Routing MIDI messages in a shared music studio environment
- Authors: Mosala, Thabo Jerry
- Date: 1995
- Subjects: MIDI (Standard) , Computer networks
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4672 , http://hdl.handle.net/10962/d1006695 , MIDI (Standard) , Computer networks
- Description: The Rhodes Computer Music Network (RHOCMN) is a network which allows main studio resources to be shared. RHOCMN is growing into a multi-workstation environment and additional devices are being incorporated into the system. A star configuration is used for transmitting MIDI from a MIDI patch bay to the workstations and MIDI devices. This imposes several disadvantages on the use of the studio, such as wiring problems. In a quest to avoid problems related to MIDI in RHOCMN, the MIDINet system was developed. The idea was to acquire a viable solution to MIDI's main problems which does not involve a redefinition of the MIDI specification.
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- Date Issued: 1995
SADTU News - A review of SADTU Congress
- Authors: SADTU
- Date: 1995
- Subjects: SADTU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/118030 , vital:34586
- Description: The Third SADTU Congress, held at the World Trade Centre in Kempton Park, was attended by over 800 delegates, representing 100 000 teachers country-wide. Delegates were elected at Branch level, ensuring grass roots participation in the highest decision making body of the Union. The Congress served to confirm SADTU’s position as the largest teacher Union in the country, and demonstrated a strongly unified focus around the theme: “Unionise and Reconstruct for Teacher Empowerment”. The success of any Congress must be measured against the aims it sets itself. Our Congress had two aims: to elect new leadership for the next two years, and to adopt resolutions which would inform the direction and programmes of the Union in this period. While we successfully completed the former task, we could only make a start on the second aspect - confirming the fact that the period we are entering is far more complex than before, and in need of extensive analysis and debate. We therefore mandated the SADTU National Council to formalise the adoption of resolutions arising from the reports. A Special National Council was convened on 25/26 August, with extended participation by regions, and the Congress report can now be finalised.
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- Date Issued: 1995
SADTU News - Model C Schools
- Authors: SADTU
- Date: 1995
- Subjects: SADTU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/161012 , vital:40580
- Description: Model C Schools have created great controversy in recent educational policy debate. SADTU has joined the fray in opposition to the retention of these schools. Model C is a particular type of state aided school which is different to state aided schools like the farm schools that came under the authority of the former black Department of Education and Training (DET). The latter schools were mostly poorly resourced and inadequately staffed. Model C schools are state aided schools that have governing bodies elected by the parents, with power over a number of key functions of the school. These include control over admissions policy, the power to charge compulsory school fees and to raise funds by other means (e.g. renting out the school's property), the power to decide how the school's money is to be spent (e.g. school maintenance, the hiring of additional teachers and other staff, the buying of books and equipment, and the power to exercise influence over the hiring and disciplining of teachers). The system is unique among state- aided schools in that Model Cs are all former state schools in the privileged white school system. Nearly all inherited a sound infrastructure provided largely by the state in the form of school buildings, grounds, libraries, laboratories etc. They also inherited a well qualified teaching staff, whose training (the best in the country) was also partly the result of public subsidies. Model C has several strengths which has led to the ongoing controversy. Parental participation in the schooling of their children has been mobilised. The governing bodies actually have power over important aspects of the school in contrast to the old comparatively toothless management councils. This, it appears, has ensured that parents, whether they approve of Model C or not, take them much more seriously since the governing bodies can take decisions which materially affect them and their children's education. In addition, this model has mobilised private resources for education and ensured that a relatively high level of provision can be maintained while state funding is decreased. Money thus saved by the state - reportedly about R1 billion - can be diverted to redressing the inadequacies of African education.
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- Date Issued: 1995
Secondary school geography teachers' perceptions of the role of environmental education in geography with particular reference to Natal Education Department teachers
- Authors: Wassermann, Johannes Michiel
- Date: 1995
- Subjects: Geography teachers -- South Africa -- KwaZulu-Natal -- Attitudes Environmental education -- South Africa -- KwaZulu-Natal
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1761 , http://hdl.handle.net/10962/d1003646
- Description: Environmental Education (EE) as a development cannot be ignored by Geography or Geographers particularly since South Africa, as the rest of the world, is confronted by a looming environmental crisis. Geography is an environmental science concerned primarily with man-environment relationships using an environmental approach to develop the skills, knowledge, values and attitudes necessary for sustainable living. Geography has a vital role to play in addressing environmental issues. In formal education Geography teachers will be responsible for the implementation of such an approach. This study therefore investigates the perceptions of Natal Senior Secondary School Geography teachers regarding the role of EE in Geography. Questionnaires and semi-structured interviews were used to determine this. The study revealed that although these teachers are well qualified and motivated they had a limited grasp of the theory underpinning current EE and Geographical thinking. Recommendations are made for the development of an environmental approach in the teaching of Geography.
