14,250 results for Doctoral

  • Characterization of Groundwater with Complementary Age Tracers

    Beyer, Monique (2015)

    Doctoral thesis
    Victoria University of Wellington

    Groundwater age or residence time is the time water has resided in the subsurface since recharge. Depending on the application, this definition may or may not include travel through the unsaturated zone. The determination of groundwater age can aid understanding and characterization of groundwater resources, because it can provide information on e.g. groundwater mixing and flow, and volumes of groundwater and recharge. Groundwater age can be inferred from environmental tracers, such as SF₆ and tritium, that have a known input to groundwater and/or undergo known alteration processes in groundwater. The currently used age tracers face limitations regarding their application range and reliability. For example, some age tracers have local sources that can lead to contamination of groundwater. This contamination can result in misleading estimates of age. Other tracers have ambiguous inputs to groundwater, which can result in ambiguous age estimations. To reduce these limitations, it is now recognized that multiple tracers should be applied complementarily. There is also a need for new groundwater age tracers and/or new groundwater dating techniques to supplement the existing ones. Cost-effective and easily applicable tracers/techniques are preferred, since most established groundwater dating techniques are very costly and/or complex. Commonly measured hydrochemistry parameters , such as the concentrations of major ions and pH, have been suggested as cost-effective and easily determinable potential age tracers. To date, the use of commonly measured hydrochemistry parameters as independent age tracer has only been demonstrated for water recharged weeks to months ago relying on seasonal changes. Other studies applied commonly measured hydrochemistry complementarily to established age tracers to better constrain groundwater age and/or better understand and predict anthropogenic effects on groundwater quality. Further study is needed to assess the extent to which commonly measured hydrochemistry can be used to reduce uncertainty in tracer-inferred age as well as the extent to which commonly measured hydrochemistry can be used to extrapolate tracer-inferred age. In addition to tracer specific limitations, quantification of uncertainty and ambiguity is not standard in age modelling. Although a few studies have attempted to quantify uncertainty in age modelling with the aid of probabilistic approaches, their methods are often relatively complex and not transferrable to the many cases with little available data. Uncertainties in the tracer’s recharge estimate and identification of appropriate model components, such as the objective function, have not been considered. Studies in other areas of hydrological modelling, where probabilistic approaches are more commonly used, have highlighted the need for careful identification of model components.

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  • Comparing group-based interventions in older adults with subjective memory difficulties : a dissertation presented in partial fulfilment of the requirements for the degree of Doctorate in Clinical Psychology, Massey University, Wellington, New Zealand

    Sothieson, Veena (2014)

    Doctoral thesis
    Massey University

    The trend internationally and within New Zealand is of an increasing aging population, with numbers of those with dementia projected to increase rapidly. One way to address this issue is to consider the practical and clinical benefits of running memory intervention groups for older adults with memory difficulties/impairment. The current study intended to address some of the limitations found in memory intervention literature by (a) using a social control group as a control comparison, which has not been done before, and (b) separating out components of memory training interventions (i.e., memory strategies and lifestyle education). Therefore, the aim was to determine the extent to which receiving Memory intervention separately from a Lifestyle Education intervention would affect memory functioning in older adults with subjective memory difficulties, when compared with a social control condition. Participants for the intervention group were recruited from rest homes and retirement villages, while social control participants were community-dwelling older adults already taking part in weekly community group activities. A brief cognitive screen and subjective outcome measures were administered at baseline, post Phase 1, post Phase 2, and at six month follow-up. Quantitative and qualitative information from a total of 13 participants were analysed. Results from each of the outcome measures across the four time points indicated that there were no significant benefits of receiving Memory and/or Lifestyle Education interventions, when compared with a social control condition. However, a small sample size, non-equivalent groups, and lack of random assignment were some of the limitations which made it difficult to reach definite conclusions. Content analysis of qualitative information following intervention sessions provided some valuable considerations for running memory groups in future. In light of its limitations, the current study highlights practical considerations and recommendations for future research in this area. In particular, it identifies the value of conducting memory intervention research with older adults in residential care settings.

