Isolation, purification and effect of ligands on the nicotinic cholinergic receptor
- Authors: Kapp, Eugene Anthony
- Date: 1989
- Subjects: Ligands (Biochemistry) , Nicotinic receptors
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4550 , http://hdl.handle.net/10962/d1018235
- Description: The nicotinic cholinergic receptor protein of the fish electric organ, Torpedo fuscomaculata, has been isolated, purified and shown to represent a true model for the nAChR from other species and higher vertebrates. It is an integral membrane protein composed of four different subunits, tightly associated with other functional, but non-specific proteins. Purification of the nicotinic cholinergic receptor by chromatofocusing demonstrates an improved method over that of affinity and ion-exchange chromatography. Gel chromatography and SDS-polyacrylamide gel electrophoresis show evidence of four subunits; a(40-44 kDa), 6(53 kDa ),'Y(63 kDa) and 6(66 kDa) despite some degradation of receptor molecules by intracellular proteases. Spectrophotometric and fluorimetric studies of receptor-ligand interactions, show the functional and chemical integrity of the receptor to remain intact after solubilisation. The effect of cholinergic ligands on purified receptor preparations indicate quenching of the intrinsic fluorescence of the receptor. Agonists, like acetylcholine, bind and cause local conformational transitions, changing the active region from a hydrophobic to a hydrophilic environment. This phenomenon is illustrated by the 10-fold increase in fluorescence when the receptor is in a desensitised state. Antagonists, such as d-Tubocurarine, block this conformational transition. In vitro rectus abdominis muscle preparations . show the nitrosamines, dimethylnitrosamine and diphenylnitrosamine, to be true agonists of the nAChR. However their low affinity and specificity for the receptor precludes them as photoaffmity labelling agents. Photoactivation of dimethylnitrosamine occurs when associated with an acidic hydrogen at the active site of the receptor, suggesting energy-transfer labelling to be more facile than photoaffmity labelling. The membrane-bound receptor, in the presence of these nitrosamines, undergoes conformational transitions regulating the opening and closing of the ion-channel. Desensitisation and receptor activation are shown to involve one and the same molecular transition.
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Jean Dubuffet : a study of his concepts pertaining to the alienation of the artist
- Authors: Mather-Pike, Richard
- Date: 1989
- Language: English
- Type: Thesis , Masters , MFA
- Identifier: vital:21086 , http://hdl.handle.net/10962/6290
- Description: I decided on an investigation into the nature of Dubuffet's remarks concerning the plight of the artist in modern societies, believing that the difficulties facing the artist are, at the time of this writing, still in force, and perhaps even more so now than they were in his day. These difficulties I believe, arise in the form of curtailments on personal and aesthetic freedoms brought about as the result of the artist's position in, and conformity to, the norms and values of his society. The problem is I believe, that these value systems not only censor or curb artistic freedom but actually restrict all individual enterprises by demanding that the indi vidual conform to the greater wish of the group, at the expense of his own creative and individual potential.