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- Date Issued: 1995
Sensitive high-performance liquid chromatographic determination of cyclizine and its demethylated metabolite, norcyclizine, in biological fluids using coulometric detection
- Authors: Walker, Roderick B , Kanfer, Isadore
- Date: 1995
- Language: English
- Type: text , Article
- Identifier: vital:6452 , http://hdl.handle.net/10962/d1006640 , http://dx.doi.org/10.1016/0378-4347(95)00202-T
- Description: An accurate, sensitive, selective and reproducible high-performance liquid chromatographic method with coulometric detection for the determination of cyclizine and its inactive demethylated metabolite, norcyclizine, in biological fluids has been developed. The drugs were separated using a custom packed reversed-phase C18 analytical column and phosphate buffer (0.05 M, pH 3)-acetonitrile (7:3) as mobile phase. The dual electrode coulometric detector was operated in the "oxidative-screen" mode with the upstream electrode (detector 1) set at 0.55 V and the downstream electrode (detector 2) set at 0.90 V. Serum and urine samples were prepared for analysis by solid-phase extraction, followed by a simple phase-separation step. The limit of quantitation was 1 ng/ml for both cyclizine and norcyclizine in serum and urine.
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- Date Issued: 1995
Southern African Journal of Gerontology, volume 4, number 1, April 1995
- Authors: Ferreira, Monica (editor) , Møller, Valerie (editor) , HSRC/UCT Centre for Gerontology
- Date: 1995
- Subjects: Gerontology -- South Africa , Older people -- Care -- South Africa
- Language: English
- Type: Text
- Identifier: vital:8070 , http://hdl.handle.net/10962/d1012862
- Description: [From Editorial]The sixth number of SA. IG includes varied and interesting contributions which will appeal to researchers and practitioners alike. It is fitting that precisely a year after the first fully democratic elections were held in South Africa. an article by M0ller on voter education of older Africans should be included in this number. M0ller has captured the euphoria of the older first-time voters in her selection of quotations from media reports on the voting. She concludes in her article that for these older South Africans who waited over 40 years to be enfranchised, voting was experienced as a particularly fulfilling moment in their lives. In an original paper Burman examines the findings of a study on the nature and extent of child care rendered by older coloured women in the Cape Peninsula - either to grandchildren. or to the children of other relatives or non-relatives. Burman considers the economic implications of the care which the women provide and finds that very few benefit financially. On the contrary, she notes a downward, rather than an expected upward flow of wealth, whereby social old-age pensioners share their pension money with other members of the household, including the grandchildren for whom they care. Burman concludes that not only are intergenerational relations strengthened by older women remaining in the family structure and caring for young children but through their pensions they enjoy considerable status in the household. Three practice items are included in this number. Working within a social-work framework, Howes has developed a monitoring instrument for use in the case management of older clients in the community. She reviews recent literature on case management and introduces the concept to South African practitioners, indicating its potential usefulness in a restructured service-delivery system in South Africa. She argues that to address the backlog in service delivery in developing and rural communities. and in view of limited resources and other reasons which discourage institutional care. case management is a means of rendering and co-ordinating cost-effective care to older persons in the community. , Authors Amosun, Mazarire and Mawere examine the pattern of utilization of physiotherapy services by elderly Zimbabweans at a central hospital in Harare. They establish baseline data on the medical conditions for which the patients received physiotherapy. The authors highlight the need for adequate information in these areas in African countries. In the third practice item, Tooke raises the issue of developing and providing training for carers in homes for the aged. He reports on the training methodology which he has developed for this category of worker, and calls for the setting of standards for such training and the institution of procedures to ensure that standardized training of carers is carried out in homes. The poor training of carers. or a lack of training for this cadre of workers has been mooted as a factor which contributes to the mis-treatment or abuse of residents in homes (Conradie & Charlton. 1992 ). Historically, South African nursing bodies have not recognized these workers and have opposed formal training that might equip them to perform tasks done by student nurses (enrolled nursing auxiliaries). In post-election South Africa new cadres of workers increasingly need to be trained and employed. as part and parcel of the goals of the Reconstruction and Development Programme (RDP). which includes not only training citizens but also creating work and career opportunities for all. To ascertain the present attitudes of national nursing bodies towards the training of carers. the South African Nursing Council and the South African Nursing Association were invited to reply to the proposals in Dr Tooke's brief. Their replies are published as rejoinders to the brief. Finally, this number of SAJG also carries its first book review. Valerie Moller reviews the new publication of US authors Steven M. Albert and Maria G. Cattell. titled Old age in global perspective: cross-cultural and cross-national views. The book, which adopts a multidisciplinary approach, presents ethnographic case studies and evidence from cross-national surveys to assess variation in the experience of ageing and old age. Møller concludes that Southern African readers will gain many insights from the book, to better understand the complexities of ageing in their own society.