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  • Chicory (Cichorium intybus) and plantain (Plantago lanceolata); physiological and morphological responses to water stress, defoliation, and grazing preference with implications for the management of the Herb and Legume Mix : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Plant Science, Massey University, Te Kunenga ki Pūrehuroa, New Zealand

    Cranston, Lydia Margaret (2014)

    Doctoral thesis
    Massey University

    Herb and legume sward mixes containing chicory (Cichorium intybus), plantain (Plantago lanceolata), red clover (Trifolium pratense) and white clover (T. repens) are being increasingly used by farmers to improve animal performance compared to perennial ryegrass and white clover swards. However, little is known about the agronomic properties of this Herb and Legume Mix. The objectives of this research were to examine key factors likely to affect the success of the Herb and Legume Mix as a perennial sward mix. This thesis included a series of glasshouse experiments, a grazing experiment (examining plant parameters and animal grazing preference) and a mowing experiment. The glasshouse experiments indicated that chicory and plantain have different strategies for coping with moisture stress. The results suggest plantain may be more productive under moderate drought due to its greater shoot mass fraction, whereas chicory may be more productive and persistent under severe drought due to its greater root mass and taproot diameter. The Herb and Legume Mix accumulated greater annual dry matter when removed under Hard grazing (post-grazing residual of 4cm) compared to Lax grazing (post-grazing residual of 8cm). Hard grazing favoured plantain growth and persistence, while Lax grazing favoured red clover growth and resulted in chicory with a larger taproot diameter. It was concluded that grazing management decisions should be determined by ensuring optimal management of chicory. Ewe lambs displayed grazing preference for species within the Herb and Legume Mix; however this varied between seasons and was affected by the species availability, vertical access and palatability. The Herb and Legume Mix had a greater herbage nutritive value than the ryegrass and white clover sward and had a more stable composition over time than pure swards of chicory and plantain under a wide range of defoliation regimes. The results suggest the Herb and Legume Mix might be a more flexible perennial forage option than pure swards of chicory and plantain. Overall the results of this thesis indicated that the Herb and Legume Mix can be successfully utilised in most New Zealand grazing systems as a perennial forage sward.

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  • Increased intake of vegetables, herbs and fruit : effects on bone in postmenopausal women : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science, Massey University, Manawatu, New Zealand

    Gunn, Caroline Ann (2013)

    Doctoral thesis
    Massey University

    Dietary approaches to address bone loss at midlife usually involve supplementation or fortification. We aimed to investigate a food based approach to reduce bone turnover in post-menopausal (PM) women in two studies. In the first study, we investigated whether daily inclusion of specific vegetables attributed with bone resorbing inhibiting properties was feasible. We hypothesised increased intake of fruit/vegetables to ≥9 servings/day would lower potential renal acid load (PRAL) significantly (~20mEq/day) and increase urine pH (0.5 pH units) sufficiently to affect bone markers. The results of the first study confirmed the feasibility of daily inclusion of specific vegetables, reduction in renal acid load and increased urine pH. The subsequent Scarborough Fair Study (SF) used a randomised, active comparator design to increase specific vegetable/herb/fruit intake in two groups (A and B) of 50 PM women, from ≤ 5 servings/day to ≥ 9 servings/day for 3 months while a control group consumed their usual diet (n=43). Primary outcome variables were plasma bone markers which were assessed at baseline, six weeks and twelve weeks. Secondary outcome variables were plasma inflammation markers including adiponectin, urinary electrolytes (calcium, magnesium, potassium and sodium) and dietary intake assessed at baseline and 12 weeks and urinary pH assessed twice weekly. Increased intake of vegetables/herbs/fruit reduced P1NP and CTX (osteopenia) in Group B (SF) and urinary calcium loss in both intervention groups A and B (SF) with reduced PRAL. Adiponectin, tumour necrosis factor, interleukin 6 and 10 reduced in all groups. This study showed the SF vegetables/herbs/fruit may influence bone turnover and inflammatory markers. Few human intervention studies demonstrate reduction in plasma bone resorption markers with diet. Even fewer studies demonstrate reduction without supplementation with calcium, vitamin D, alkaline substrates, concentrated extracts or consumption of large quantities of a single functional food. The SF vegetables/herbs/fruit may protect against high bone turnover and subsequent bone loss in women with osteopenia and may have possibilities as an adjuvant to pharmaceutical therapies or a holistic dietary approach to reduce bone turnover and bone loss. Trial registration ACTRN 12611000763943

