title: Use of lag schedules to increase play variability across settings for a preschool child with Autism

authors: de Koster, Anna Elizabeth

subjects: Autism

abstract: The importance of play is becoming increasingly evident in the holistic development of young children.  Play develops effortlessly in typically developing children, but in children with autism spectrum disorder (ASD), play needs to be taught explicitly.  Children with autism have limited play variability and often display rigid and repetitive play behaviours, which negatively impact their social functioning and language development.  Play in autism is a really important target behaviour.  Teaching play can improve exposure to learning opportunities, social interactions and increase access to reinforcement, which in turn will improve language acquisition and communication skills.  The primary objective of this study was to determine how lag schedules of reinforcement can increase the play variability of a boy, aged three, with limited play and social skills.  A multiple probe design with a changing criterion design was used across three different play settings: wooden figurine and a doll’s house, water play and a fire station play set.  Results showed that lag schedules were sufficient to increase the play variability for the participant across all three settings.  Generalisation was seen to occur during normal play sessions across various play settings in the early childhood centre, with increases in peer interaction.  The current study provides empirical evidence that supports the use of lag schedule of reinforcement to increase the average play variability in children with ASD.

text: Use of lag schedules to increase play variability across settings for a preschool child with Autism The importance of play is becoming increasingly evident in the holistic development of young children.  Play develops effortlessly in typically developing children, but in children with autism spectrum disorder (ASD), play needs to be taught explicitly.  Children with autism have limited play variability and often display rigid and repetitive play behaviours, which negatively impact their social functioning and language development.  Play in autism is a really important target behaviour.  Teaching play can improve exposure to learning opportunities, social interactions and increase access to reinforcement, which in turn will improve language acquisition and communication skills.  The primary objective of this study was to determine how lag schedules of reinforcement can increase the play variability of a boy, aged three, with limited play and social skills.  A multiple probe design with a changing criterion design was used across three different play settings: wooden figurine and a doll’s house, water play and a fire station play set.  Results showed that lag schedules were sufficient to increase the play variability for the participant across all three settings.  Generalisation was seen to occur during normal play sessions across various play settings in the early childhood centre, with increases in peer interaction.  The current study provides empirical evidence that supports the use of lag schedule of reinforcement to increase the average play variability in children with ASD.

year: 2022

title: Foaming Novatein Thermoplastic Protein

authors: Gavin, Chanelle Anne Rose

abstract: Most plastics are produced from non-renewable and/or non-biodegradable polymers. The negative environmental impact of these has been a strong driver for bioplastic development. Proteins are naturally occurring biopolymers which can be denatured and plasticised to produce thermoplastic materials. Novatein Thermoplastic Protein (NTP) is a patented blend of blood meal (a highly aggregated protein) and processing additives which: reduce hydrogen bonding, break cross links between cysteine residues, disrupt hydrophobic interactions, and facilitate protein unfolding. Water and triethylene glycol (TEG) are added as plasticisers to produce a powder which can be extruded, and subsequently injection moulded.
As Novatein is both bio-derived and biodegradable there is the opportunity for using it as an alternative loose fill packing material. This work aimed to develop an appropriate foaming method and the principles governing it. 
Foaming was initially investigated through extrusion which was unsuccessful due to the low speed and pressure drop. However, by using high speed and pressure, Novatein was successfully foamed in an injection moulder under free expansion. Foaming achieved densities between 0.2-0.5 g/cm3, at temperatures between 160-165°C. The mechanical properties varied with density but compressive strengths between 200 and 600 kPa and elastic moduli between 2.2 and 8 MPa were typical. Increasing temperature further did not improve expansion as the material degraded. The narrow processing window is characteristic of the material’s semi-crystalline nature which arises from residual protein secondary structure (α-helices and β-sheets). Although Novatein softens at high temperature, it does not form a typical melt.
Processing depends upon the interactions between protein, additives, and plasticisers. Highly plasticised Novatein phase separates into protein rich, protein-plasticiser, and plasticiser rich regions. This results in variable morphology characterised by: unfoamed regions, variable cell sizes and both open and closed cells. 

