Interactions between ants, herbivorous insects and bracken (Pteridium aquilinum), a fern with extrafloral nectaries
- Authors: Rashbrook, Vanessa Karin
- Date: 1989
- Subjects: Arthropod pests -- South Africa Ants -- South Africa Ferns -- South Africa
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5592 , http://hdl.handle.net/10962/d1002042
- Description: Bracken (Pteridium aquilinum) is a cosmopolitan species of fern which possesses extrafloral nectaries. A survey of the arthropod fauna associated with the plant throughout its range in South Africa identified the most widespread and damaging bracken herbivores and those species most likely to be influenced by ants visiting the extrafloral nectaries. Seventeen herbivorous arthropods were found to be definitely feeding on bracken and a further thirteen species with a less certain status were recorded. In addition, several species of ants were observed on the fronds and feeding at the extrafloral nectarie. On the basis of their widespread distribution and abundance, four bracken herbivores emerged as being particularly detrimental to the plant in South Africa. They were an eriophyid gall mite, a leafhopper and two moths. The biology of the two lepidopterans, Appana cinisigna and Panotima sp., suggested that they were potentially vulnerable to ants at various stages of their life histories. Laboratory experiments were undertaken to observe ant-lepidopteran interactions under controlled conditions. The ant Crematogaster peringueyi rapidly removed exposed A. cini igna eggs, but did not appear to regard Panotima eggs as food items. Small instar larvae of both species proved vulnerable, but the larger larvae appeared capable of escaping ant predation. Ant exclusion experiments in the field, using natural and artificially augmented ant densities, were carried out at two sites near Grahamstown. The dominant ant species was C. peringueyi. Neither the numbers of lepidopterans nor levels of herbivory were significantly reduced by the presence of ants . Despite the implications of the laboratory tests, the results of these field experiments did not support the hypothesis that ants which visit bracken extrafloral nectaries benefit the plant. Ant-bracken field studies on other continents also reported no significant ant-related effects, though marginal reductions in the abundance of certain herbivores have been noted at one site in the U.K. Since ant protection does not appear to be an inevitable consequence of having extrafloral nectaries, their value to bracken is in some doubt. The most likely situation where effective protection will occur is when high densities of vulnerable herbivores are preyed upon by large numbers of aggressive ants. However, even under these conditions, enhancement of plant fitness is not inevitable. This raises the question of why extrafloral nectaries have been retained in a plant that is as successful and widespread as bracken.
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- Date Issued: 1989
Investigation of the causative agents of the 1982 Gazankulu poliomyelitis outbreak, using four biochemical techniques
- Authors: Gibson, Katherine Margaret
- Date: 1989
- Subjects: Poliomyelitis -- Analysis , Poliomyelitis -- History -- South Africa , Poliomyelitis vaccine -- Analysis
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:3878 , http://hdl.handle.net/10962/d1001612
- Description: Comparison of poliovirus strains was carried out to determine the origin of the virus in two isolates obtained during the 1982 outbreak of poliomyelitis in Gazankulu. Comparisons of the outbreak isolates with vaccine and wild-type strains of the same poliovirus type were carried out using four biochemical techniques. SDS-polyacrylamide gel electrophoresis (SDS-PAGE), two-dimensional thin-layer chromatography (TLC) and reversed-phase high-performance liquid-chromatography (RP-HPLC) were used for comparing viral capsid proteins. Comparison of poliovirus strains at a genetic level was carried out using two-dimensional oligonucleotide mapping of viral RNA. Results showed the type 1 poliovirus isolate, 5061, to be a novel wild-type poliovirus. The type 2 isolate, 5068, was closely related to the poliovirus type 2 Sabin vaccine strain, P712. It was concluded that the intrinsic variability of poliovirus strains was responsible for the appearance of isolate 5068
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- Date Issued: 1989
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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- Date Issued: 1989
It's a long way to go to heaven
- Authors: Sacred Music Festival Participants , Composer Not Specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/316175 , vital:59797 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD137-30
- Description: Unaccompanied Music Festival Performance.
- Full Text: false
- Date Issued: 1989
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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- Date Issued: 1989
Jesus is coming over and over
- Authors: Sacred Music Festival Participants , Composer Not Specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/316134 , vital:59792 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD137-25
- Description: Unaccompanied Music Festival Performance.
- Full Text: false
- Date Issued: 1989
Konyana Ya Modimo
- Authors: Sacred Music Festival Participants , Composer Not Specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/315112 , vital:59678 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD136-48
- Description: Music Festival Performance with clapping accompaniment.