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Local government restructuring : white municipal initiatives 1985-1988
- Authors: Atkinson, Doreen
- Date: 1989
- Subjects: Local government -- South Africa Municipal government -- South Africa
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/d1011618 , vital:20235 , ISBN 0868101826
- Description: The local government level has historically been the most neglected aspect of government in South Africa, both in research and in conventional political activity. Yet, paradoxically, it has been the level at which several crucial government policies have played themselves out, away from the public eye, but drastic in their effects on the material and political position of all inhabitants of towns and cities in South Africa. This research into local government was begun with two basic questions in mind. Firstly, local-level attempts to alter their own institutional structures needed to be documented and analysed. A consideration of six case studies of white initiatives for change at the local level uncovered numerous political and economic dimensions which interact and set constraints on each other. It is impossible to produce one final interpretation of why these local events happened, what their significance was, and what possibilities they offer for the future. Invariably, each case study is a microcosm of the broader multifaceted conflict in South Africa. This report is an attempt to present as many of these dimensions as possible, even though it cannot ever be complete. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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Medical schemes for workers
- Authors: Trade Union Research Project (TURP)
- Date: 1989
- Subjects: TURP
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/169044 , vital:41678
- Description: Medical insurance schemes have become one of 111 the many fringe benefits being negotiated by unions. Medical insurance schemes are tied to the struggle for an adequate health service. Workers’ decision on whether or not to join medical insurance schemes has an important bearing on the operation of health services in a future democratic society. This booklet examines medical aid schemes, their advantages and disadvantages, how they operate and what possible alternatives to medical aid schemes exist. The booklet also looks at the state’s health strategy and how medical aid schemes fit into this. Chapter One of this booklet discusses the broad issues relating to medical insurance. Medical Aid Schemes and Medical Benefit Schemes are discussed in chapters two and three. Chapters four and five are for extra information. Some specific medical aid schemes are evaluated in chapter four. Chapter five looks at the tariff structure (cost) of medical services provided at Natal Provincial Hospitals. Medical Insurance means all the different types of schemes that operate to insure people against medical costs. A medical insurance could take the form of a medical aid scheme, a medical benefit scheme or other types of schemes. This-booklet concentrates on medical aid and medical benefit schemes.
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Mother-son enmeshment and its implications for the emancipation-individuation process: a case study study
- Authors: Gijana, Eucliffe Wycliffe Mphumzi
- Date: 1989
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:21173 , http://hdl.handle.net/10962/6728
- Description: This case study reports on a patient who was undergoing psychotherapy for an Adjustment Disorder with Mixed Emotional Features. The aim of the study had two aspects. First the study sought to establish to what degree was enmeshment between the patient and his mother responsible for his maladaptive behaviour. The second aspect was to establish the extent to which the patient responded to psychotherapy. The patient was a 20 year old male university student. He was experiencing a number of problems including difficulty in interpersonal relations, deteriorating academic performance, depression, anxiety and uncertainty about career choice and about the future. The history revealed that the patient had very close and enmeshed relations with his mother. The mother was a very domineering person and had great influence on her son. On the other hand his father was weak and emotionally unavailable. The patient had never been away from home until after he graduated from High School and decided to join the army. It was then his problem began to manifest. He left the army and registered at university. However, the problems continued and even increased in intensity. It was hypothesized that as a result of enmeshment with his mother and the fact that his mother was a domineering personality, he never had the opportunity to learn social skills that would have enabled him to emancipate himself from his mother . Thus when he moved out of home to be on his own, first in the army and later at university, he could not cope. He lost self-confidence, became passive, indecisive and dependent. Psychotherapy was successful in helping him gain insight into the genesis of his problem. This insight resulted in the patient's efforts towards individuation.
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NUM Biennial report
- Authors: NUM
- Date: 1989
- Subjects: NUM
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/149589 , vital:38866
- Description: Since the Fifth National Congress in 1987 where our union adopted the Freedom Charter and charted a clear political direction for the NUM, many gallant battles have been waged by the mineworkers on many fronts. 1987 was the year in which our union launched its campaign to effect control of miners working lives. It was a year when mineworkers took control indeed in keeping with the Fifth Congress Slogan -"1987 THE YEAR MINEWORKERS TAKE CONTROL", as many comrades began to take over the hostels, particularly in the Witbank Region which resulted in families moving into the hostels for a period of time. Although the process remained uneven, the initiative was an important indicator of the willingness of the workers to take action and implement resolutions adopted by our union. In spite of the existence of the State of Emergency, the dedication, commitment, spirit and enthusiasm of mineworkers remained high. 1987 was also the year in which the NUM made its mark on the mining industry with the historic Great Miners Strike. This action, involving over 340 000 workers was the biggest of its kind in South African Labour History, and also the biggest action by workers of its kind on the African continent. We challenged some of the fundamental policies of the mining industry, in particular, the concept of poverty wages which has become one of the major battle grounds for our union. Despite mass dismissals of 50 000 workers, our union has remained and continues to mobilise and organise mineworkers against the oppressive and exploitative conditions. 1987 will certainly go down in history as the year of mass action by mineworkers throughout South Africa. It is well known that the strike did affect our organisation in many areas. Actions by management to roll back the gains of our union continued unabated after the strike right through until now.
