior to breeding. Failed breeders did not exhibit elevated corticosterone levels. Tristan skuas, Catharacta antarctica hamiltoni, were observed to be a significant cause of egg and chick mortality. The absence of sex-based differences in foraging, and the absence of any signs of stress in relation to body mass, presence of Babesia or breeding stage, suggest that there are no obvious signs of high levels of stress or food limitations during breeding at Tristan da Cunha.
- Full Text:
- Date Issued: 2012
- Authors: Booth, Jenny Marie
- Date: 2012
- Subjects: Penguins -- Breeding -- Tristan da Cunha , Penguins -- Ecology -- Tristan da Cunha , Penguins -- Food
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5788 , http://hdl.handle.net/10962/d1005476 , Penguins -- Breeding -- Tristan da Cunha , Penguins -- Ecology -- Tristan da Cunha , Penguins -- Food
- Description: Northern Rockhopper penguin populations, Eudyptes moseleyi, are declining globally, and at Tristan da Cunha have undergone severe declines (> 90% in the last 130 years), the cause(s)of which are unknown. There is a paucity of data on this species in the South Atlantic Ocean, therefore their trophic ecology at Tristan da Cunha was studied, specifically focusing on diet, using stomach content analysis and stable isotope analysis (SIA), in conjunction with an analysis of diving behaviour, assessed using temperature-depth recorders. In order to evaluate the influence of gender on foraging, a morphometric investigation of sexual dimorphism was confirmed using molecular analysis. Additionally, plasma corticosterone levels were measured to examine breeding stage and presence of blood parasites as potential sources of stress during the breeding season. Northern Rockhopper penguins at Tristan da Cunha displayed a high degree of foraging plasticity, and fed opportunistically on a wide variety of prey, probably reflecting local small-scale changes in prey distribution. Zooplankton dominated (by mass) the diet of guard stage females, whereas small meso-pelagic fish (predominantly Photichthyidae)dominated diet of adults of both sexes in the crèche stage, with cephalopods contributing equally in both stages. Adults consistently fed chicks on lower-trophic level prey (assessed using SIA), probably zooplankton, than they consumed themselves indicating that the increasing demands of growing chicks were not met by adults through provisioning of higher- quality prey. SIA also indicated that adults foraged in different oceanic water masses when feeding for self-maintenance and for chick provisioning, thus temporally segregating the prey consumed for different purposes. It is possible that adults ‘selected’ these higher quality prey for themselves, or this may be a reflection of opportunistic behaviour. At Tristan da Cunha sexual dimorphism was observed in culmen dimensions (length, depth, width), with males having larger beaks and feeding on larger individuals of squid and fish than females. No sexual segregation in terms of foraging habitat (i.e. different water masses, based on ð¹³N or trophic level ð¹⁵N) during the breeding season or pre-moult period was revealed through SIA, and stomach content analysis revealed no sexual differences in prey species targeted. The results of SIA of feathers indicate that during the pre-moult period birds foraged in different water masses than during the breeding period. The fact that throughout the breeding season birds foraged in similar habitats suggests no intra-specific competition, despite both sexes feeding on the same prey.Birds were generally diurnal, daily foragers (12 – 16 hr trips), with extended trips (maximum duration 35.5 hours) and nocturnal diving recorded in a few individuals. Birds dived well within their physiological limits, predominantly utilising the upper 20m of the water column, employing two different strategies to target different prey items. Long, deep (30 – 40 m), energetically costly dives were performed when targeting energy-rich prey (fish), and a greater number of shorter, shallower (5 – 20 m), energy-efficient dives were performed when targeting prey with a lower energy content (zooplankton). More than half of the sampled study population were infected with the intra-cellular blood parasite Babesia, but infection showed no relationship to body mass, corticosterone levels or breeding success. Fasting birds showed no signs of elevated corticosterone levels, suggesting they had acquired sufficient fat reserves prior to breeding. Failed breeders did not exhibit elevated corticosterone levels. Tristan skuas, Catharacta antarctica hamiltoni, were observed to be a significant cause of egg and chick mortality. The absence of sex-based differences in foraging, and the absence of any signs of stress in relation to body mass, presence of Babesia or breeding stage, suggest that there are no obvious signs of high levels of stress or food limitations during breeding at Tristan da Cunha.