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- Date Issued: 1995
Southern African Journal of Gerontology, volume 4, number 2, October 1995
- Authors: Ferreira, Monica (editor) , Moller, Valerie , HSRC/UCT Centre for Gerontology
- Date: 1995
- Subjects: Gerontology -- South Africa , Older people -- Care -- South Africa
- Language: English
- Type: Text
- Identifier: vital:8071 , http://hdl.handle.net/10962/d1012864
- Description: This special issue of SAJG on "The family and ageing in Africa" marks yet another step in the annals of the African Gerontological Society (AGES). The first major step was taken in December 1993 when the society held its first workshop in Accra, Ghana to discuss an agenda on ageing. The results of the workshop were published under the title Effective responses to ageing in Africa by the year 2000 (Apt, Bester & Insley, 1995). Twenty years ago it would have been an impossible task to assemble African scientists and social welfare practitioners to discuss the subject of ageing. Very little researched information existed then and many African governments were likely to assert that ageing was no problem in their country. Even in the 1980s a great deal of scepticism existed in Africa about the need for African gerontology research. Today, and taking a cue from the deliberations of the first AGES workshop, there is no country in our region that is not confronted with the negative impacts of development and urbanization as their country charts its route towards modernization. Even though an ageing agenda still has a low profile on the economic desks of many African governments, the realisation that there are indeed difficulties to be overcome regarding the care of elderly people in Africa is widespread.
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- Date Issued: 1995
Staff development policy
- Authors: Chemical Workers Industrial Union (CWIU)
- Date: 1995
- Subjects: CWIU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/170184 , vital:41866
- Description: CWIU is committed to the development of all its staff members. Therefore all staff members will have the opportunity to further their skills and. education supported by the Union. 1.1. The primary objective is to ensure that the aims and objectives of the union are achieved through an efficient,effective and excellent staff; 1.2. In addition,the union believes that individual staff members should have the opportunity to realise their full potential; Therefore,in implementing a Staff Development policy a balance will be achieved between organisational needs,which are primary,and personal needs of staff members.
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- Date Issued: 1995
Staffing committee meeting report
- Authors: Chemical Workers Industrial Union (CWIU)
- Date: 1995
- Subjects: CWIU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/170205 , vital:41868
- Full Text:
- Date Issued: 1995
Strategic plan for the restructuring of the textile and clothing industries
- Authors: SACTWU
- Date: 1995
- Subjects: SACTWU
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/176444 , vital:42695
- Description: The achievement of international competitiveness within a 10 year time frame with: a minimisation of the loss of job opportunities in the textile industry, the growth and net creation of jobs in the clothing sector, both formal and informal, successful, in general, export-orientated textile and clothing industries, the acceptance by the industries of a greater responsibility for their own future by lessening their dependence on government by improving productivity through human resource development, work organisation and upgraded technology; a conscious move out of the lower end of the market but simultaneous efforts to retain these activities within the region; and a competitive environment where everyone gains, including the consumer, by making basic goods more affordable.
