List of Titles

Water hyacinth, Eichhornia crassipes (Pontederiaceae), reduces benthic macroinvertebrate diversity in a protected subtropical lake in South Africa

- Coetzee, Julie A, Jones, Roy W, Hill, Martin P

Authors: Coetzee, Julie A , Jones, Roy W , Hill, Martin P
Date: 2012
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/479023 , vital:78252 , https://doi.org/10.1007/s10531-014-0667-9
Description: The socio-economic impacts of the free-floating aquatic plant water hyacinth, Eichhornia crassipes (Pontederiaceae), on aquatic systems are well documented, yet the impacts on aquatic biodiversity, particularly invertebrate biodiversity, are less well understood. This study aimed to determine whether the presence of water hyacinth altered the diversity and assemblage structure of benthic macroinvertebrates in a conservation area. The benthic macroinvertebrate assemblage was sampled over 1 year at five sites under water hyacinth mats and at five sites without water hyacinth at Lake Nsezi—Nseleni River in the vicinity of Richards Bay, KwaZulu-Natal, South Africa. Artificial substrates were placed beneath water hyacinth mats or in the open water to allow for colonization by freshwater macroinvertebrates, and left for a period of 6 weeks, repeated on seven occasions. Twenty nine families comprising 18,797 individuals were collected, 817 (13 families) individuals were from under water hyacinth mat sites compared to 17,980 (27 families) individuals from open water sites.
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Water quality dynamics in an experimental serial-use raceway and its effects on growth of South African abalone, Haliotis midae

- Naylor, Matthew Aubrey

Authors: Naylor, Matthew Aubrey
Date: 2012
Subjects: Haliotis midae -- South Africa , Abalone culture -- South Africa , Abalones -- Effect of water quality on , Abalones -- Nutrition -- South Africa , Abalones -- Feeding and feeds , Abalones -- Growth , Fish culture -- Water reuse
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:5335 , http://hdl.handle.net/10962/d1005181 , Haliotis midae -- South Africa , Abalone culture -- South Africa , Abalones -- Effect of water quality on , Abalones -- Nutrition -- South Africa , Abalones -- Feeding and feeds , Abalones -- Growth , Fish culture -- Water reuse
Description: An understanding of species specific water quality requirements is essential for efficient production of aquaculture products, an aspect not well documented for the land-based culture of the South African abalone, Haliotis midae. In order for the industry to remain competitive in international markets, efficient use of water supplies and the development of water reuse technology is needed. This study assessed the changes in water quality between tanks in a tiered serial-use raceway in relation to accumulated biomass and water flow and estimated the flow index (FI) (L h⁻¹ kg⁻¹) at which growth becomes significantly affected. The effect of dietary protein level, supplementation of pure oxygen and addition of sodium hydroxide (NaOH⁻) on water quality and fundamental production parameters in the serial-use raceways was also assessed. The serial-use raceways were used as a tool to create a range of water quality conditions at which the growth, feed conversion ratio (FCR) and condition factor (CF) of "cocktail" size (60 – 70 mm) H. midae could be monitored. The metabolic activity of the abalone resulted in a deterioration in water quality between tanks in series. pH (r² = 0.99; p < 0.001) and dissolved oxygen concentration (r² = 0.99; p < 0.001) were positively correlated with flow index (pH = 7.38 FI°·°² ; dissolved oxygen = 6.92 FI°·°⁴), while free ammonia nitrogen (FAN) (r² = 0.99, p < 0.001) and nitrite (NO²⁻ - N) (r² = 0.93, p < 0.001) were negatively correlated with flow index (FAN = 8.02 FI⁻°·⁷¹). Nitrite concentrations increased over time indicating colonisation of Nitrosomonas bacteria on the basket surfaces. A flow index of 7.2 – 9.0 L h⁻¹ kg⁻¹ was estimated as the minimum to avoid significant reductions in weight and shell length gain and increases in FCR values. Total ammonia nitrogen (TAN) and FAN concentrations were significantly correlated to dietary protein (P) (t = 6.63, p < 0.0001 and t = 6.41, p < 0.0001, respectively) and flow index (t = 5.42, p < 0.0001 and t = 3.9, p < 0.0002, respectively) and could be estimated using the models TAN = 9.73 P – 110.3 log (FI), and FAN = 0.132 P – 1.10 log (FI). Mean FAN concentrations were 67 and 41 % lower in tanks fed a diet containing 22 and 26 % protein respectively, when compared to tanks fed a 33 % protein diet. Supplementation with pure oxygen (103 ± 8 % saturation) improved shell length gain (t = 3.45, p = 0.026) in abalone exposed to high FAN (2.43 ± 1.1 μg L⁻¹) and low pH (7.6 ± 0.13), relative to a treatment with no oxygen supplementation (92 ± 6 % saturation). Addition of a sodium hydroxide solution resulted in elevated mean pH in treatment raceways when compared to control raceways. The increased pH resulted in significantly higher weight gain (g abalone⁻¹) (F₁·₁₂ = 4.51; p = 0.055) and shell length gain (mm abalone⁻¹) (F₁·₁₂ = 4.56; p = 0.054) at an α-error level of < 5.5 %. In two trials, weight gain and shell length gain were significantly correlated to pH (p < 0.001), and multiple regression of pH, dissolved oxygen and FAN consistently revealed pH to be the best predictor of growth. It is therefore suggested that decreasing pH is the first limiting water quality variable for abalone in serial-use raceways. As a decrease in water pH is linked to respiration by the abalone and subsequent increase in dissolved carbon dioxide (CO₂) concentration, future studies should examine the effects of CO₂ on H. midae metabolic rate, calcification rate and health. The results of this study will contribute toward our understanding of the specific water quality requirements for H. midae in commercial aquaculture systems, and influence the design and management procedures for abalone water reuse systems.
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Web-based visualisation techniques for reporting zoonotic outbreaks