Varying water, urea and TEG impacted the foaming ability; adding urea lowered the extensional viscosity improving foaming while also acting as a blowing agent. Water and TEG reduced the shear viscosity and softening point respectively reducing expansion. Water was expected to improve expansion by acting as a blowing agent, however increasing water and TEG both increased cell size, but delayed stabilisation decreasing expansion.
Following nucleation a bubble grows by diffusion of gas molecules from the surrounding polymer. As these molecules leave, the viscosity increases, controlling bubble growth. Simultaneously, growth causes chain alignment within the surrounding polymer. Through FT-IR, bubbles were shown to appear in regions high in β-sheets. Two mechanisms were proposed; either a bubble nucleates near a β-sheet and grows until it encounters other β-sheet structures or that chain alignment enables hydrogen bonding between the chains, forming these structures. FT-IR also showed a high concentration of TEG at the bubble surface suggesting that nucleation occurred in regions high in water and TEG. The accumulation of TEG at a bubble surface occurs as water (steam) diffuses into the bubble causing expansion, pushing TEG into the surroundings.
Bubble stabilisation is achieved through either a loss plasticiser molecules or a decrease in temperature. In over plasticised blends, water keeps the viscosity in the surrounding polymer low, while increasing TEG reduced the softening point, both allowing more time for gases to diffuse out.
This work developed a suitable foaming method and an understanding of the role of protein secondary structure and rheology for Novatein, which can be foamed despite its high β-sheet content.

text: Foaming Novatein Thermoplastic Protein Most plastics are produced from non-renewable and/or non-biodegradable polymers. The negative environmental impact of these has been a strong driver for bioplastic development. Proteins are naturally occurring biopolymers which can be denatured and plasticised to produce thermoplastic materials. Novatein Thermoplastic Protein (NTP) is a patented blend of blood meal (a highly aggregated protein) and processing additives which: reduce hydrogen bonding, break cross links between cysteine residues, disrupt hydrophobic interactions, and facilitate protein unfolding. Water and triethylene glycol (TEG) are added as plasticisers to produce a powder which can be extruded, and subsequently injection moulded.
As Novatein is both bio-derived and biodegradable there is the opportunity for using it as an alternative loose fill packing material. This work aimed to develop an appropriate foaming method and the principles governing it. 
Foaming was initially investigated through extrusion which was unsuccessful due to the low speed and pressure drop. However, by using high speed and pressure, Novatein was successfully foamed in an injection moulder under free expansion. Foaming achieved densities between 0.2-0.5 g/cm3, at temperatures between 160-165°C. The mechanical properties varied with density but compressive strengths between 200 and 600 kPa and elastic moduli between 2.2 and 8 MPa were typical. Increasing temperature further did not improve expansion as the material degraded. The narrow processing window is characteristic of the material’s semi-crystalline nature which arises from residual protein secondary structure (α-helices and β-sheets). Although Novatein softens at high temperature, it does not form a typical melt.
Processing depends upon the interactions between protein, additives, and plasticisers. Highly plasticised Novatein phase separates into protein rich, protein-plasticiser, and plasticiser rich regions. This results in variable morphology characterised by: unfoamed regions, variable cell sizes and both open and closed cells. 

Varying water, urea and TEG impacted the foaming ability; adding urea lowered the extensional viscosity improving foaming while also acting as a blowing agent. Water and TEG reduced the shear viscosity and softening point respectively reducing expansion. Water was expected to improve expansion by acting as a blowing agent, however increasing water and TEG both increased cell size, but delayed stabilisation decreasing expansion.
Following nucleation a bubble grows by diffusion of gas molecules from the surrounding polymer. As these molecules leave, the viscosity increases, controlling bubble growth. Simultaneously, growth causes chain alignment within the surrounding polymer. Through FT-IR, bubbles were shown to appear in regions high in β-sheets. Two mechanisms were proposed; either a bubble nucleates near a β-sheet and grows until it encounters other β-sheet structures or that chain alignment enables hydrogen bonding between the chains, forming these structures. FT-IR also showed a high concentration of TEG at the bubble surface suggesting that nucleation occurred in regions high in water and TEG. The accumulation of TEG at a bubble surface occurs as water (steam) diffuses into the bubble causing expansion, pushing TEG into the surroundings.
Bubble stabilisation is achieved through either a loss plasticiser molecules or a decrease in temperature. In over plasticised blends, water keeps the viscosity in the surrounding polymer low, while increasing TEG reduced the softening point, both allowing more time for gases to diffuse out.
This work developed a suitable foaming method and an understanding of the role of protein secondary structure and rheology for Novatein, which can be foamed despite its high β-sheet content.