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Obedient daughter, silenced witch: the hysteric in Freudian psychoanalysis
- Authors: Roux, Catharina
- Date: 1989
- Subjects: Freud, Sigmund, 1856-1939 -- Criticism and interpretation , Hysteria , Psychoanalysis , Seduction
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:3117 , http://hdl.handle.net/10962/d1004637 , Freud, Sigmund, 1856-1939 -- Criticism and interpretation , Hysteria , Psychoanalysis , Seduction
- Description: This study explores the theoretical consequences of Freud's renunciation of the seduction theory. The dissertation defends the thesis that the seduction theory was shaped as much by Freud's adherence to the nomonological model as by the empirical evidence of child sexual abuse. A renunciation of the seduction theory was inevitable, not because the accounts of the daughters were lies, but because the methodology was inappropriate. The nomonological model obscured the emotional structure of the nuclear family in which the structure itself, through which sexuality emerged, directed the girl's entrance into womanhood and caused the woman's dis-ease. Freud's methodology forced him to isolate an event as cause of an illness and to attribute the event to an agent. The universal perversity of the Victorian father thus became the central theme around which an explanation of a female disease was built. When this theme became theoretically untenable, Freud renounced the seduction theory and, still using the nomonological model, built up the construct of the Oedipus complex in which the father was vindicated. In order to exonerate the father, the transactions through which the child's libido developed were represented as originating in inherent tendencies. As a result, the hierarchical nature of the interaction between parent and child was distorted, and this led to the formulation of the distinction between real events and fantasies as a basic premise on which the difference between the pleasure principle and the reality principle rests. This formulation gave rise to the sharp duality between fantasy and reality which eventually compelled him to separate psychic reality and social reality. The theoretical structure built on this duality could not but fuse hysteria, masochism and "normal" femininity into an explanation of the female state, and obscure the essential social relations between men and women which were structured in terms of dominance and submission. The thesis traces the journey from the perverted father as cause of a female disease, hysteria, to the theoretical conjunction of masochism and hysteria. It comes to the conclusion that Freud's model is unable to explain the self-mutilation of the hysteric; nor is it capable of explaining the hysteric's refusal to participate in the circuit of symbolic exchanges which constituted Victorian society. The study further attempts to understand hysteria in terms of the complex interlacing of fact and fantasy and tries to show that fantasy was rooted in the facts of Victorian culture.
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Opening our eyes
- Authors: Cape Educational Computer Society (CECS)
- Date: 1989
- Subjects: Cape Educational Computer Society (CECS)
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/250511 , vital:52008
- Description: This is a bold statement and a difficult one for people who regard] computers as a tool of the rich. Yes the computer is a tool or the rich. But more and more of these weird little machines are finding their way into our backyards and ghettos, into the backrooms of our community organisations and even into our classrooms. Each of these computers can do what only the rich with million rand typographic equipment could do 10 years ago . Today ordinary people can bring out media of a quality that only highly trained professionals using specialised equipment used to be able to produce. This edition of CECS NEWS is proof of this. Almost the entire newsletter was produced by High School student members of CECS trained on a 5-day camp in June. “Computers For All” is not just an empty slogan but a possible reality. We decided at the camp to devote an entire issue to just this topic: Media on Computers.