- Ncube, Sinini Paul

Authors: Ncube, Sinini Paul
Date: 2012
Subjects: Zoonoses -- Reporting , Communicable diseases -- Reporting , Communication in medicine , Medical telematics , Internet , Information visualization
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4664 , http://hdl.handle.net/10962/d1006672 , Zoonoses -- Reporting , Communicable diseases -- Reporting , Communication in medicine , Medical telematics , Internet , Information visualization
Description: Zoonotic diseases are diseases that are transmitted from animals or vectors to humans and vice versa. The public together with veterinarian authorities should readily access disease information as it is vital in rapidly controlling resultant zoonotic outbreak threats through improved awareness. Currently, the reporting of disease information in South Africa is predominantly limited to traditional methods of Information Communication Technologies (ICTs) like faxes, monthly newspaper reports, radios, phones and televisions. Although these are effective ways of communication, their disadvantage is that the information that most of them offer can only be accessed at specific times during a crisis. New technologies like the internet have become the most efficient way of distributing information in near-real-time. Many developed countries have used web-based reporting platforms to deliver timely information through temporal and geographic visualisation techniques. There has been an attempt in the use of web-based reporting in South Africa but most of these sites are characterised by heavy text which makes them time consuming to use or maintain. As a result most sites have not been updated or have ceased to exist because of the work load involved. The success of web reporting mechanisms in developed countries offers evidence that web-based reporting systems when appropriately visualised can improve the easy understanding of information and efficiency in the analysis of that data. In this thesis, a web-based reporting prototype was proposed after gathering information from different sources: literature related to disease reporting and the visualisation of infectious diseases; the exploration of the currently deployed web systems; and the investigation of user requirements from relevant parties. The proposed prototype system was then developed using Adobe Flash tools, Java and MySQL languages. A focus group then reviewed the developed system to ascertain that the relevant requirements had been incorporated and to obtain additional ideas about the system. This led to the proposal of a new prototype system that can be used by the authorities concerned as a plan to develop a fully functional disease reporting system for South Africa.
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Welcome Address of the Vice‐Chancellor of Rhodes University, Dr Saleem Badat, to First‐Year students

