Masters Theses

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https://hdl.handle.net/10182/10

Theses submitted by Lincoln University masters students.

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Effect of hemp protein hydrolysates on physicochemical properties and digestibility of starch : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science at Lincoln University
(Lincoln University, 2024) Wu, Gaosheng
Starch is the main constituent of the human diet and is included in foods either in the gelatinized or retrograded form. This carbohydrate, produced by plants, contains amylose and amylopectin chains. Depending on the plant source, the proportion of these two glycan chains can vary within the granule, which influences the physicochemical behavior of starch in foods, impacting the textural and nutritional properties of the final food product. Over the past decades, researchers have investigated the impact of the presence and/or complexation of various biomolecules (proteins and polyphenols) with starch on its physical, chemical, and nutritional properties. There is limited research on the development of hemp protein and its hydrolysates in combination with various starch molecules, which could be a promising strategy for enhancing the nutritional and health benefits of foods. Exploring the interaction between hemp protein and different starches could lead to novel functional food ingredients with improved nutritional profiles, offering potential for increased health benefits. Firstly, this study compared the functional and nutritional properties of hemp protein hydrolysates (HPH) prepared with 0.5% Bacillus licheniformis (1 minute) and 2% pepsin protease (60 minutes). Hemp protein hydrolyzed by bacterial protease (HPHB) showed enhanced emulsifying capacity of 47.83 mL/g, compared to 45.83 mL/g for hemp protein hydrolyzed by pepsin (HPHP). On the other hand, HPHP exhibited superior oil absorption capacity of 5.46 g/g, compared to 5.18 g/g for HPHB, as well as higher foaming capacity at 31.2%, relative to 28% for HPHB. The amino acid composition, which affects the overall amino acid profile, was determined using High-Performance Liquid Chromatography (HPLC), a precise technique for separating and quantifying individual amino acids. Secondly, when the effects of HPH on the textural, particle size distribution, structural, and rheological properties of normal corn starch (NCS), waxy corn starch (WCS), and high amylose corn starch (HACS), alongside their impact on antioxidant activity and starch digestibility were examined, this study showed the addition of the HPH to the starch significantly modified the textural properties of starch gels, particularly enhancing elasticity and hardness in WCS and NCS and increasing adhesiveness in NCS and HACS. Notable effects were observed with 20% HPHP on WCS elasticity (0.09 N.s), 10% HPHB on WCS hardness (0.57 N), and 20% HPHB on WCS adhesiveness (-0.15 N) (p<0.05). Particle size distribution indicated substantial granule size increases, especially in HACS (e.g., Dx90 increased from 39.19 μm to 771 μm). FT-IR analysis revealed shifts in absorption peaks, suggesting altered hydrogen bonding interactions without new functional groups. Rheological properties varied, with increased storage (G') and loss (G") moduli in NCS-HPH mixtures and general decreases in WCS-HPH and HACS-HPH. Additionally, a significant reduction in rapidly digestible starch (RDS) was observed with 20% HPHP in HACS, while resistant starch (RS) increased by about 10% with 10% HPHB in WCS (p<0.05). Among the starches, 20% HPHP exhibited the highest antioxidant activity with 232.36 μmol TE/g for HACS, 231.60 μmol TE/g for WCS and 210.42 μmol TE/g for NCS, respectively (p<0.05).
Open Access
Evaluation of food grade products for attractancy to potato tomato psyllid adults infected with or without Candidatus Liberibacter solanacearum : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Agricultural Science at Lincoln University
(Lincoln University, 2024) Braidwood, Kate Alice
Tomato potato psyllid (Bactericera cockerelli (Šulc) (Hemiptera: Triozidae)) (TPP) is an insect, introduced to New Zealand in 2006, which causes significant damage to potato crops on the Canterbury plains of New Zealand. In this study three key aspects of integrated pest management, namely: trapping, biological control and identification of food grade attractants for utilization in a lure, were investigated. In addition, DNA integrity of TPP extracted off yellow sticky cards placed in vivo in potato paddocks was examined. A novel study of 75 food grade products were evaluated for attractancy to TPP adults. Choice testing using a Y-tube olfactometer found that a total of 16 products had attraction at ≥50% for “cold” TPP (i.e. insects with no infection of Candidatus Liberibacter solanacearum (CaLso)). Those attractants included: fatty acids (palm oil + lecithin granules; and macadamia nut oil + lecithin granules); glycerin flakes + lecithin granules; polysaccharides (xanthan gum, micro agar and iota carrageenan, primellose, fermented gelatin type B); disaccharide (trehalose) monosaccharide (xylose); amino acids (glutamine, methionine and valine) an alcohol (96% ethanol) and an acid (phosphoric acid). All of these products were subsequently evaluated for attractancy to “hot” TPP adults (i.e. insects confirmed positive by polymerase chain reaction (PCR) to CaLso). All the amino acids were marginally more attractive to “hot” TPP adults than “cold” ones: methionine (70% vs. 55% respectively), valine (65% vs 60%) and glutamine (55% vs. 50%). Similarly, primellose was also more attractive (60% vs 50% respectively). Xanthan gum, micro agar, trehalose and glycerin flakes + lecithin remained attractive (at 50%), whereas 96% ethanol (45%), iota carrageenan (40%), macadamia nut oil + lecithin granules (40%), phosphoric acid (35%), and palm oil + lecithin granules (25%) were all significantly less attractive than to cold TPP (P<0.01). Two insect traps were compared throughout the 2022/2023 season, the commonly used yellow sticky card and a novel 3-D printed yellow cup-trap, which was also designed to enable housing of an attractant lure. At low population numbers of TPP seen on the Canterbury plains (mostly only 1 or 0 per trap during 2022/23 potato growing season), both trap types were only partially successful in catching TPP. The highest number of TPP caught in late February/early March 2023 was 8 on a sticky card and 3 in a cup-trap. Inclusion of valine, trehalose and palm oil alone or in combination with each other in late summer did not improve efficiency of the cup-traps. To determine DNA integrity of TPP, an in vitro study of insects harvested from colonies raised in an acrylic sheet-covered greenhouse found that DNA of a single insect, captured off potato plant into a plastic vial, regardless of age, could be successfully amplified using PCR. In vivo studies found that at least 3 young, light-coloured, TPP adults must be combined in a pooled sample to successfully amplify their DNA. Pooled samples of 5 young TPP adults were placed on yellow sticky cards in vivo in a paddock in autumn. DNA of each pooled sample was then analysed using PCR on days 1 to 7, 10 and 14 in the field. DNA integrity was maintained up to 6 days under field conditions. This research successfully identified 13 potential products which show potential for use as an attractant lure, although performance in the field against low density populations was not strong. Field use of cone-shaped traps was the first in New Zealand, allowing the inclusion of a lure. In addition, TPP DNA extracted off yellow sticky cards over 1-14 days in the field, found reducing ability to detect TPP over time using PCR, leading to the recommendation that extraction was best done within 7 days, ideally 5 or more TPP as a pooled sample should be used for PCR extractions.
