title: Characterisation of Food Intake and Expression of Feeding-Related Genes in The VPA Rat Model of Autism Spectrum Disorder

authors: Laloli, Kathryn

subjects: Autism

abstract: Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting roughly 1% of the global population. Aberrant food selectivity (AFS) is a common comorbid symptom of ASD which can result in nutritional deficiencies, increased parental stress and reduced quality of life. However, alarmingly little research has been conducted investigating the nature and the underlying neurophysiological mechanisms of AFS in ASD. This study attempts to determine whether the VPA rat model of ASD exhibits AFS when presented with various diet types. These include standard chow and water, palatable sweet tastants (sucrose, saccharin and complex liquid diet) and finally palatable high fat milks. The mRNA expression levels of oxytocin, oxytocin receptor, dynorphin and kappa-opioid receptor were then determined. These genes have previously demonstrated to be involved in both feeding and social behaviours. The VPA rats were found to consume less standard chow and water, yet increased intake of the sweet tastants was observed. Additionally, in the VPA rats’ oxytocin expression in the hypothalamus was increased, as was dynorphin expression in the hypothalamus and brainstem. Increased expression of the anorexigenic oxytocin may have resulted in the decreased intake of chow and water, and could potentially be a result of increased leptin or melanocortin levels. However, increased dynorphin expression may be responsible for the increased intake of the palatable sweet tastants, via inhibition of proopiomelanocortin or neuropeptide S. The development of effective treatments for AFS in ASD requires an understanding of the underlying neurological mechanisms. This research provides the first evidence of AFS and elevated oxytocin and dynorphin expression in the VPA rat model of ASD, thus paving the way for further research in this area.

text: Characterisation of Food Intake and Expression of Feeding-Related Genes in The VPA Rat Model of Autism Spectrum Disorder Autism spectrum disorder (ASD) is a neurodevelopmental disorder affecting roughly 1% of the global population. Aberrant food selectivity (AFS) is a common comorbid symptom of ASD which can result in nutritional deficiencies, increased parental stress and reduced quality of life. However, alarmingly little research has been conducted investigating the nature and the underlying neurophysiological mechanisms of AFS in ASD. This study attempts to determine whether the VPA rat model of ASD exhibits AFS when presented with various diet types. These include standard chow and water, palatable sweet tastants (sucrose, saccharin and complex liquid diet) and finally palatable high fat milks. The mRNA expression levels of oxytocin, oxytocin receptor, dynorphin and kappa-opioid receptor were then determined. These genes have previously demonstrated to be involved in both feeding and social behaviours. The VPA rats were found to consume less standard chow and water, yet increased intake of the sweet tastants was observed. Additionally, in the VPA rats’ oxytocin expression in the hypothalamus was increased, as was dynorphin expression in the hypothalamus and brainstem. Increased expression of the anorexigenic oxytocin may have resulted in the decreased intake of chow and water, and could potentially be a result of increased leptin or melanocortin levels. However, increased dynorphin expression may be responsible for the increased intake of the palatable sweet tastants, via inhibition of proopiomelanocortin or neuropeptide S. The development of effective treatments for AFS in ASD requires an understanding of the underlying neurological mechanisms. This research provides the first evidence of AFS and elevated oxytocin and dynorphin expression in the VPA rat model of ASD, thus paving the way for further research in this area.

year: 2017

title: Foci-specific Psychological Contracts: Target-similarity effects on foci-specific OCB and Job satisfaction

authors: Khan, Khalid

subjects: Psychological Contracts

abstract: Psychological contracts provide a framework for understanding the employment relationship. The literature on psychological contracts has focused on the relationship of a focal-employee with a 'unitary employer'. This thesis employees the target-similarity model, proposed by Lavelle, Rupp, and Brockner (2007), to extend the psychological contract  framework to include the foci-specific psychological contracts s a focal-person establishes with his/her organisation, supervisor, and peers. Three independent studies were carried out for this thesis. The first two studies concurrently tested the effects of foci-specific psychological contracts breach on work-related outcomes. The first study investigated the effect of foci-specific psychological contracts s breach on OCBs directed at the specific foci. The results from this study indicate that foci-specific psychological contract breach had a target-similarity effect on the OCBs directed at the foci breaching the psychological contracts. Results from this study also indicate that the psychological contract breach by the supervisor has a spill-over effect on the OCBs directed at the organisation and the peers. The results from the second study also confirmed that the foci-specific psychological contract breach had a target-similarity effect on the focal-person's satisfaction with the foci breaching the psychological contracts. Results from this study also confirmed that foci-specific psychological contract breach had spillover effect on the focal-person's satisfaction with the various organisational foci. Study three was designed to empirically test the effects of peer-to-peer psychological contract breach on a focal-person's satisfaction with his/her peers. The results from this study included the identification of the content of the peer-to-peer psychological contract, and confirmed the negative relationship between the breach of peer-to-peer psychological contracts s and satisfaction with peers. Implications for the psychological contract  theory, future research, and practice are discussed at the end of the thesis.

text: Foci-specific Psychological Contracts: Target-similarity effects on foci-specific OCB and Job satisfaction Psychological contracts provide a framework for understanding the employment relationship. The literature on psychological contracts has focused on the relationship of a focal-employee with a 'unitary employer'. This thesis employees the target-similarity model, proposed by Lavelle, Rupp, and Brockner (2007), to extend the psychological contract  framework to include the foci-specific psychological contracts s a focal-person establishes with his/her organisation, supervisor, and peers. Three independent studies were carried out for this thesis. The first two studies concurrently tested the effects of foci-specific psychological contracts breach on work-related outcomes. The first study investigated the effect of foci-specific psychological contracts s breach on OCBs directed at the specific foci. The results from this study indicate that foci-specific psychological contract breach had a target-similarity effect on the OCBs directed at the foci breaching the psychological contracts. Results from this study also indicate that the psychological contract breach by the supervisor has a spill-over effect on the OCBs directed at the organisation and the peers. The results from the second study also confirmed that the foci-specific psychological contract breach had a target-similarity effect on the focal-person's satisfaction with the foci breaching the psychological contracts. Results from this study also confirmed that foci-specific psychological contract breach had spillover effect on the focal-person's satisfaction with the various organisational foci. Study three was designed to empirically test the effects of peer-to-peer psychological contract breach on a focal-person's satisfaction with his/her peers. The results from this study included the identification of the content of the peer-to-peer psychological contract, and confirmed the negative relationship between the breach of peer-to-peer psychological contracts s and satisfaction with peers. Implications for the psychological contract  theory, future research, and practice are discussed at the end of the thesis.

year: 2016

title: In service provision for teachers of Maori language and teachers who teach through the medium of Maori: A working model reviewed

authors: Johnson, Diane

subjects: te reo Māori

abstract: This paper reports on the design, administration and effectiveness of an in-service programme designed by the University of Waikato in partnership with the New Zealand Ministry of Education. The programme aims to: improve language proficiency; assist with the interpretation and implementation of Māori curriculum statements; address issues involved in teaching Māori and teaching through the medium of Māori; assist with lesson planning and lesson delivery, materials development and testing and assessment.

text: In service provision for teachers of Maori language and teachers who teach through the medium of Maori: A working model reviewed This paper reports on the design, administration and effectiveness of an in-service programme designed by the University of Waikato in partnership with the New Zealand Ministry of Education. The programme aims to: improve language proficiency; assist with the interpretation and implementation of Māori curriculum statements; address issues involved in teaching Māori and teaching through the medium of Māori; assist with lesson planning and lesson delivery, materials development and testing and assessment.

year: 2001-02