- Badat, Saleem

Authors: Badat, Saleem
Date: 2012
Language: English
Type: text
Identifier: vital:7592 , http://hdl.handle.net/10962/d1006583
Description: From introduction: Our first purpose is to produce knowledge, so that we can better understand our natural and social worlds and also enrich our scientific and cultural heritage. The second purpose of a university is to disseminate knowledge and to develop critical and creative minds. Our goals, yours and ours, must be for you to think imaginatively, ‘effectively and critically;’ to ‘achieve depth in some field of knowledge;’ to appreciate how we ‘gain knowledge and understanding of the universe, of society, and of ourselves;’ to have ‘a broad knowledge of other cultures and other times;’ to critique ideas and views and construct alternatives, and to communicate cogently, orally and in writing. Our final purpose as a university is to undertake community engagement, whether this is as part of academic courses or your voluntary participation in community projects organized by our Community Engagement Office.
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What's been built in twenty years?: SADC and Southern Africa's political and regional security culture

- Bischoff, Paul, 1954-

Authors: Bischoff, Paul, 1954-
Date: 2012
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/161498 , vital:40633
Description: The sense of region in Southern Africa is based on nationalism and its struggles for national liberation. Unusually, the norms of smaller states initially shaped the region's scope and culture of interaction. First and foremost, cooperation happened in the area of security, an initial focus being to uphold the independence and sovereignty of the state in the face of challenges from apartheid South Africa. As such, rather atypically, intergovernmental security cooperation preceded broad based economic cooperation. This has meant that security and development have remained largely de-linked and this has helped discourage implementing a society or human rights centred approach to security. Cooperation has been made more difficult by disparate political systems with divergent values, cultures, agendas and sensibilities. As such, regionalism reinforces nationalism to the exclusion of development or wider notions of political and social security. The region amounts to a security regime with only a patchy record in advancing security. Therefore, in the face of developmental challenges and unless a degree of strategic coherence along political and policy fronts is reached, after 20 years of SADC the endeavour to institutionalise security in conventional state-centred ways amounts to a scenario of diminishing returns.
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Where angels fear to tread: online peer-assessment in a large first-year class

- Mostert, Markus, Snowball, Jeanette D

Authors: Mostert, Markus , Snowball, Jeanette D
Date: 2012
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/69289 , vital:29480 , https://doi.org/10.1080/02602938.2012.683770
Description: In the context of widening participation, large classes and increased diversity, assessment of student learning is becoming increasingly problematic in that providing formative feedback aimed at developing student writing proves to be particularly laborious. Although the potential value of peer assessment has been well documented in the literature, the associated administrative burden, also in relation to managing anonymity and intellectual ownership, makes this option less attractive, particularly in large classes. A potential solution involves the use of information and communication technologies to automate the logistics associated with peer assessment in a time-efficient way. However, uptake of such systems in the higher education community is limited, and research in this area is only beginning. This case study reports on the use of the Moodle Workshop module for formative peer assessment of students’ individual work in a first-year introductory macro-economics class of over 800 students. Data were collected through an end-of-course evaluation survey of students. The study found that using the feature-rich Workshop module not only addressed many of the practical challenges associated with paper-based peer assessments, but also provided a range of additional options for enhancing validity and reliability of peer assessments that would not be possible with paper-based systems.
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White anti-racism in post-apartheid South Africa:

- Matthews, Sally

Authors: Matthews, Sally
Date: 2012
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/142361 , vital:38073 , DOI: 10.1080/02589346.2012.683938
Description: South Africans today live not only with the memory of the racial injustices of the past, but also with present injustices that are a consequence of that past. How should white South Africans live with these past and present injustices? On recognition of the racial injustices of the past and of the continuation of forms of white privilege today, involvement in ongoing anti-racist struggles seems to be an appropriate way for white South Africans to respond to past and present injustices. However, some discussions of the way in which white privilege operates and is perpetuated in post-segregationist societies suggest the need for caution with regard to white involvement in anti-racist struggles, arguing that some of the ways in which white people involve themselves in apparently anti-racist work actually result in the perpetuation rather than the erosion of white privilege. This article explores concerns about the intractability of white privilege while also ultimately defending the appropriateness of white involvement in anti-racist struggles.
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Why do learners and teachers experience problems with the concept of zero?