Open Access
How can landscape architecture create living environments that promote access to public transport, housing, and green spaces : A dissertation submitted in partial fulfilment of the requirements for the Degree of Master of Landscape Architecture at Lincoln University
(Lincoln University, 2024) Koch, Dominic
This study seeks to understand how to address thematic social justice issues through spatial design using landscape architecture. More specifically, whether, how and to what extent different city municipalities address resident accessibility issues relating to Social (or Affordable housing), Green Space and Public Transport through design? To understand how these thematic issues are addressed through design, city design guidelines will be critically analysed specific to these themes. The city design guidelines of Wellington, Christchurch and Amsterdam will be used for this study. Findings will inform models of proposed land use types and extent in Tauranga City to create equitable outcomes for all its residents.
Open Access
Estimating diet of the European hedgehog (Erinaceus europaeus) using molecular analysis of faeces and colon content : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science at Lincoln University
(Lincoln University, 2024) Walker, Maryanne
New Zealand has a unique ecosystem that evolved without the presence of mammalian predators. Since human colonisation, several species of mammalian predators have been introduced, including the European hedgehog (Erinaceus europaeus). The hedgehog, in its native range, mainly feeds on invertebrates, with minor dietary components of bird eggs and lizards. I used molecular methods to analyse the diet of hedgehog in New Zealand. Molecular methods have an important advantage over the traditional visual analysis of faeces and stomach contents as they allow for better identification of soft-bodied remnants of prey items. I successfully used species-specific primers to detect a known species (mealworms, Tenebrio molitor) in hedgehog faeces after a controlled feeding trial. Next, I trialled a simple visualisation method to compare the quality of DNA extracted from hedgehog stomach and colon contents. Unfortunately, the visualisation method trialled did not determine any differences in the DNA quality of the two sample sources and further trials are required. I created a local reference database of invertebrates collected from pitfall trapping at Kaitorete Spit. Barcode sequences developed for the local reference library were uploaded to BOLD systems to contribute to the growing global database of sequences. This local reference database successfully enhanced the taxonomic rank assignment of amplicon sequence variations produced during metabarcoding. I used high throughput sequencing on faecal and colon samples. Several taxa from the phyla Arthropoda, Annelida, Mollusca, Nematoda, and Rotifera were identified and reported at the genus and family (for Arthropoda) taxonomic level. There was a considerable level of taxon heterogeneity in the prey items not between samples. High abundances of Arthropoda were identified in colon samples, while faecal samples had higher abundances of all other phyla. The results from this study are consistent with earlier morphological studies of hedgehog diets in New Zealand and Europe but add greater detail. The dietary results from this study are important and applicable in both New Zealand and worldwide. For New Zealand, this study contributes to understanding the ecological impacts that hedgehogs have in New Zealand while providing justification for ongoing monitoring plans that control hedgehogs to prevent detrimental impacts. Worldwide, these methods can be used, especially in the hedgehog’s natural habitat, to understand their natural diet to assist with conservation where this species is endangered. Future studies should expand the area studied to explore dietary variation across a spatial scale and where other endangered species are at risk from hedgehog predation.