- Full Text: false
- Date Issued: 1989
Kyrie
- Authors: Sacred Music Festival Participants , Composer not specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/314655 , vital:59624 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD136-02
- Description: Unaccompanied Music Festival Performance.
- Full Text: false
- Date Issued: 1989
Let it Be
- Authors: Sacred Music Festival Participants , Composer Not Specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/315103 , vital:59677 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD136-47
- Description: Music Festival Performance with clapping accompaniment.
- Full Text: false
- Date Issued: 1989
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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- Date Issued: 1989
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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- Date Issued: 1989
Morena Re Utlwele Botlhoko
- Authors: Sacred Music Festival Participants , Composer not specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/314665 , vital:59626 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD136-03
- Description: Unaccompanied Music Festival Performance.
- Full Text: false
- Date Issued: 1989
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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- Date Issued: 1989
My Jesus
- Authors: Sacred Music Festival Participants , Composer Not Specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/315284 , vital:59697 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD136-63
- Description: Unaccompanied Music Festival Performance.
- Full Text: false
- Date Issued: 1989
Nesting of sympatric redwinged and pale winged starlings
- Authors: Craig, Adrian J F K , Hulley, Patrick E , Walter, Grenville H
- Date: 1989
- Subjects: To be catalogued
- Language: English
- Type: text , article
- Identifier: http://hdl.handle.net/10962/447827 , vital:74677 , https://doi.org/10.1080/00306525.1989.9634513
- Description: Observations were made over four breeding seasons at Cradock, South Africa, where Redwinged Starlings Onychognathus morio and Palewinged Starlings O. nabouroup nest on the same cliffs. Nests were not accessible, and the stage of breeding was determined by the behaviour of the birds. Both species reuse the same nest sites, and only the females incubate, but both sexes feed the young. The timing of breedingMaybe more variable in the Palewinged Starling. A review of the available data on nest site selection and nest construction shows apparent species-specific differences: Redwinged Starlings usually nest on ledges, often on buildings, and use mud in the nest base; Palewinged Starlings favour vertical crevices, and do not use mud.
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- Date Issued: 1989
Never Give Up
- Authors: Sacred Music Festival Participants , Composer not specified , Dargie, Dave
- Date: 1989
- Subjects: Folk music , Field recordings , Africa, Sub-Saharan , Africa South Africa Ga-Rankuwa f-sa
- Language: English
- Type: sound recordings , field recordings , sound recording-musical
- Identifier: http://hdl.handle.net/10962/314768 , vital:59636 , International Library of African Music, Rhodes University, Makhanda, South Africa , Dave Dargie Field Tapes, Rhodes University, Makhanda, South Africa , DD136-12
- Description: Unaccompanied Music Festival Performance.
- Full Text: false
- Date Issued: 1989
New species and new records of rare Antarctic Paraliparis fishes (Scorpaeniformes: Liparididae)
- Authors: Stein, David, L , Tompkins, Linda, S
- Date: 1989
- Subjects: Cyclopteridae -- Antarctica , Paraliparis -- Antarctica
- Language: English
- Type: Text
- Identifier: vital:14997 , http://hdl.handle.net/10962/d1019703 , Ichthyological Bulletin of the J.L.B. Smith Institute of Ichthyology; No. 53
- Description: The liparidid fishes collected in the Southern Ocean by the U.S. Navy vessel “Eltanin” were reviewed in an unpublished M.Sc. thesis by the junior author (Tompkins, 1977). These collections include several hundred specimens, of which 134, representing at least 10 species of the genus Paraliparis, have been re-examined by the senior author and are the subject of the present paper. Descriptions are given for five new species of Antarctic Paraliparis: P. anarthractae, P. andriashevi, P. eltanini, P. incognita, and P. fuscolingua. Four of the new species are illustrated; the fifth (P. incognita) was illustrated by Andriashev (1986: Fig. 59) as P. terraenovae Regan, 1916. P. edentatus Andriashev, 1986 is synonymized with P. terraenovae, and additional data on this species are presented. A probable new species of Paraliparis is diagnosed but not named due to the poor condition of the single specimen. New records of five other rare species (P. antarcticus Regan P. devriesi Andriashev, P. meganchus Andriashev, P. stehmanni Andriashev, and P. tetrapteryx Andriashev) are discussed. , Rhodes University Libraries (Digitisation)
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- Date Issued: 1989
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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- Date Issued: 1989
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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- Date Issued: 1989
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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- Date Issued: 1989