- Jooste, Zonia

Authors: Jooste, Zonia
Date: 2012
Subjects: Numbers, Divisibility of -- Study and teaching (Primary) -- South Africa Numbers, Divisibility of -- Study and teaching (Secondary) -- South Africa Mathematics teachers -- Training of -- South Africa -- Eastern Cape Mathematics teachers -- Training of -- South Africa -- Western Cape Education, Primary -- Curricula -- South Africa Education, Secondary -- Curricula -- South Africa
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1906 , http://hdl.handle.net/10962/d1006764
Description: The controversy around the inclusion of zero in the number system has been widely documented. Influential mathematicians in various ancient cultures did not accept zero as a number. The idea of the empty set was too abstract and they could not conceptualise division by zero. Surprisingly, understanding of the concept is still a matter of concern today. In spite of expansive reports on and recommendations for developing conceptualisation of the concept, learners and teachers still experience problems similar to those that ancient mathematicians struggled with. The study was initiated by an observation of Grade 7 learners' inability to solve the problems 4 × 0 and 0 ÷ 7 effectively or at all. I investigated why Grade 3 to 6 learners and mathematics teachers on a BEd (in-service) course and an accredited ACE course experience problems with the concept of zero. I was especially interested in the understanding of multiplication and division by zero. I investigated teachers' knowledge of zero's characteristics as a number, the history of zero and how they teach the concept, in order to support my assumptions. The data production process was performed over a period of two years. It involved a multi-case opportunity sample approach embedded in the empirical field that formed the backdrop of my involvement as mathematics education specialist in schools in the Western and Eastern Cape. The interpretative orientation of the study allowed me to conduct inquiries that served to confirm or challenge my assumptions and enabled me to construct generalisations that depict learners' and teachers' knowledge construction. The qualitative data analysis informed the presentation and discussion of the findings. The single most important message conveyed to readers of this study is that the value of zero as a number, its importance in the number system, its properties and its behaviour in calculations, should not be underrated. Teaching of this abstract concept requires competent teachers who are able to mediate understanding in the most effective and innovative manner. Professional development programmes should orchestrate this competence and curriculum developers and textbook authors should acknowledge the significance of learning and teaching the concept of zero.
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Wing moult and sexual dimorphism in the Lesser Honeyguide Indicator minor in the Eastern Cape, South Africa

- Craig, Adrian J F K, Bonnevie, Bo T, Hulley, Patrick E

Authors: Craig, Adrian J F K , Bonnevie, Bo T , Hulley, Patrick E
Date: 2012
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/449593 , vital:74832 , https://www.tandfonline.com/doi/pdf/10.2989/00306525.2012.662918
Description: Based on ringing data from the Western Cape, Underhill et al.(1995) demonstrated that there was a bimodal distribution of wing-length measurements in the Lesser Honeyguide Indicator minor, and they described the timing of wing-moult in this region. Hanmer (1997) reported similar results for Lesser Honeyguides from Mozambique and Malawi. This species remains poorly studied, and we have examined size dimorphism and wing moult for a sample of birds from the Eastern Cape region: 44 museum specimens from the Albany Museum (Grahamstown), East London Museum and the Ditsong Museum (formerly Transvaal Museum, Pretoria), together with ringing data for 94 birds. Wing-length of both museum specimens and ringed birds was measured in the standard manner (maximum chord); weight to the nearest 0.5 g was recorded with a Pesola spring balance. Each bird was checked for wing moult, which was recorded as 0 for an old feather and 5 for a fully grown new feather (de Beer et al. 2001). These moult scores were converted to percentage feather mass grown using a primary feather mass index, Passer9 (Bonnevie 2010a), for analysis using the model of Underhill and Zucchini (1988), as implemented in R (Erni et al. in press), with the data subsampled to prevent non-moulting birds from biasing the estimates (Bonnevie 2010b).
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Women leadership: a case study in the Otjozondjupa Region, Namibia