Restricted
Bait preferences in rabbits (Oryctolagus cuniculus) and non-target species in rabbit-prone areas of New Zealand’s South Island : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science at Lincoln University
(Lincoln University, 2024) Meban, Anna
Rabbits (Oryctolagus cuniculus) are an introduced pest species that plagues New Zealand’s dryland and semi-arid environments. They are particularly abundant in areas of the South Island, including the Mackenzie Basin and Central Otago region. The current best practice for rabbit control is aerial distribution of carrot and cereal baits laced with pindone or 1080. Carrot tends to be the most preferred bait type; however, it poses issues in terms of its quick deterioration in field settings, as well as being costly and time-consuming to produce. With pest control in New Zealand focusing on eliminating predator-free species, there are large gaps in knowledge surrounding the development of more effective rabbit control tools, as well as the monitoring of non-target species present in rabbit settings. I conducted bait palatability trials, testing several novel and current baits to determine preferences in both rabbits and non-target species. An initial trial was run at Mt. Grand Station (Lake Hawea) in August 2023, testing four different bait types (fresh carrot, carrot jam, carrot oil mayonnaise (mayo) and RS5 non-toxic cereal pellets). Bait types were rotated through covered and uncovered bait stations. A further trial was run at Lilybank Station (Lake Tekapo) in October 2023, testing four bait types (fresh carrot, carrot jam, and two new cereal pellets A & B (formulated by Kiwicare), without using the covered bait stations. Interactions with all bait types were low. The bait types most interacted with by rabbits were fresh carrot and carrot jam. Visits were much more abundant than interactions. Rabbits visited carrot the most at Mt. Grand and cereal pellets B at Lilybank. Despite little consumption of bait types, they were still successful at luring individual rabbits to a site. Many non-target species were present in these rabbit environments. At Mt. Grand, blackbirds were the species that had the most interactions overall, mostly with carrot jam. At Lilybank, possums were the non-target that showed the most interactions, with the preferred bait type also being carrot jam. There was some neophobia toward covered bait stations, with visits at Mt. Grand decreasing as time went on, and interaction levels staying consistently low until the bait was placed outside the covered bait stations. At Lilybank (where covered bait stations were not used), there was a small increase in both visits and interactions over time. Activity data suggested that rabbits are most active around the sunset period and during the night. Further testing of novel bait without covered bait stations is required to better understand bait preferences without the effects of neophobia. The results produced by this study suggest that carrot jam or a bait type with high carrot content, should be successful at initiating pest rabbit interactions. However, further development and refinement is required to mitigate the risk associated with non-target species.
Open Access
Our electric futures: understanding the role of hydrogen in providing dispatchable demand to the New Zealand grid : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
(Lincoln University, 2024) Harrison, Amy
As the electricity sector globally turns toward renewables, renewable sources of dispatchable electricity generation and demand (also known as interruptible load) become increasingly important. Without dispatchable generation and/or demand, balancing of electricity supply and demand across a range of time scales cannot take place, undermining grid reliability, particularly with ever increasing demand for electricity through both population growth and electrification for decarbonisation. Hydrogen production by electrolysis from renewable energy has been proposed as a renewable source of dispatchable energy across all time scales. This thesis considers the use of large-scale hydrogen production for grid balancing in New Zealand as a case study. The proposed departure of Rio Tinto from New Zealand (and subsequent closure of the Tiwai aluminium smelter) would make available the smelter demand capacity (630 MW) to the grid. This thesis takes a what-if approach to determining the value of replacing the smelter with variable hydrogen production for grid balancing and downstream decarbonization. The historical electricity demand profile of the Tiwai smelter between 2010 and 2019 (which represents near complete utilisation of Manapouri output) is modelled to produce hydrogen under a range of optimisation scenarios (volume (base case), cost, renewability, load shifting). In each case, the hydrogen production volumes, cost of hydrogen production and grid renewability was evaluated. Optimising for volume, cost and load shifting provided 150-260 t/d of hydrogen production, enough to meet several potential sources of hydrogen demand in New Zealand, including transport, industrial process heat, and chemical production. However, the cost and load shifting scenarios experienced significant production volatility, limiting their usefulness for industrial demand. Optimising for electricity renewability produced negligible amounts of hydrogen (5.7 t/d). The cost of hydrogen produced under two scenarios (volume – 8.23 NZD/kg; cost – 7.97 NZD/kg) is on par with previous reports of hydrogen use for grid balancing in New Zealand. Load shifting is slightly more expensive (11.16 NZD/kg) while the renewability scenario was found to be prohibitive cost wise (90 NZD/kg). None of the scenarios could achieve 100% renewable energy at any point across a daily (hourly average) or annual profile (daily average). The renewability and load shifting scenarios achieved an average of 90 and 82% renewables. Cost and volumes scenarios did not significantly change the average renewability share from the historic average of 78% over the period studied. Given the trade-offs between these scenarios, the load shifting scenario appears to be optimal for the grid, providing improved renewability and critical dispatchable energy at a moderately competitive price.
Open Access
Investigate feasibility of utilising a neural-networked set of inertial measurement units to compensate for variations in motion of a commercial radio-controlled vehicle in a dryland agricultural context : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
(Lincoln University, 2023) Davidson, Brett
Image stabilisation is desired for efficient identification of objects in the path of a self-driving vehicle. The gyroscope and accelerometer of an inertial measurement unit (IMU) can be used to derive the movement of a vehicle, which can then be used by a rotation matrix to compensate for this movement, but a gyroscope has inherent “drift” errors, and while the accelerometer of an IMU is more accurate, it has a slower response time, which reduces the detection rate. Various methods have been proposed to compensate for these sensor limitations. Kalman filters are often used in industry to fuse gyroscope and accelerometer data to reduce the effects of drift, noise, and other gaussian-based errors but these are computationally intensive for the sort of lightweight processor that a radio-controlled car could be expected to power. A complementary filter such as Madgwick’s is a simpler and less processor-intensive solution with claims that the method is just as accurate. Both of these approaches are applied on a single IMU. Averaging multiple IMUs has been investigated and offers slight improvements. Well-trained neural networks also offer IMU compensation but are computationally and time expensive to train to generate a model however the application of previously-trained models is less intensive and is becoming common as processor power improves. There have been no investigations of using a neural network on multiple IMUs as of this time. This project investigates if using a neural network of multiple IMUs reduces errors and enhances performance compared to a single IMU. The Kalman filter is used as baseline control data and three neural network models (MLP, NARXNET and RBF) are compared against each other and a Madgwick complementary filter to investigate if using a neural network of multiple IMUs reduces errors and enhances performance compared to a single IMU in the context of establishing Euler angles of roll and pitch movement to stabilise a video feed of a consumer-level camera on a moving commercial off-the-shelf radio control vehicle. It is demonstrated that there is no statistically significant advantage in using multiple IMUs if these are kept in the same horizontal plane, that a minimum of a three-layer MATLAB NARXNET filter provides the equivalent accuracy of a Kalman filter with similar processing times, and that the Madgwick IECF6 complimentary filter, the radial basis factor neural network and multi-level perceptron neural network models are not fit for this purpose.