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- Date Issued: 1995
Structural studies on the capsular antigens of some Escherichia coli serotypes
- Authors: Leslie, Margaret Ruth
- Date: 1995
- Subjects: Escherichia Polysaccharides Antigens Enterobacteriaceae
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:3767 , http://hdl.handle.net/10962/d1003245
- Description: The research presented in this thesis forms part of an on-going collaborative programme concerned with the determination of the chemical structures of the surface antigens of bacteria belonging to genera within the family Enterobacteriaceae. Bacteria of this family are opportunistic pathogens and are frequently responsible for serious infections in animals and man. Surface antigens produced by virulent strains are largely polysaccharides and occur as lipopolysaccharides (the O-antigens) and capsular polysaccharides (the K-antigens) respectively. The extracellular polysaccharide antigens expressed by strains of the species Escherichia coli are of considerable . interest due to their effect on immunological processes and the relationship which exists between their chemical structure and virulence. To date, some seventy-four K-antigens have been distinguished serologically within the species E. coli and structures have been determined for most of these. The K-antigens of E. coli are structurally diverse and exhibit serological cross-reactivity with other pathogenic bacteria. The structures of five previously unstudied E. coli K-antigens, viz. those produced by serotypes 020:K1 01 :H-, 08:K45:H9, 08:K50:H-, 0101 :K1 03:H-, and 08:K43:H11, are presented in this thesis. A variety of chemical techniques has been employed in the structural analysis, and these are discussed. Two-dimensional NMR spectroscopic techniques proved invaluable for the structural elucidation of these complex carbohydrates, and high-field NMR spectroscopy alone was used in the analysis of the K43 antigen. Structural analysis of the K1 03 antigen was facilitated by specific enzymatic degradation, using a bacteriophage-borne endoglycanase. The K45 antigen was found to contain the unusual sugar 3-acetamido-3,6-dideoxygalactopyranose, while the K50 and K103 antigens join a minority group of polysaccharides which contain pyruvate as their only acidic component.
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- Date Issued: 1995
Synthetic and spectrometric studies of benzodioxepinone derivatives
- Authors: Gelebe, Aifheli Carlson
- Date: 1995
- Subjects: Benzodiazepines -- Research Flavonoids -- Research
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:4382 , http://hdl.handle.net/10962/d1005047
- Description: An extensive range of oxygen and sulphur substituted benzodiazepine analogues has been synthesised via Baeyer-Villiger and Schmidt reactions of specially prepared flavanone and N-acetyl-4-quinolone precursors. Alternative, cyclisation routes have also been used to prepare some of these compounds. Ring-opening reactions of 1,5-benzodioxepinones have been investigated and a detailed kinetic-mechanistic study of the Baeyer-Villiger reaction of flavanones has been carried out using 1 H NMR spectroscopy to explain the observed regiochemistry of oxygen insertion. The electron-impact mass spectrometric fragmentation patterns of series of 4-aryl-l ,5-benzoxathiepinones, 3-aryl-4, I-benzoxathiepinones and 3-aryl-4,1-benzoxathiepines have been studied using a combination of low-resolution, highresolution and metastable-peak analyses. The 170 NMR spectroscopic properties of various oxygenated analogues have also been studied. The binding affinities of selected benzodiazepine analogues for rat brain benzodiazepine receptors have been evaluated using a radioreceptor assay technique; at certain concentrations, some of test compounds exhibited remarkable potentiation of diazepam binding, others the ability to displace diazepam from benzodiazepine receptors. A conformational analysis of the 7-membered ring systems has been undertaken, using lH NMR spectroscopic, computer modelling and x-ray crystallographic techniques, and certain conformational preferences have been identified.
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- Date Issued: 1995
The analysis of a computer music network and the implementation of essential subsystems
- Authors: Wilks, Antony John
- Date: 1995
- Subjects: Computer networks , Computer music , MIDI (Standard)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4666 , http://hdl.handle.net/10962/d1006682 , Computer networks , Computer music , MIDI (Standard)
- Description: The inability to share resources in commercial and institutional computer music studios results in non-optimal resource utilisation. The use of computers to process, store and communicate data can be extended within these studios, to provide the capability of sharing resources amongst their users. This thesis describes a computer music network which was designed for this purpose. Certain devices had to be custom built for the implementation of the network. The thesis discusses the design and construction of these devices.