- Araes, Cornelia

Authors: Araes, Cornelia
Date: 2012
Subjects: Women -- Education (Primary) -- Namibia Leadership in women -- Education (Primary) -- Namibia Management -- Education (Primary) -- Namibia Educational leadership -- Namibia
Language: English
Type: Thesis , Masters , MEd
Identifier: vital:1825 , http://hdl.handle.net/10962/d1003711
Description: Empowerment of women in leadership and in particular, school leadership has been the focus of the Namibian government and the country since independence in 1990. Different policies and laws, post‐independence, make provision for women empowerment and leadership in a range of organisations and institutions throughout the country. However, reports on gender equity in leadership positions suggest that Namibia is not really moving towards these policy goals at a sufficiently quick pace. A lot still needs to be achieved in terms of transforming the gender stereotyping in Namibia, which still suffers from the legacy of gender discrimination of the apartheid era. Modern‐day academic authors and journalists portray an increasing interest in an awareness of the advantages of women leadership. Women are increasingly perceived to have leadership styles more suitable for contemporary conditions than men. It is against this backdrop that this study sought to investigate women leadership in the Otjiwarongo circuit in the Otjozondjupa educational region in Namibia. The study used a qualitative, interpretive research paradigm. It adopted a case study approach. The primary participants consisted of four women principals in the Otjiwarongo circuit and the secondary participants included four women education officers from the same circuit. Semi‐structured interviews, a focus group interview and observation were applied as methods for collecting data and the data collection period was just over six weeks. Data analysis was done through coding and identification of categories. The findings revealed that women principals possessed the qualities of commitment, good communication and are passionate about their work, which are qualities normally associated with effective leadership. In terms of their role in their schools, they emerged as democratic leaders who involved all stakeholders in the decision making process through consensus. In addition, they demonstrated distributive and servant leadership in their interactions with stakeholders. The main challenge to the leadership position of these women principals seemed to be the stereotypical view held, that as women, they had to work twice as hard as men at leading schools. The study recommended that people oriented leadership styles, such as the ones enacted by the women principals in this study, are highly recommended for effective leadership in the 21st century.
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Working with cultural-historical activity theory and critical realism to investigate and expand farmer learning in Southern Africa

- Mukute, Mutizwa, Lotz-Sisitka, Heila

Authors: Mukute, Mutizwa , Lotz-Sisitka, Heila
Date: 2012
Subjects: To be catalogued
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/182494 , vital:43835 , xlink:href="https://doi.org/10.1080/10749039.2012.656173"
Description: This article uses the theoretical and methodological tools of cultural historical activity theory and critical realism to examine three case studies of the introduction and expansion of sustainable agricultural practices in southern Africa. The article addresses relevant issues in the field of agricultural extension, which lacks a theoretical “bridge” between top-down knowledge transfer and bottom-up participatory approaches to learning. Further, the article considers the learning environments necessary for sustainable agriculture. Such environments provided research participants with encounters with “postnormal” scientific practices that recognise and engage plural ways of knowing. Our research explored why farmers learn and practise sustainable agriculture, how they learn and practise it, the contradictions they are facing, and how these contradictions can be overcome in a context of change-oriented learning.
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Young veterans, not always social misfits: a sociological discourse of Liberian transmogrification experiences

