title: Special section on human development as a critical voice in education: Editor's introduction

authors: Claiborne, Lise Bird

subjects: social development

abstract: An introduction is presented in which the editor discusses various reports within the issue on topics including human development, the importance of economic context for young people, children's perspectives within school governance.

text: Special section on human development as a critical voice in education: Editor's introduction An introduction is presented in which the editor discusses various reports within the issue on topics including human development, the importance of economic context for young people, children's perspectives within school governance.

year: 2011

title: Development of immunoaffinity columns and immunoassays for the collection, partial purification and measurement of sporidesmin A and its metabolites

authors: Briggs, Lyn R.

abstract: Monoclonal and polyclonal antibodies were produced for the development of competitive enzyme-linked immunosorbent assays (cELISA) for sporidesmin A, the mycotoxin that causes facial eczema in grazing livestock. Derivatives of sporidesmin conjugated to a number of proteins were used as immunising antigens and plate-coating antigens for cELISA. Two immunoassays, each detecting the presence of a different region of the sporidesmin A molecule have been developed. They allow the two major sporidesmins found in grass or in Pithomyces chartarum cultures to be distinguished. Organic solvent extraction of samples was avoided so that water-soluble metabolites could also be detected.

To assist in the selection of animals resistant to facial eczema, the cELISAs were applied to a study of the metabolism of sporidesmin A in sheep. The cELISAs distinguish between sporidesmin A and its metabolites, as one antibody detects only sporidesmin A and the other detects sporidesmin A and metabolites. After sheep were dosed with sporidesmin A it was possible to monitor the excretion of the toxin in bile and its metabolite(s) in both bile and urine using the appropriate cELISA. There were no differences between resistant and susceptible sheep in the cumulative totals or excretion rates of immunoreactive metabolite in animals dosed with sporidesmin A.

The detection of sporidesmin metabolites in sheep urine by cELISA was shown to have potential as a biomarker for measuring exposure to toxic pastures which could give early warning of the risk of facial eczema.

An immunoaffinity chromatography matrix was prepared by coupling antibody to cyanogen bromide-activated Sepharose. The matrix bound sporidesmin A and immunoreactive metabolites from urine, and bound analytes were eluted with 40% methanol in water. The matrix capacity for sporidesmin A was 900 ng of sporidesmin A bound per mL of matrix, and for sporidesmin metabolites from urine it was approximately 500 ng of sporidesmin A immunoreactive equivalents per mL of matrix.

A method was developed for the preparation of milk for immunoaffinity chromatography so that blocking of columns by milk fats was avoided. Sample concentration obtained using the immunoaffinity chromatography lowered the limit of quantification for the previously developed cELISA for sporidesmin A in milk by a factor of 100.

A trial was carried out to determine whether sporidesmin residues appeared in milk following experimental ingestion of the toxin. Using the cELISA, sporidesmin metabolites were detected in milk samples collected after dosing. Further evidence for the presence of immunoreactive material was obtained by using immunoaffinity chromatography to recover the material from milk. Positive results in the sporidesmin A specific cELISA suggest the presence of free sporidesmin A at picogram levels. Purification from a much larger sample, and analyses by HPLC and mass spectrometry are needed to confirm this result.

It should now be possible to use the anti-sporidesmin antibodies in immunochemical technologies and formats which are suitable for on-farm use. These could be used to help minimise exposure to sporidesmin A and provide an important advance in animal health.

text: Development of immunoaffinity columns and immunoassays for the collection, partial purification and measurement of sporidesmin A and its metabolites Monoclonal and polyclonal antibodies were produced for the development of competitive enzyme-linked immunosorbent assays (cELISA) for sporidesmin A, the mycotoxin that causes facial eczema in grazing livestock. Derivatives of sporidesmin conjugated to a number of proteins were used as immunising antigens and plate-coating antigens for cELISA. Two immunoassays, each detecting the presence of a different region of the sporidesmin A molecule have been developed. They allow the two major sporidesmins found in grass or in Pithomyces chartarum cultures to be distinguished. Organic solvent extraction of samples was avoided so that water-soluble metabolites could also be detected.

To assist in the selection of animals resistant to facial eczema, the cELISAs were applied to a study of the metabolism of sporidesmin A in sheep. The cELISAs distinguish between sporidesmin A and its metabolites, as one antibody detects only sporidesmin A and the other detects sporidesmin A and metabolites. After sheep were dosed with sporidesmin A it was possible to monitor the excretion of the toxin in bile and its metabolite(s) in both bile and urine using the appropriate cELISA. There were no differences between resistant and susceptible sheep in the cumulative totals or excretion rates of immunoreactive metabolite in animals dosed with sporidesmin A.

The detection of sporidesmin metabolites in sheep urine by cELISA was shown to have potential as a biomarker for measuring exposure to toxic pastures which could give early warning of the risk of facial eczema.

An immunoaffinity chromatography matrix was prepared by coupling antibody to cyanogen bromide-activated Sepharose. The matrix bound sporidesmin A and immunoreactive metabolites from urine, and bound analytes were eluted with 40% methanol in water. The matrix capacity for sporidesmin A was 900 ng of sporidesmin A bound per mL of matrix, and for sporidesmin metabolites from urine it was approximately 500 ng of sporidesmin A immunoreactive equivalents per mL of matrix.