- Full Text:
- Date Issued: 2012
The design, implementation and evaluation of an English language development component within a Grahamstown community project
- Authors: Jefferay, Charlotte Ruth
- Date: 1994
- Subjects: Grahamstown Tertiary Education Bridging Project , English language -- Study and teaching -- South Africa -- Foreign speakers , English language -- Writing -- Study and teaching -- South Africa -- Foreign speakers
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2351 , http://hdl.handle.net/10962/d1002633 , Grahamstown Tertiary Education Bridging Project , English language -- Study and teaching -- South Africa -- Foreign speakers , English language -- Writing -- Study and teaching -- South Africa -- Foreign speakers
- Description: The Grahamstown Tertiary Education Bridging Project (GRATEP) was formed in 1991 by a group of post-matriculants from Grahamstown who had not been accepted into any tertiary institution for 1991. The overall aim of GRATEP was to prepare these students for tertiary education. The Academic Skills Programme at Rhodes University offered a programme in English Language Development. The present study aimed to research the design, implementation and evaluation of the GRATEP English Language Development programme which was implemented from May through to October 1991. A multimethod approach has been used to assess the progress made by the students in terms of developing communicative competence in English and to evaluate the course itself. The data included writing samples, questionnaires, exercises in hierarchical organization, a clozetest, comments made by the students and the participant observers. The programme appeared to have been most effective in terms of building confidence, developing academic skills and encouraging the students to take greater responsibility for their own learning. Statistical comparisons of the first and final writing samples revealed no overall significant improvement in communicative competence in English. However, comparisons of the scores in the categories and sub-categories of communicative competence revealed that students had improved in their ability to structure and organize their writing. The research raised questions about the design, implementation and assessment of non-formal language courses of this kind and made suggestions for improvement and further research.
- Full Text:
- Date Issued: 1994
- Authors: Jefferay, Charlotte Ruth
- Date: 1994
- Subjects: Grahamstown Tertiary Education Bridging Project , English language -- Study and teaching -- South Africa -- Foreign speakers , English language -- Writing -- Study and teaching -- South Africa -- Foreign speakers
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2351 , http://hdl.handle.net/10962/d1002633 , Grahamstown Tertiary Education Bridging Project , English language -- Study and teaching -- South Africa -- Foreign speakers , English language -- Writing -- Study and teaching -- South Africa -- Foreign speakers
- Description: The Grahamstown Tertiary Education Bridging Project (GRATEP) was formed in 1991 by a group of post-matriculants from Grahamstown who had not been accepted into any tertiary institution for 1991. The overall aim of GRATEP was to prepare these students for tertiary education. The Academic Skills Programme at Rhodes University offered a programme in English Language Development. The present study aimed to research the design, implementation and evaluation of the GRATEP English Language Development programme which was implemented from May through to October 1991. A multimethod approach has been used to assess the progress made by the students in terms of developing communicative competence in English and to evaluate the course itself. The data included writing samples, questionnaires, exercises in hierarchical organization, a clozetest, comments made by the students and the participant observers. The programme appeared to have been most effective in terms of building confidence, developing academic skills and encouraging the students to take greater responsibility for their own learning. Statistical comparisons of the first and final writing samples revealed no overall significant improvement in communicative competence in English. However, comparisons of the scores in the categories and sub-categories of communicative competence revealed that students had improved in their ability to structure and organize their writing. The research raised questions about the design, implementation and assessment of non-formal language courses of this kind and made suggestions for improvement and further research.
- Full Text:
- Date Issued: 1994
A structural study of the capsular antigen of Klebsiella serotype K43
- Authors: Aereboe, Michael
- Date: 1993
- Subjects: Polysaccharides , Klebsiella , Antigens , Enterobacteriaceae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3740 , http://hdl.handle.net/10962/d1003218 , Polysaccharides , Klebsiella , Antigens , Enterobacteriaceae
- Description: This thesis presents a detailed chemical and spectroscopic determination of the capsular, polysaccharide K-antigen isolated from the Klebsiella bacterium, serotype K43 (culture #2482). The repeating unit of the capsular polysaccharide was found to be of the "3 + 2" repeating unit type. A uronic acid was found as part of a disaccharide side chain and the main chain of the polysaccharide was found to be composed of a neutral trisaccharide of mannose and galactose. The work forms part of an ongoing research interest in bacterial polysaccharides of this laboratory and now completes the structural elucidation of all the Klebsiella K-antigens, bar three antigens which were originally assigned to other laboratories. These data together with the respective serological characteristics of each serotype are available to the molecular biologist, and may result in the production of: vaccine(s) against Klebsiella infections, diagnostic products and novel carrier molecules enabling targeted drug delivery.
- Full Text:
- Date Issued: 1993
- Authors: Aereboe, Michael
- Date: 1993
- Subjects: Polysaccharides , Klebsiella , Antigens , Enterobacteriaceae
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3740 , http://hdl.handle.net/10962/d1003218 , Polysaccharides , Klebsiella , Antigens , Enterobacteriaceae
- Description: This thesis presents a detailed chemical and spectroscopic determination of the capsular, polysaccharide K-antigen isolated from the Klebsiella bacterium, serotype K43 (culture #2482). The repeating unit of the capsular polysaccharide was found to be of the "3 + 2" repeating unit type. A uronic acid was found as part of a disaccharide side chain and the main chain of the polysaccharide was found to be composed of a neutral trisaccharide of mannose and galactose. The work forms part of an ongoing research interest in bacterial polysaccharides of this laboratory and now completes the structural elucidation of all the Klebsiella K-antigens, bar three antigens which were originally assigned to other laboratories. These data together with the respective serological characteristics of each serotype are available to the molecular biologist, and may result in the production of: vaccine(s) against Klebsiella infections, diagnostic products and novel carrier molecules enabling targeted drug delivery.
- Full Text:
- Date Issued: 1993
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