- Agbedahin, Komlan

Authors: Agbedahin, Komlan
Date: 2012
Subjects: Child soldiers -- Liberia Children and war -- Liberia Liberia. Armed Forces -- Demobilization -- Social aspects Liberia -- History -- Civil War, 1989-1996 Liberia -- History -- Civil War, 1999-2003
Language: English
Type: Thesis , Doctoral , PhD
Identifier: vital:3316 , http://hdl.handle.net/10962/d1003104
Description: This thesis examines the phenomenon of child-soldiering from a different perspective. It seeks to challenge, using a novel approach, earlier studies on the roles of former child-soldiers in post-war societies. It focuses on the subjectivity of young veterans, that is war veterans formerly associated with armed forces and groups as children during the 14-year gruesome civil war which bedevilled Liberia between 1989 and 2003. This civil war claimed roughly 250,000 lives, and saw the active participation of approximately 21,000 child-soldiers. This thesis departs from previous works which mostly painted an apocalyptic picture of young veterans, and explores the nexus between their self-agency, Foucauldian technologies of the self and their transformation in the post-war society. The majority of previous scholarly works which have dominated the field of child-soldiering dwelt on the impact of armed conflict on the child-soldiers, the negative consequences, the causes of child-soldiering, and the rehabilitation and reintegration of the young veterans after their disarmament and demobilization. What this thesis seeks to do however, is to establish that, rather than considering the young veterans simply as social misfits, distraught and dispirited human beings, it should be noted that young veterans through their agency, are capable of ensuring their reintegration into their war-ravaged societies. Sadly, these young former fighters’ self-agency and technologies of the self in defining their civilian trajectories have often been overshadowed by vaunted humanitarian aid and multilayered war-profiteering. This study is underpinned by interpretive constructivism, symbolic interactionism, social identity theory, sociometer theory and expectancy theory, and sheds light on how young veterans’ self-agency, instrumental coalitions, and decision-making processes, synergistically shifted the negative identities foisted on them as a result of their participation in the war.
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μCloud : a P2P cloud platform for computing service provision

- Fouodji Tasse, Ghislain

Authors: Fouodji Tasse, Ghislain
Date: 2012 , 2012-08-22
Subjects: Cloud computing , Peer-to-peer architecture (Computer networks) , Computer architecture , Computer service industry
Language: English
Type: Thesis , Masters , MSc
Identifier: vital:4663 , http://hdl.handle.net/10962/d1006669 , Cloud computing , Peer-to-peer architecture (Computer networks) , Computer architecture , Computer service industry
Description: The advancements in virtualization technologies have provided a large spectrum of computational approaches. Dedicated computations can be run on private environments (virtual machines), created within the same computer. Through capable APIs, this functionality is leveraged for the service we wish to implement; a computer power service (CPS). We target peer-to-peer systems for this service, to exploit the potential of aggregating computing resources. The concept of a P2P network is mostly known for its expanded usage in distributed networks for sharing resources like content files or real-time data. This study adds computing power to the list of shared resources by describing a suitable service composition. Taking into account the dynamic nature of the platform, this CPS provision is achieved using a self stabilizing clustering algorithm. So, the resulting system of our research is based around a hierarchical P2P architecture and offers end-to-end consideration of resource provisioning and reliability. We named this system μCloud and characterizes it as a self-provisioning cloud service platform. It is designed, implemented and presented in this dissertation. Eventually, we assessed our work by showing that μCloud succeeds in providing user-centric services using a P2P computing unit. With this, we conclude that our system would be highly beneficial in both small and massively deployed environments. , KMBT_223 , Adobe Acrobat 9.51 Paper Capture Plug-in
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Shaking a hornets' nest: pitfalls of abortion counselling in a secular constitutional order–a view from South Africa

- Vincent, Louise

Authors: Vincent, Louise
Date: 2011
Language: English
Type: text , article
Identifier: http://hdl.handle.net/10962/141521 , vital:37982 , DOI: 10.1080/13691058.2011.627469
Description: There exists an enormous gulf between the aspirations of South Africa's abortion legislation – among the most liberal in the world – and its implementation. One weakness in the provision of abortion services in South Africa is the absence of comprehensive abortion counselling services. On the face of it, the idea that counselling ought, as a matter of course, to be a significant component of a country's termination of pregnancy service provision, seems both straightforwardly sensible and politically innocent. This paper describes how abortion counselling has historically, in many different contexts, been saturated with questionable assumptions about women and their bodies. Counselling has more often than not been deployed, either as the formal policy of states or through informal mechanisms, as a means of curbing the right to abortion rather than deepening the meaning of that right. Differing approaches to counselling emerge as a reflection of contestations over reproductive and gender politics. Specifying an appropriate model for the provision of state-sponsored abortion counselling in the public health sector of a secular constitutional state provokes more of a hornet's nest of dilemmas than is sometimes supposed.
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