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Operating in turbulent times: an investigation into the characteristics of strategic flexibility exhibited by South African export companies
- Authors: Skae, Frederick Owen
- Date: 1989
- Subjects: Export trading companies -- South Africa
- Language: English
- Type: Thesis , Masters , MCom
- Identifier: vital:1159 , http://hdl.handle.net/10962/d1001626
- Description: Broadly stated, the major objective of this study was to investigate the extent to which South African export companies exhibited characteristics of strategic flexibility, which is seen to be the most viable strategic option for a firm operating within a turbulent environment. This entailed:- (1) Determining the degree of environmental turbulence as perceived by South African export companies and identifying the most important elements of the external environment as perceived by these companies. (2) Identifying the nature and strength of the various components of strategic flexibility possessed by South African export companies facing environments of either low, medium or high turbulence. (3) Identifying the nature and strength of the various components of strategic flexibility possessed by South African export companies of different size. In order to elicit this information, 1361 questionnaires were posted to the managing directors of export firms who were members of the South African Foreign Trade Organization. The major findings of this study indicate that:- (1) Political elements of the remote environment contribute most to environmental turbulence. (2) Respondents identified economic elements as being the most important in terms of their potential impact on the long term profitability of the firm. (3) Although at present the majority of the firms surveyed were classified as operatIng in medium levels of turbulence, in the future they perceive the external environment as becoming very turbulent. (4) Generally speaking, the firms surveyed are ill-equipped to operate in a turbulent environment as they displayed signs of inflexibility in certain key aspects of their business. In this regard, particular mention must be made of their decision-making processes, the extent to which they had specialist planners, the techniques used to identify future trends in the environment, the extent to which computer technology was utilised in the firm and their structure. (5) Finally, the results do not generally support the view that a relationship exists between the perceived degree of turbulence in the environment and the extent to which strategic flexibility exists in the firm. Often, however, the size of tne firm was more of a determining factor on the components of strategic flexibility than the degree of turbulence in the environment. In this regard, particular mention must be made of the impact of size on the planning processes of the firm, the techniques used to monitor trends in the environment and the emphasis placed on management development and training.
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Oxygen isotope geochemistry of the Mesozoic volcanics of the Etendeka Formation, Namibia
- Authors: Harris, Chris , Smith, H Stuart , Milner, Simon C , Erlank, Anthony J , Duncan, Andrew R , Marsh, Julian S , Ikin, Nicholas P
- Date: 1989
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143272 , vital:38219 , https://doi.org/10.1007/BF00371087
- Description: The Etendeka Formation volcanics consist of a bimodal association of basalts and quartz latites. Forty three new whole rock oxygen isotope analyses are reported for all the major magma types. All the rocks except a minor suite of dolerites have higher δ18O values than normal mantle. The basic rocks (average of 29=8.8‰) have significantly different δ18O to the acid rocks (average of 10=14.4‰). These data are apparently consistent with previously published petrogenetic models, which propose that the basalts were affected by crustal contamination and that the quartz latites are crustally derived.
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Parallel process placement
- Authors: Handler, Caroline
- Date: 1989
- Subjects: Parallel programming (Computer science)
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:4568 , http://hdl.handle.net/10962/d1002033
- Description: This thesis investigates methods of automatic allocation of processes to available processors in a given network configuration. The research described covers the investigation of various algorithms for optimal process allocation. Among those researched were an algorithm which used a branch and bound technique, an algorithm based on graph theory, and an heuristic algorithm involving cluster analysis. These have been implemented and tested in conjunction with the gathering of performance statistics during program execution, for use in improving subsequent allocations. The system has been implemented on a network of loosely-coupled microcomputers using multi-port serial communication links to simulate a transputer network. The concurrent programming language occam has been implemented, replacing the explicit process allocation constructs with an automatic placement algorithm. This enables the source code to be completely separated from hardware considerations
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Part four of the Rhodes University Skymap Program
- Authors: Wright, Michael Robert
- Date: 1989
- Subjects: Southern sky (Astronomy) Radio astronomy