year: 2019

title: The Price of Mauri: Exploring the validity of Welfare Economics when seeking to measure Mātauranga Māori

authors: Awatere, Shaun

subjects: welfare economics

abstract: Since the 1980s New Zealand has pursued neo-classical or market-based policies with a particular fervour. Market-based options are seen by resource management decision makers as essential frameworks for efficiently allocating resources, an approach that continues to support the view of the inherent dominance of Western knowledge. This is particularly concerning, given that Māori (the indigenous people of New Zealand), have an important role to play in New Zealand resource management and perceive their own knowledge systems have been marginalised. The primary goal of this thesis is to explore the validity of welfare economics when seeking to measure quantitatively Mātauranga Māori or Māori views of the environment through the contingent valuation method. A contingent valuation study is carried out using three separate samples drawn from the general Māori population in Auckland city, a hāpu/sub-tribe indigenous to the Auckland isthmus, and drivers of motor vehicles in Auckland city. Data collection modes include a postal survey and face-to-face interviews. This thesis challenges the validity of political-legal ethnicity constructs to measure Mātauranga Māori. The search for a central tendency will lead to biased, misleading and inaccurate results. The thesis also challenges the validity of contingent valuation to produce true economic measures and to measure and identify Mātauranga Māori. Despite advances in analytical techniques, economic efficiency measures are always deficient, given the difficulty of capturing and anticipating all impacts and valuing them appropriately. Mātauranga Māori is derived from a Māori epistemology and should be considered or analysed with primary reference to this body of knowledge. Economic analysis is only one important cog in the machinery of resource management policy. Given that an economist's contribution to local and regional resource management is most valuable when focusing on the  economic efficiency  of the proposed resource allocation, it is appropriate that other perspectives such as Mātauranga Māori be considered.

text: The Price of Mauri: Exploring the validity of Welfare Economics when seeking to measure Mātauranga Māori Since the 1980s New Zealand has pursued neo-classical or market-based policies with a particular fervour. Market-based options are seen by resource management decision makers as essential frameworks for efficiently allocating resources, an approach that continues to support the view of the inherent dominance of Western knowledge. This is particularly concerning, given that Māori (the indigenous people of New Zealand), have an important role to play in New Zealand resource management and perceive their own knowledge systems have been marginalised. The primary goal of this thesis is to explore the validity of welfare economics when seeking to measure quantitatively Mātauranga Māori or Māori views of the environment through the contingent valuation method. A contingent valuation study is carried out using three separate samples drawn from the general Māori population in Auckland city, a hāpu/sub-tribe indigenous to the Auckland isthmus, and drivers of motor vehicles in Auckland city. Data collection modes include a postal survey and face-to-face interviews. This thesis challenges the validity of political-legal ethnicity constructs to measure Mātauranga Māori. The search for a central tendency will lead to biased, misleading and inaccurate results. The thesis also challenges the validity of contingent valuation to produce true economic measures and to measure and identify Mātauranga Māori. Despite advances in analytical techniques, economic efficiency measures are always deficient, given the difficulty of capturing and anticipating all impacts and valuing them appropriately. Mātauranga Māori is derived from a Māori epistemology and should be considered or analysed with primary reference to this body of knowledge. Economic analysis is only one important cog in the machinery of resource management policy. Given that an economist's contribution to local and regional resource management is most valuable when focusing on the  economic efficiency  of the proposed resource allocation, it is appropriate that other perspectives such as Mātauranga Māori be considered.

year: 2008