Open Access
The wellbeing experience within a New Zealand township. New Zealand Treasury’s Living Standards Framework in a hyper-local context : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
(Lincoln University, 2023) Troy, Helen
The New Zealand Treasury published ‘Te Tai Waiora’, its first wellbeing report in November 2022. The report presents data on how wellbeing has changed, how wellbeing is distributed and the sustainability of wellbeing in Aotearoa New Zealand. The data collected are analysed using the Living Standards Framework, which provides New Zealand Treasury with a systematic approach to offer policy advice and identify the implications of policy, based on a range of evidence gathered over time. This research tests the Treasury’s Living Standards Framework at a hyper-local scale (focusing on matters within a small community or specific geographic location), to understand the extent to which a central government approach to measuring wellbeing is appropriate at a local scale. This study found that indicators that provide data for analysis require context and are most relevant when applied ‘at scale’ to identify the wellbeing experience of individuals and communities. Using a mixed methods approach, the data from the quantitative research showed individuals are significantly more satisfied with various aspects of wellbeing at a local scale than at a national scale. These aspects include the natural environment, safety, housing affordability and political voice. In the qualitative data, it was found that, through a series of processes an individual generates their own wellbeing depending upon capabilities, financial security, locality and employment mobility opportunities. Individuals improved their wellbeing by making deliberate choices within the context of those capabilities. Home ownership was associated with employment mobility and individuals made trade-offs between dimensions of wellbeing as a function of personal value. Both research methods revealed that ‘local matters.’ The findings from this study will contribute to the growing literature on wellbeing. This thesis demonstrates that measuring the wellbeing experience of a small community in a specific geographic location can result in significant differences in wellbeing experiences between the national and local scale. Therefore, adopting an ‘at scale’ approach is more appropriate for policy development if central government is concerned with the wellbeing of all New Zealanders, irrespective of their locality.
Embargo
Evaluating the in vitro efficacy of Abamectin and Fluopyram, alongside hot water treatments against Meloidogyne incognita and Globodera rostochiensis : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
(Lincoln University, 2023) McDonald, Marissa
Plant germplasm importation into Aotearoa/New Zealand poses a risk of introducing unwanted organisms. Current biosecurity measures for plant nematodes on imported nursery stock are under review. This study aimed to investigate alternative chemicals that could replace fenamiphos, the current border treatment. Abamectin and fluopyram were chosen for assays based on their demonstrated nematocidal activity and availablity. Hot water submersion was also tested as a non- chemical alternative. Pratylenchus sp. were extracted from field samples and identified using morphology and molecular methods. Cultures of Meloidogyne incognita and extraction of Globodera rostochiensis cysts were successful, but Pratylenchus sp. cultures could not be established. Preliminary experiments tested the field rates of abamectin (0.009 g/L a.i) and fluopyram (0.3 g/L a.i.) individually and in combination, along with two fenamiphos concentrations (2 g/L and 40 g/L). Abamectin and fluopyram resulted in paralysis rates of ≥ 66.7% in M. incognita J2s, while fenamiphos exhibited no significant differences from the negative control. All treatments produced reversible effects on J2 immobility, indicating a nematistatic effect. Hot water experiments at 44°C for 3 hours caused complete and irreversible paralysis in M. incognita J2s. Further experiments using varying concentrations of abamectin and fluopyram on M. incognita J2s, indicating the highest paralysis rate with abamectin (0.09 g/L a.i.) was 75.2%, while concentrations of fluopyram ≥ 0.6 g/L resulted in 100% paralysis. All combined concentrations of abamectin and fluopyram resulted in 100% paralysis, as did hot water treatments for 1 and 2 hours at 44 and 50°C. In preliminary experiments, no chemical treatments achieved complete mortality in G. rostochiensis juveniles, and no significant differences were observed in the proportion of immobile juveniles compared to the negative control. Hot water treatments at 44°C for 3 hours, in combination with abamectin, fluopyram, abamectin and fluopyram together, and 40 g/L fenamiphos, completely immobilized G. rostochiensis juveniles 48 hours after treatment. Retrospective analysis found the G. rostochiensis experiment results inconclusive due to assessing viability based on movement rather than more precise methods. A preliminary trial using Meldola blue stain revealed that live G. rostochiensis juveniles remained unstained, while dead juveniles stained when exposed to 0.05% Meldola blue for 3, 5, and 7 days. This method was incorporated into further G. rostochiensis experiments. Further chemical experiments on cysts showed no differences compared to the negative control of RO water based on the proportions of juveniles stained with Meldola blue. Hot water treatments at 44°C and 50°C for 1 and 2 hours caused a lower percentage of deceased juveniles compared with the negative control of 24°C. Further experimentation using in planta bioassays are recommended to assess how the chemicals affects nematodes contained within plant tissues as well as plant viability. Expanding the research to encompass a broader range of nematode species is also recommended. Overall, the study demonstrated the potential of abamectin, fluopyram and hot water submersion which provided the complete mortality required in biosecurity situations as alternatives to fenamiphos for biosecurity measures in Aotearoa/New Zealand.