A method was developed for the preparation of milk for immunoaffinity chromatography so that blocking of columns by milk fats was avoided. Sample concentration obtained using the immunoaffinity chromatography lowered the limit of quantification for the previously developed cELISA for sporidesmin A in milk by a factor of 100.

A trial was carried out to determine whether sporidesmin residues appeared in milk following experimental ingestion of the toxin. Using the cELISA, sporidesmin metabolites were detected in milk samples collected after dosing. Further evidence for the presence of immunoreactive material was obtained by using immunoaffinity chromatography to recover the material from milk. Positive results in the sporidesmin A specific cELISA suggest the presence of free sporidesmin A at picogram levels. Purification from a much larger sample, and analyses by HPLC and mass spectrometry are needed to confirm this result.

It should now be possible to use the anti-sporidesmin antibodies in immunochemical technologies and formats which are suitable for on-farm use. These could be used to help minimise exposure to sporidesmin A and provide an important advance in animal health.

year: 1997

title: Bringing home the body: Bi/multi racial Maori women's hybridity in Aotearoa/New Zealand

authors: Moeke-Maxwell, Tess

abstract: This thesis examines the exclusion of bi/multi racial Maori women from dominant representations of Maori women's identity. As such, it engages with a new articulation of Maori women's difference through a narrative of cultural hybridity. Presented in two parts, Part One engages with a theoretical overview of the formation of the New Zealand nation, the social construction of Maori and Pakeha cultural groups and the race relations that developed through the discursive practices of colonialism Through a study of key texts on the history of New Zealand and dominant articulations describing Maori nationalists' efforts to invoke equality for New Zealand's indigenous people during the 1970s - 1980s, I exemplify how an essentialist Maori women's identity was promoted within Maori nationalist appeals to bicultural nationalism This textual research indicates that an exclusive and traditional narrative of Maori women's identity emerged to exclude the specificities of bi/multi racial Maori women. As such, their experiences are ignored within dominant academic, feminist and Maori articulations of what constitutes Maori women's cultural identity. Current articulations of Maori women's identity do not include an analysis of race, gender and class, nor the way they operate simultaneously to position the bi/multi racial woman discursively in the nation today. 
In order to extend a narrative of Maori women's identity to include bi/multi racial women, Part Two engages with a qualitative research methodology. The social construction and 'performance' of Maori women's cultural hybridity is identified. Twenty women who position themselves as bi/multi racial were interviewed using a 'Kaupapa Bi/multi Racial Research' methodology, which was developed using a feminist oriented 'life-history' approach, sensitised to Maori research cultural specificities. Interviews allowed the participants' unique experiences to emerge, permitting an examination of Maori women's cultural hybridity. These narratives, when grounded in the theoretical ideas outlined in Part One, provide the experiential evidence needed to support an articulation of bi/multi racial identity. My research insists that the raced and gendered body must be reinstated within articulations of Maori women's identity through situating corporeal difference within discussions on their subjectivity and related marginalisation. Until then, the materiality of the raced and gendered body will remain detached and suspended from bi/multi racial women's cultural and material existence.

text: Bringing home the body: Bi/multi racial Maori women's hybridity in Aotearoa/New Zealand This thesis examines the exclusion of bi/multi racial Maori women from dominant representations of Maori women's identity. As such, it engages with a new articulation of Maori women's difference through a narrative of cultural hybridity. Presented in two parts, Part One engages with a theoretical overview of the formation of the New Zealand nation, the social construction of Maori and Pakeha cultural groups and the race relations that developed through the discursive practices of colonialism Through a study of key texts on the history of New Zealand and dominant articulations describing Maori nationalists' efforts to invoke equality for New Zealand's indigenous people during the 1970s - 1980s, I exemplify how an essentialist Maori women's identity was promoted within Maori nationalist appeals to bicultural nationalism This textual research indicates that an exclusive and traditional narrative of Maori women's identity emerged to exclude the specificities of bi/multi racial Maori women. As such, their experiences are ignored within dominant academic, feminist and Maori articulations of what constitutes Maori women's cultural identity. Current articulations of Maori women's identity do not include an analysis of race, gender and class, nor the way they operate simultaneously to position the bi/multi racial woman discursively in the nation today. 
In order to extend a narrative of Maori women's identity to include bi/multi racial women, Part Two engages with a qualitative research methodology. The social construction and 'performance' of Maori women's cultural hybridity is identified. Twenty women who position themselves as bi/multi racial were interviewed using a 'Kaupapa Bi/multi Racial Research' methodology, which was developed using a feminist oriented 'life-history' approach, sensitised to Maori research cultural specificities. Interviews allowed the participants' unique experiences to emerge, permitting an examination of Maori women's cultural hybridity. These narratives, when grounded in the theoretical ideas outlined in Part One, provide the experiential evidence needed to support an articulation of bi/multi racial identity. My research insists that the raced and gendered body must be reinstated within articulations of Maori women's identity through situating corporeal difference within discussions on their subjectivity and related marginalisation. Until then, the materiality of the raced and gendered body will remain detached and suspended from bi/multi racial women's cultural and material existence.

year: 2003