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- Date Issued: 1995
The Children of Pierrette
- Authors: Mamou Sidibe (composer, author, lead singer) , MALI K7 S.A. Ali Furka Toure Associe, Bamako
- Date: 1995
- Subjects: Popular music--Africa, West , Blues (Music) , Africa Mali Bamako f-ml
- Language: Khassonke
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/129949 , vital:36349 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC35-04
- Description: Khassonke blues from the Khassonke region of western Mali, performed with guitar, calabash, percussion and voice
- Full Text: false
- Date Issued: 1995
The Children of Pierrette
- Authors: Mamou Sidibe (composer, author, lead singer) , MALI K7 S.A. Ali Furka Toure Associe, Bamako
- Date: 1995
- Subjects: Popular music--Africa, West , Blues (Music) , Africa Mali Bamako f-ml
- Language: Khassonke
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/129937 , vital:36348 , International Library of African Music, Rhodes University, Grahamstown, South Africa , SDC35-04
- Description: Khassonke blues from the Khassonke region of western Mali, performed with guitar, calabash, percussion and voice
- Full Text: false
- Date Issued: 1995
The collapse of the 'tribal authority' system and the rise of civic organisations
- Authors: Manona, Cecil Wele , Paper presented at an ISER Seminar, March 1995
- Date: 1995
- Subjects: Civic associations -- South Africa Local government -- South Africa -- Ciskei Local government -- South Africa Tribal government -- South Africa
- Language: English
- Type: Manuscript , Text
- Identifier: http://hdl.handle.net/10962/2454 , vital:20293
- Description: The paper examines the performance of a local ('tribal') authority which existed in the Keiskammahoek district up to 1993 and accounts for the rise of civic organisations which challenged tribal authorities virtually everywhere in the former Ciskei. It suggests that the problems of this local authority which included inefficiency, corruption and lack of democracy were manifestations of the limitations of the Black Authorities Act of 1951 which attempted to revive traditional authority in the rural areas in south Africa even though this was incompatible with political developments in many other African states, particularly in a period during which the process of decolonisation was at its peak. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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- Date Issued: 1995
The conflict between adaptation and constraint : the case of the Siphonariid limpets
- Authors: Chambers, Richard Jonathan
- Date: 1995
- Subjects: Siphonaria -- Adaptation Limpets -- Adaptation Pulmonata
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: vital:5657 , http://hdl.handle.net/10962/d1005340
- Description: The reproductive strategies of marine invertebrates have been related to various aspects of both their ecology, and their phylogenetic history. It has been the purpose of this thesis to try and separate these components among Siphonaria, a group of marine pulmonates. The taxonomy of these species is revised and I conclude that nine species are valid. All species deposit benthic egg masses and development may be either direct (S. anneae, S. compressa, S. dayi, S. nigerrima, S. serrata and S. tenuicostulata) or planktonic (S. capensis, S.concinna and S. oculus). Data on distribution and life-history relating to mode of larval development is then presented for 26 species of Siphonaria worldwide. Fifteen species are direct developers, nine are planktonic developers and a further two appear to have a dual developmental capacity, retaining both the velar swimming apparatus of a planktonic developer and the crawling foot of a direct developer. Direct developing species hatch from larger egg capsules, and generally occur higher on the shore than planktonic developers. Worldwide, planktonic developers are more widespread than direct developers, and individual planktonic species may have a greater latitudinal range. In most S~honaria subgenera, mode of larval development appears to be constant, although two subgenera (Patel/opsis and Sacculosiphonaria) include both developmental types. Locally, the intertidal zonation of three sympatric species (S. capensis, S. concinna and S. serrata) does not support a model which predicts direct development on the high shore and planktonic development on the low shore. However, distributions do correspond to particular intertidal microhabitats, and while there may be no, direct relationship between mode of larval development and intertidal height, the physical structure of egg masses, and the microhabitats used for spawning appear adaptive with regards to desiccation in the intertidal. S. concinna (planktonic development) and S. serrata (direct development) occur in similar microhabitats and are likely to be under similar selection pressures. In having different modes of larval development, there appears to be more than one optimal solution in a particular selective regime. In addition, both species seem to apportion similar amounts of energy to reproduction for each spawning episode, and also annually suggesting an optimum allocation of resources to reproduction. Genetic investigations using PolyAcrylamide Gel Electrophoresis (PAGE) confirm the status of the southern African species initially described, and indicate greater genetic variability associated with planktonic developing species than direct developing species. The systematic relationships revealed by DNA fingerprinting support the current classification systems, and also have implications with regards the evolution of larval development: direct development may be the plesiomorphic condition in, and among, some Siphonaria groups. There are both phylogenetic and adaptive explanations for the distribution of reproductive mode among benthic marine invertebrates. An evolutionary question, however, is not just a matter of either adaptation or constraint, it is a combination of these. Both contribute to the distribution of developmental mode among Siphonaria.