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5435 , http://hdl.handle.net/10962/d1001988
- Description: The results of the fourth part of the Rhodes University Skymap Program are presented. The observations cover the area of sky between right ascension 14h00m and 02h30m and declination -26⁰ and + 13⁰ at a frequency of 2.3 GHz. Contour maps of this region, with a resolution of 0.38⁰, are presented. Various methods of reducing the effect of the Galactic disc emission are analyzed. The results demonstrate the effectiveness of one of these methods in the production of a flat base level. The filamentary structure of the North Polar Spur is enhanced and results are obtained which support current theories of the origin of this object. The HII region surrounding Ophiuchi is examined in detail. A number of parameters are derived for the HII region. The spur associated with the HII region S54 is also examined. A listing of 1105 point sources appearing in the maps is presented. The limiting flux density of this listing is 0.5 Jy
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Physiological and psychophysical factors in the rating of perceived exertion during uphill overground and treadmill running
- Authors: Olivier, Stephen Chris
- Date: 1989
- Subjects: Physical fitness -- Measurement , Physical fitness -- Physiological aspects , Physical fitness -- Psychological aspects , Running -- Testing
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:5161 , http://hdl.handle.net/10962/d1015769
- Description: The purpose of this study was to examine possible differences between the field and laboratory ratings of perceived exertion (RPE) when the performance and physiological measures for the two conditions were equated. Furthermore, the interactive effects of local, central and overall RPE were examined. Finally, the question of the potential effects of attitudes on RPE was addressed. Eleven well-conditioned adult male marathon runners voluntarily participated in the study. After a period of treadmill habituation, biographical and anthropometric data were collected. This was followed by a VO₂ max test and a speed-matching session at 70% of VO₂ max to determine overground running speed at 3.8% and 7. 5% grade. Subjects then completed an attitudinal questionnaire and ran 4km overground. Finally, the above test was repeated on the treadmill, with the gradient and running speed of the overground condition being replicated. Physiological measures and differentiated RPE were obtained during the final two sessions. There were no physical environmental, task characteristic or performance differences between the overground and treadmill conditions. No heart rate or VO₂ differences were observed between the two conditions, but VE was significantly elevated in the laboratory. Local and overall RPE were significantly higher in the laboratory than in the field, but there was no difference for central RPE. Attitudes were more favourable towards the field than towards the laboratory work task. The results suggest that neither heart rate nor VO₂ are major factors directly influencing the perception of exertion. VE however appears to be a potent central signal mediating RPE. The results also indicate that local factors play a more important role in the perception of exertion than was previously thought. Attitudes towards a work task could possibly mediate the self-reports of exertion. The findings of this study also suggest that RPE are influenced by cognition to a large degree. Finally, environmental cues, or the ambience of a particular working environment, can exert a substantial influence on RPE. Direct perceptual translations from laboratory to field situations may therefore be invalid.
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Plants - yesterday, today, tomorrow? : inaugural lecture delivered at Rhodes University
- Authors: Botha, Christiaan Edward Johannes
- Date: 1989
- Subjects: Botany
- Language: English
- Type: Text
- Identifier: vital:603 , http://hdl.handle.net/10962/d1020672 , ISBN 0868101931
- Description: Inaugural lecture delivered at Rhodes University. , Rhodes University Libraries (Digitisation)
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POTWA Newsletter - Northern Cape Congress
- Authors: Post and Telecommunication Workers Association (POTWA)
- Date: 1989
- Subjects: POTWA
- Language: English
- Type: text
- Identifier: http://hdl.handle.net/10962/162032 , vital:40750
- Description: The Northern Cape Region of Potwa held a very vibrant regional congress in Vryburg on the 15 & 16 April 1989. The Congress was characterised by a spirit of comradely self-criticism. This political maturity of the comrades went as far as to give a proper critical analysis of the structures of our organisation. The analysis accepted that the functioning of some of our organisation’s structures is not up to standard. The congress also noted that the participation of the general membership in the activities of the organisation is not satisfactory. As it is typical of matured comrades, the congress realised that such problems are not peculiar to Potwa. Shortcomings such as these are indicative of a huge and growing organisation. Because of this, the comrades explored ways and means of solving these problems. The congress concluded that the opening of a regional office combined with effective usage of our Potwa newsletter would go a long way in solving some of our problems.