Embargo
New Zealand wine exports to China: Barriers and potential mitigation strategies : A thesis submitted in partial fulfilment of the requirements of the Degree of Master of Commerce and Management at Lincoln University
(Lincoln University, 2024) Yu, Hao
With the gradual expansion of Asian wine consumption in the past decade, China has become Asia’s largest and most significant wine consumption market. As a result, China has become one of the most significant target markets for New Zealand wine exports to Asia. In terms of purchasing power, China is a large potential market. However, Chinese wine consumption has declined recently, and New Zealand's wine market share in China has stagnated. Because of a different drinking culture, government policies, and COVID-19, exports of New Zealand wine to China have encountered various barriers, especially during the pandemic, that eventually prevented New Zealand wine exporters from exploring the Chinese market. This study reviews the global wine industry, the New Zealand wine industry, and the Chinese wine market recently. The literature review focuses on Chinese wine consumers’ preferences, export strategies, and a framework for export barriers. The study uses in-depth interviews with New Zealand wine exporters and Chinese wine importers to investigate New Zealand wine exporters’ backgrounds, export processes, entering the Chinese market mode, export strategies, and various barriers encountered in exporting to China. According to the findings, potential strategies are proposed to mitigate the barriers encountered by New Zealand wine exporters. The primary data were obtained from semi-structured interviews of 12 wine exporters in New Zealand between June and August 2023. These exporters are also local wine producers and export their products. The interviewees are leaders directly engaged in wine exporting or understand the relevant export business currently working as New Zealand wine exporters. Secondary data come from literature studies and published reports by research institutions. Three Chinese wine importers in Shanghai were also interviewed to understand the barriers to New Zealand exporters from a different perspective. The results show that indirect exports are more suitable for entering the Chinese market. Successful exporting is related to rich exporting experience and adequate financial and human resources. The recent barriers New Zealand wine exporters face include exogenous, procedural, resource, and knowledge and experience barriers. Exporters can actively enhance export knowledge and accumulate experience to mitigate the impact of export barriers on enterprises. The results provide new evidence of the success of New Zealand wine exporters in exploring the Chinese market. The results also give policymakers insights on exporting to China, increasing their export experience, and mitigating and eliminating the main export barriers to speed up internationalisation.
Embargo
Identification and characterisation of Saccharomyces cerevisiae strains isolated from spontaneous fermentation of organic Pinot noir wines : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Science at Lincoln University
(Lincoln University, 2024) McKendrey, Jayanta Whitley
This study characterised Saccharomyces cerevisiae populations from the spontaneous fermentation of organic Pinot noir wines produce in Waipara, Aotearoa New Zealand, using a DNA-based Interdelta typing method to evaluate their strain diversity and population dynamics. One hundred and sixty-one S. cerevisiae isolates from key fermentation stages were differentiated by interdelta typing into 106 different genotypes (profiles), of which 24 were observed more than once. One interdelta genotype was observed among each of the fermentation stages studied. The S. cerevisiae population showed a high level of strain diversity with evident dominant groupings of strains during and between fermentation stages. Saccharomyces cerevisiae strain diversity increased towards the end of fermentation accompanied with late-stage dominance by the species. Spontaneous fermentation of organically produced wine may harbour a genetically diverse population of S. cerevisiae strains but appears to be dominated by few genotypes. The influence of each genotype on the organoleptic properties of the eventual product is unknown at this point. However, the use of interdelta typing to identify strains of special relevance with commercial potential is supported.
Open Access
Newly-claimed seascapes: Options and potential applications : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science in Environmental Management at Lincoln University
(Lincoln University, 2023) White, Faye Rose
Worldwide, communities and natural ecosystems are challenged by rising seas. Understandably, much of the response has focused on hazard mitigation to protect human populations, investment and infrastructure. As communities are forced to retreat from coastal areas and as inundation occurs, our coastal margins will change. I term these newly inundated areas “newly-claimed seascapes” (NCSs). The available options for NCSs are currently unclear. For some places, where the social, political and environmental conditions permit, there may be opportunities to repurpose them. For example, for sheltered coastal areas, shallow estuaries and harbours, they could be repurposed for aquaculture, fisheries, wetlands, and/or blue carbon. To aid policy and community preparation, this research used a global systematic literature review to identify options for NSCs. Thirty-nine potential options were identified and categorised to aid policy reform and coastal adaptation. Using Aotearoa/New Zealand as a case study to explore whether repurposing is feasible under current legislative frameworks, I undertook a content analysis of applicable legislation and policy. Finally, to determine the current state of play for local planning in this context, I interviewed a representative of regional councils currently reviewing their regional coastal plans to ascertain whether they are considering repurposing NCSs. Whilst repurposing is implicitly enabled under the current legislation, it is not explicitly directed. As a result, the interviewed regional councils were not preparing to repurpose NCSs at the time of this research. Given that the time to find solutions for coastal areas is becoming increasingly constrained, I argue that the PARA (protect, accommodate, retreat, avoid) management framework currently being promoted as best practice in responding to sea-level rise could be extended to PARAR to include the term Repurpose. Repurposing could help to broaden perspectives on sea-level rise from a sense of fear and loss to positive solutions and opportunities.