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- Date Issued: 1995
The development of a typology of science teachers' views on the nature of science and science practical work: an evaluative pilot study
- Authors: Meiring, Leslie Frank
- Date: 1995
- Subjects: Science -- Study and teaching -- Research Science -- Study and teaching -- South Africa Science teachers -- Attitudes Science -- Philosoph
- Language: English
- Type: Thesis , Masters , MEd
- Identifier: vital:1931 , http://hdl.handle.net/10962/d1007607
- Description: Many theories on the nature of science and the nature of learning have been proposed. In particular, two theoretical orientations have been identified as having a decisive impact on activities in the school science classroom, namely "Inductivism" and "Constructivism". Inductivism views observations as objective, facts as constants and knowledge as being obtained from a fixed external reality. The constructivist view sees all knowledge as "reality" reconstructed in the mind of the learner. Each view predisposes certain orientations towards the science curriculum and within it particularly to assessment. It is postulated that teachers' views on science will influence how they teach and assess it. An "inductivist" teacher is more likely to reward certain approved responses from learners whereas a "constructivist" teacher is more likely to attend to learners' unique observations as evidence of their thinking. In this study a questionnaire was developed in an attempt classify science teachers according to their views on the nature of science and learning, and during this process encourage them to reflect on these views. It is hoped that the instrument could measure any changes in teacher's views as a result of the teachers becoming more reflective practitioners over time. Research indicates that the majority of teachers have a predominantly inductivist view of science. The study confirmed the results of other researchers by showing that a majority of non-tertiary science educators could be classified as being strongly inductivist. However, the overall proportion of these teachers was not as high as expected. Of possible concern was the indication that the strongly constructivist group showed very strong inductivist tendencies when assessing written tests which involved pupils' responses to laboratory observations.
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- Date Issued: 1995
The discourse of postgraduate seminars
- Authors: De Klerk, Vivian A
- Date: 1995
- Language: English
- Type: Article
- Identifier: vital:6132 , http://hdl.handle.net/10962/d1011584
- Description: Video recordings of a range of postgraduate seminars in the Arts Faculty at a South African university were made and analyzed, in order to define the current nature of this particular form of educational practice in South African tertiary institutions. Recent demographic changes in formerly White universities are having a significant effect on the nature of interaction in formal discussion groups. Despite a common perception that at a tertiary level tutors and students are equally entitled to speak and all contributions equally valued, this article reveals that postgraduate seminars are sites of competition for the floor and that there are significant imbalances in participation by different groups in this competitive speaking environment; it is further argued that these imbalances reflect different (culture- and gender-specific) assumptions about what constitutes appropriate participation and also, to some degree, previous learned discourse patterns associated with schooling experience.
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- Date Issued: 1995
The effect of fluctuating substrate salinity on the yield and flag leaf photosynthesis of wheat
- Authors: Beckett, R P , Drennan, P M , Botha, Christiaan E J
- Date: 1995
- Language: English
- Type: Article
- Identifier: vital:6501 , http://hdl.handle.net/10962/d1005922
- Description: The effects of constant and fluctuating substrate salinity on flag leaf photosynthesis and grain yield of wheat were investigated. Plants exposed to salinity fluctuating around a mean integrated value of 25 mol m-3 NaCl (0-50 mol m-3) and around 50 mol m-3 NaCl (25-75 mol m-3) had yields 36 and 38% higher, respectively, than those receiving the corresponding constant salinity. Plants treated with salinity fluctuating from 50-100 mol m-3 NaCl had a 14% lower yield than those receiving 75 mol m-3 NaCl. Flag leaf photosynthesis did not vary between treatments and during salinity fluctuations, suggesting that differences in flag leaf longevity caused the observed differences in yield. Results suggest plants grown under constant salinity are unlikely to behave as those in field situations, where fluctuating rather than constant salinity occurs.
- Full Text: false
- Date Issued: 1995