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Rainfall characteristics, rainfall reliability and the definition of drought : Baringo district, Kenya
- Authors: Rowntree, K M
- Date: 1989
- Language: English
- Type: Article
- Identifier: vital:6724 , http://hdl.handle.net/10962/d1006802
- Description: Monthly rainfall data for Kabarnet District Office, together with comments taken from the Baringo District Annual Report, are used here to examine the relationship between rainfall characteristics and agricultural drought experienced over the period 1915 to 1943 in order to establish the meteorological criteria for a definition of drought applicable to the former Kerio Native Land Unit, Baringo District, Kenya. The concept of reliable rainfall as a drought threshold is also examined. The analysis shows that the occurrence of drought was related to both the rainfall total and to the seasonal distribution. The meteorological criteria for drought and for reliable rainfall were found to differ between the upland cultivators and the lowland pastoralists, the latter experiencing a higher frequency of drought.
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Regional development administration and management in Region D
- Authors: Davies, William J
- Date: 1989
- Subjects: Regional planning -- South Africa -- Ciskei Regional planning -- South Africa -- Transkei Bathurst (South Africa) -- Population Transkei (South Africa) -- Economic conditions
- Language: English
- Type: Book , Text
- Identifier: http://hdl.handle.net/10962/2378 , vital:20283 , ISBN 0868101885
- Description: The process of managing and administering regional development in South Africa is in need of drastic revision. Exactly what form such revision takes, however, is not yet clear. The extent to which the structure and organisation of regional development programmes is intricately associated with the ideological principles of macro-apartheid is part of the problem and a great deal of work requires to be done in order to arrive at proposals which could constitute points of departure for constructing a new approach. This research is a small step in that direction and should be seen as a means to an end in an on-going process. , Digitised by Rhodes University Library on behalf of the Institute of Social and Economic Research (ISER)
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Rhodes University Graduation Ceremony 1989
- Authors: Rhodes University
- Date: 1989
- Language: English
- Type: text
- Identifier: vital:8123 , http://hdl.handle.net/10962/d1005706
- Description: Rhodes University Graduation Ceremonies on Friday, 7 April 1989 at 8 p.m. [and] on Saturday, 8 April 1989 at 10 a.m. in the 1820 Settlers National Monument. , Rhodes University East London Graduation Ceremony Saturday; 13 May 1989 at 11.30 a.m. in the Guild Theatre.
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Role of agricultural marketing in transforming subsistence agriculture: African Case Study
- Authors: Antrobus, Geoffrey G , Fraser, Gavin C G
- Date: 1989
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/143112 , vital:38202 , https://ageconsearch.umn.edu/record/197714/
- Description: A lack of agricultural marketing facilities is generally seen as one of the major obstacles to agricultural development. However, subsistence producers in southern Africa are influenced by certain exogeneous factors, such as competition from commercial production, the well-developed marketing system, and off-farm employment opportunities in South Africa. This paper studies the effect of the institution of an organized marketing system in Ciskei on the level of agricultural production. This is found to have had no significant effect because the majority of the able-bodied males are working in the metropolitan areas of South Africa. This has resulted in agriculture becoming a part-time supplementary activity for women, old men, and children in the rural areas.
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Satchitananda' : meditation and dance around the still point, in the form of a raga performance for piano solo : inaugural lecture/recital delivered at Rhodes University
- Authors: Nowotny, Norbert W
- Date: 1989
- Subjects: Music -- Instruction and study
- Language: English
- Type: Text
- Identifier: vital:656 , http://hdl.handle.net/10962/d1020725 , ISBN 0868101923
- Description: Inaugural lecture delivered at Rhodes University , Rhodes University Libraries (Digitisation)
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