Open Access
Artificial neural network approaches for modelling complex biological network – Mammalian cell cycle : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
(Lincoln University, 2023) Sorthiya, Komal
An important process in the growth of any biological organism is its ability to proliferate, a tightly controlled process in which a cell divides into two genetically identical daughter cells. This happens within a dynamic environment, where a cell responds to various internal and external signals through a well-ordered sequence of events called the cell cycle. Underlying these events is a complex and elegantly orchestrated web of interactions that function as an integrated system with various sub-systems that specialise in various tasks. Two such important tasks include cell cycle initiation in response to proliferative signals and the interaction of numerous elements for the completion of the cell cycle. This results in a highly complex system. Any malfunctioning during cell cycle division can cause diseases like Cancer. For gaining insights into biological reactions and their effects, cellular modelling approaches have contributed immensely. A few gaps are recognised in the field after reviewing the literature on mammalian cell cycle modelling. Most models are based on mathematical formulation representing the dynamic behaviour of the cell cycle which includes varied equations ranging from a few to tens of equations. They produce accurate systems dynamics, but the models are complex to solve and require the knowledge of many parameters. On the other hand, Discrete Models are simpler and use a qualitative approach but have numerous limitations to represent the continuous dynamics of the Mammalian Cell cycle. Therefore, there is a need for a modelling approach that is simplified but comprehensively represents the system. Mainly, the representation of a complex system in a robust way is a crucial demand. Our research mainly aims to introduce Artificial Neural Network approaches that mimic the mammalian cell cycle in an intuitive way. The goal is to explore the updated biological knowledge and develop ANN-based mathematical models to check their capabilities for mimicking cell signalling mechanisms.
Embargo
The role of information in land-use decision-making : The perspective of farmers in New Zealand :
(Lincoln University, 2023) Blake, Aimee
Agri-food systems are facing increasing pressure to transition toward more sustainable alternatives, which are information-intensive and may require different forms of knowledge. Therefore, optimal and sustainable land-use decision-making requires effective information provision. However, digital technologies and the information age have changed the ways in which farmers interact with information. This necessitates different approaches and raises questions regarding how and why farmers gather information and whom they trust. Thus, the purpose of this study was to explore the role of information in land-use decision-making from the perspective of farmers in New Zealand. Twenty-two semi-structured interviews with commercial pastoral farmers and a focus group with emerging young farmers were conducted. The results evidence that information is important for decision-making and that gathering processes are personal and contextual. The farmer participants sourced information from a variety of sources across digital and physical formats. Traditional institutions (i.e., industry groups) were recognised; however, digital and informal sources (i.e., the internet and interpersonal networks) were the most utilised. The farmer participants engaged as researchers and information curators online and within networks, to share learnings in communities of practice. The young farmer participants particularly interacted digitally, following farmer influencers and utilising artificial intelligence (AI). Audio formats were acknowledged as useful, and information about consumers was important, signalling market orientation. Combining formal and informal elements, the farmer participants valued how catchment groups are community-led and outcomes-focused. Additionally, knowledge brokering through intermediaries at the catchment level assisted with information exchanges. The most trusted sources of information were other high-achieving farmers and interpersonal networks; however, there were mixed experiences with peers. Validation of information occurred through a triangulation and cross-referencing process. Attempts to determine what is trustworthy were challenging due to misinformation and information overload, which hindered effective decision-making. Farmers largely felt that strategic land-use information was challenging to source, especially in relation to regional contexts. Overall, the results signal the need to combine the best of informal and formal sources and that farmers should be recognised as co-creators of information. This research contributes to the literature on information and farmer decision-making in the information age. Potential actions that emerge from the findings include improving digital literacy, hybrid approaches to information provision, adopting listening rather than telling approaches, and supporting intermediaries. These insights could be of interest to inform effective approaches to information provision. Future research into digital literacy, the perspectives of information providers, and the influence of evolving sources (i.e., AI) would be useful. Additionally, the implications of misinformation and information disorders on trust and decision-making should be considered. It is concluded that as technologies evolve, an ongoing conceptualisation of information and farmer habits will be required.
Open Access
How can the design of wineries support wellbeing? A study of wineries in Waipara, Aotearoa New Zealand : A thesis submitted in fulfilment of the requirements for the Degree of Master of Landscape Architecture at Lincoln University
(Lincoln University, 2023) Goh, Jiang Han Jeremy
Wine and food share important connections to the landscape, and these connections are increasingly being recognised as important to wellbeing. Farmers’ markets and locally focused food menus, alongside the heightened awareness of the value of being in landscape settings, exemplify the significance of opportunities to enjoy the fruits of the earth within the landscape that produced them. However, while there is an established understanding of the connections between nature and wellbeing, and a growing number of studies of gastronomical aspects of the food-landscape relationship, there is little research on how wineries might also offer wellbeing benefits. Locating and identifying patterns of how wineries are designed can offer insight into the place-specific experiences that are encouraged within wineries, the activities provided and how future wineries may be designed to support wellbeing. The goal of this research is to determine how wineries as places - including their location, design, and activities - support wellbeing. A two-phase process was used to identify potential winery cases across Aotearoa New Zealand, followed by a detailed selection based on their landscape, spatial settings, and location. Then from the samples identified, wineries with similar activities were selected and compared based on their landscape and spatial settings. Using a Mash-Up approach, categories and qualities were extracted from parallel studies of institutions known to support wellbeing such as hospitals, schools, and universities. The categories of Vegetation and Nature; Social; Environmental Control; Inclusivity; Spatial; and Multi-Sensory were identified from the parallel studies. Two additional categories were identified at the case study sites, they are: Animals and Time. Field work involved on-site inventorying at the four sites, using the categories derived from the parallel studies. Lastly, a normative critique of the case study sites was conducted that identified a wide range of landscape elements that echo those from the parallel studies, and indicate that wineries - like schools, hospitals, and universities - have a role to play in supporting wellbeing. This research identifies valuable insights into how wineries offer restorative environments and this in turn can inform other settings, such as those from the parallel studies.
Open Access
Impact of mobile payment adoption on household expenditures and subjective well-being : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Commerce and Management at Lincoln University
(Lincoln University, 2023) He, Quan
In recent years, mobile payment has gradually become increasingly popular worldwide. Especially in China, mobile payments are ubiquitous and gradually replacing traditional cash payments. This thesis estimates the effects of mobile payment adoption on household expenditures and subjective well-being. It considersfour categories of household expenditures (clothes, durable goods, consumer goods, and cultural and leisure activities) and four indicators (life satisfaction, contentment, income satisfaction, and depression) of subjective well-being. This thesis uses the Augmented Inverse Probability Weighting estimator to analyse the 2017 Chinese General Social Survey data while accounting for the selection bias inherent in mobile payment adoption. The empirical results show that people’s decisions to adopt mobile payments are positively associated with their educational level, car ownership, social interaction, Internet penetration rate, and residential location. Mobile payment adoption significantly increases household expenditures on consumer goods and cultural and leisure activities but not on clothes and durable goods. Moreover, mobile payment adoption significantly decreases contentment while increasing depression. This thesis also finds that mobile payment adoption significantly decreases urban people’s contentment but significantly increases urban people’s depression. Disaggregated analyses show that mobile payment adoption increases spending on consumer goods but decreases contentment for urban households; increases spending on consumer goods and depression for rural households; increases spending on consumer goods; decreases contentment and income satisfaction for male respondents; and increases spending on clothing, cultural, and leisure activities, and depression for female respondents. Therefore, the government should create products and services to extend the benefits of mobile payments to all segments of Chinese society. At the same time, it should help consumers avoid the debt incurredthrough educational programs and advertising.
Open Access
Clean energy use and subjective and objective health outcomes in rural China : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Commerce and Management at Lincoln University
(Lincoln University, 2023) Zhu, Huanyu
One of the United Nations' Sustainable Development Goals is to ensure access to affordable, reliable, and sustainable energy for all. This thesis analyses the impact of clean energy use on rural residents' subjective health outcomes (self-reported health status, health change, and discomfort) and objective health outcomes (the incidence of bronchitis, asthma, and medical expenditure and fitness expenditure). Using an Inverse Probability Weighted Regression Adjustment (IPWRA) estimator and the 2018 China Family Panel Studies data, this thesis addresses the selection bias associated with clean energy use and estimates unbiased treatment effects. The empirical results show that farmers using clean energy (liquid gas, natural gas, methane, solar energy, or electricity) as the primary cooking fuel report improved health, a lower probability of physical discomfort, and higher fitness expenditures than non-users. Clean energy use does not significantly affect self-reported health, the likelihood of having bronchitis and asthma, or medical spending. The estimates of the propensity score matching model verify the robustness of the results estimated by the IPWRA estimator. The disaggregated analyses reveal that male clean energy users were more likely to report improved health conditions, whereas female clean energy users were less likely to report discomfort during the reference year. Besides, households in income tertile 1 were more likely to report improved health, whereas their counterparts in income tertile 2 were less likely to feel uncomfortable. Households in income Tertile 3 were associated with a high level of fitness expenditure. The results of the theses also show that farmers’ decisions to use clean energy are positively associated with their educational level, household income, whether they rent farmland, and their happiness levels but are negatively related to their age, family size, whether they own real estate, and the ratio of elders in their household. The findings of this thesis emphasise the importance of promoting rural energy transition to improve social health outcomes.
Embargo
The relationship between team structure and technological advancement in Formula One : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Commerce and Management at Lincoln University
(Lincoln University, 2023) Thomas, Anisha Andrew
Formula One is renowned for its global reach, technological advancements, and the skill required to compete at the highest level. While the sport has historically been associated with innovation and the evolution of technology, there is a growing concern that Formula One has become more conservative and risk-averse in recent years, with regulations limiting true innovation. Additionally, financial pressures have shifted the focus towards incremental evolution rather than groundbreaking innovations, leading to a lack of diversity in engine manufacturers and a concentration of power among a few dominant teams. This thesis aims to investigate the role of team structure in determining the level of technological innovation or evolution pursued by Formula One teams. It explores the hypothesis that Entrepreneurial teams are more likely to drive Innovation, while corporate teams tend to focus on evolutionary changes within the sport. By analysing secondary data and conducting statistical analysis, the study examines the historical progression of Formula One, ownership structures within the sport, and the evaluation of technological development encompassing both innovation and evolution. The analysis of the data reveals that radical innovations in Formula One were predominantly driven by Entrepreneurial teams in the early years of the sport. However, as corporate participation increased, revolutionary innovation diminished over time. This contradicts the conventional theory that suggests larger firms with greater capital investments are more successful. Corporate interests, risk aversion, cost control, and profitability concerns have led to stringent rules and regulations that restrict teams' ability to innovate. To reclaim its status as the pinnacle of motorsports, Formula One must shift its focus towards nurturing and supporting entrepreneurial organisations that drive innovation. By fostering an environment that empowers these entities, the sport can rejuvenate its reputation as a breeding ground for groundbreaking technological advancements. While this study provides valuable insights into the relationship between team structure and technological development in Formula One, further research using primary data collection methods and updated information is needed to explore additional linkages and relationships.
Open Access
New Zealand attitudes towards the emerging sport of Esports: Content analysis of New Zealand public discourse on Esports : A thesis submitted in partial fulfilment of the requirements for the Degree of Master of Applied Science at Lincoln University
(Lincoln University, 2023) Benden, Jenn.
Globally, esports is no longer a new activity due to the expansion of esports tournaments, university scholarships, large sponsorships, and well-documented growth in popularity. Despite the global growth, esports and esports research in New Zealand is in a preliminary phase, with a national sporting body for esports only being approved in 2016. This research sought to develop an understanding of the prominent conversations, attitudes, and discourse in New Zealand through analysing publicly available articles and documents written in New Zealand and by New Zealand authors. A qualitative content analysis method (Bengtsson, 2016) was chosen, focusing on a sentence-by-sentence coding methodology. It was found that esports is yet to be accepted in public discourse, with articles repeatedly using justification language to defend esports against stereotypes and criticisms. Sport was conversely not criticised for these same objections, despite many of the criticisms being challenges sport also faces. Sport continues to be upheld in public discourse in New Zealand as an inherent ‘good’ regardless of potential negative outcomes for participants, while esports is not provided the same benefit of social acceptance, confirming again the Great Sport Myth (Coakley, 2015). Beyond comparisons to sport, it was found that esports faces similar criticisms to videogames, adding to the difficulty of esports finding full acceptance socially and politically. While the data gathering method was set to rule out irrelevant articles, it was not possible to fully separate videogame content from esports content. Future research could compare the videogame and esports discourses to determine whether the themes are the same, similar, or different. Other future research opportunities found include determining a clear picture of the demographics of New Zealand esports players and fans, as well as investigating the current and potential future locations of esports facilities in New Zealand.
Open Access
Modification of soil biogeochemistry by plants during a restoration trajectory (Punakaiki, New Zealand) : A thesis submitted in partial fulfilment of the requirements for the Master of International Nature Conservation at Lincoln University
(Lincoln University, 2023) Wang, Yuxuan
The Punakaiki Coastal Restoration Project (PCRP) was carried out to restore native vegetation in a farmed pasture, aiming to establish a functioning sandplain. More than 30 species and >150,000 individual plants were transplanted from containers-grown specimens across the 70 ha site on a pragmatic and adhoc basis over several years. A restoration trajectory is also an ecological succession with temporal changes in species composition of plant communities. The present study focuses soil biogeochemistry in areas of the site where different plant species have been planted. Plants and soils were sampled from different locations at PCRP, and chemical properties of these samples were analysed using ICP-OES to determine macronutrient and trace elements. Olsen-P, mineral nitrogen, soil pH, and organic matter were also analysed. Olsen- P was determined using colorimetrically, while mineral nitrogen was determined using a triple-channel CHN analyser. The results showed that soil chemistry varied beneath different plant species, indicating that plants have different potentials to influence soil nutrient concentrations. Nutrient concentrations also varied with soil depth. Soil concentrations of NO3-N, Fe, Mn, Mo, Na, P, and S differed significantly under different species. Patterns of similarity and differences within the data were investigated. The study also found that a major factor causing the element difference under different plants was site variation. Soil samples were taken from the transects with different soil ages. Younger soil was more likely to contain more abundant trace and major elements and more biological activity, and soil pH was also impacted by soil age. Nutrient concentrations in soil and foliage were often either positively or negatively correlated. Whist primary minerals usually determine major nutrients and trace elements in the soil, differences can be due to passive or active absorptive channels in the soil and by physiological differences between plants. Rhizosphere processes can also alter soil chemistry. Coprosma robusta showed a passive response to salinity, suggesting it might be unable to regulate Na uptake, with a positive correlation between soil Na and foliage Na. By contrast, Coprosma propinqua appeared to actively control uptake of Al, Mg, Na, and Ni; it was the only species that showed a potential mechanism for exclusion of some elements, with a negative correlation of these elements between foliage and soil. The effect of rhizosphere processes on soil organic matter depends on plant species and soil properties, and microorganism activity and community play fundamental roles in driving organic carbon accumulation and decomposition. This study found that Olsen-P and soil organic matter tended to be higher in rhizosphere soil than in bulk soil, although the difference was not statistically significant. This may have been due to microbial activity differing between rhizospheric and bulk soil, probably associated with root morphology and exudates. An incubation experiment of litter of different plant species mixed with soil showed that plant litter could significantly change soil chemistry, and this varied between plant species. Plant litter reduced soil acidity and increased soil Olsen-P, but this differed in magnitude between plant species. Soil concentrations of NO3-N and NH4-N decreased after incubation; it is argued this might result from microorganism consumption of soil organic carbon. This research also aimed to evaluate finding of an earlier study on the role of seabird guano on soil nutrient concentrations and the accumulation of nutrients in New Zealand flax (Phormium tenax). The present study indicated that there was no significant difference in soil P levels under flax compared to other plants, contradicting the earlier findings of Zhong (2016). It was suggested that the variation in P levels were more likely to be due to soil age and location differences. Furthermore, P. tenax was found to have a significantly higher concentration of sodium than other plants, suggesting its ability to absorb substantial amounts of sodium from the soil. The findings also raise the question of whether P. tenax captures sodium in cuticular wax from marine spray due to its morphological features, which could be explored in further research. Overall, this study has shown that soil and plant nutrients differ between plant species and that plants have significant effects on soil chemistry. Plant and soil nutrients interact with litter quality and other environmental factors. It is concluded that understanding soil biogeochemistry has a role to play in ecological restoration, although this is currently poorly understood.

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