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  • Improving the response to synchronisation programmes of dairy cattle : a thesis presented in partial fulfilment of the requirement for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Palmerston North, New Zealand

    Sahu, Santosh Kumar (2014)

    Doctoral thesis
    Massey University

    A gonadotrophin, prostaglandin, gonadotrophin + progesterone (GPG+P4) programme with fixed-time artificial insemination (FTAI) is the current recommended synchronisation programme for both heifers and anoestrous cows on New Zealand dairy farms. However, it is an expensive programme and a better understanding of the role of all of its components would be very useful in developing alternative cheaper programmes. The two components of the programme that are the least understood, in terms of their underlying physiological actions and how they influence the outcome of synchronisation, are the Day 0 gonadotrophin-releasing hormone (GnRH) injection and the progesterone device. Additionally it is well known that energy status has a significant impact on fertility but there is little evidence, particularly under New Zealand conditions, of how energy status affects the response to GPG-based treatments in anoestrous postpartum dairy cows. The effects of a GPG (Day 0: 100 µg GnRH, Day 7: 500 µg PGF2a, Day 9: 100 µg GnRH) programme upon follicular and luteal dynamics, ovulation synchronisation and patterns of oestradiol and progesterone secretion in postpartum anoestrous dairy cows and nulliparous dairy heifers were compared with (i) a GPG programme plus a progesterone insert from Days 0–7 (GPG+P4) and (ii) a GPG+P4 programme from which the first GnRH treatment had been omitted (P+G+P4). Interactions of each treatment with energy balance, as determined by NEFA, IGF-I and insulin concentrations, were also studied in postpartum anoestrus cattle. Finally the conception rate (CR) to fixed time AI of a GPG+P4 programme in which AI was done concurrent with the Day 9 GnRH injection (Cosynch) was compared with a progesterone + prostaglandin programme (P4+PG; Day 0–7: progesterone releasing intravaginal device, morning of Day 6: 500 µg PGF2a, afternoon of Day 9: FTAI) in heifers. The physiological effects of the GPG and the GPG+P4 programmes were similar in anoestrous dairy cows. The inclusion of the Day 0 GnRH still appeared feasible in a GPG programme for treating anoestrous cows as it led to a higher probability of a corpus luteum (CL) on Day 7. In addition, treatment response was significantly affected by the postpartum duration and negative energy balance as evidenced by the significantly higher NEFA concentrations on Days 0, 7 and 9, and a lower insulin concentration on Day 0, in cows that failed to ovulate in response to the synchronisation protocol compared with cows that did ovulate. A clear and significant relationship between NEFA concentrations and ovulation in response to all synchronisation protocols showed that, regardless of the regimen that was used to treat anoestrus, the response was moderated and limited by the degree of negative energy balance. In heifers, the removal of the progesterone-releasing device from a GPG+P4 programme had no effect on follicular dynamics or on the proportion of heifers which ovulated after either the GnRH injection on Day 0 or Day 9. Additionally, unlike the anoestrus cows, omitting the GnRH injection on Day 0 did not result in significantly delayed ovulation at the end of the programme, inasmuch as treatment with P+G+P4 was associated with earlier ovulation than GPG. Furthermore, synchronising heifers with a significantly less expensive programme (P4+PG) resulted in similar CR to synchronising with GPG+P4 (54.8% versus 52.4%, respectively) further confirming that Day 0 GnRH was not essential in heifer synchrony. In conclusion, the higher conception rate in cows treated with a GPG+P4 programme rather than a GPG programme reported previously does not seem to be modulated by the actions on follicular dynamics and improved synchronised ovulation in dairy cattle with postpartum anoestrous (or in nulliparous heifers); however, the treatment response in anoestrous cows can be significantly affected by negative energy balance. In contrast, in dairy heifers, no benefit of Day 0 GnRH or the progesterone device in a GPG+P4 programme suggests the possibility of more cost effective options (e.g. P4+PG) which can lead to a CR as high as those synchronised using a GPG+P4 programme.

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  • Measurement of true ileal phosphorus digestibility in feed ingredients for poultry : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Poultry Science at Institute of Veterinary, Animal and Biomedical Sciences (IVABS), Massey University, Palmerston North, New Zealand

    Mutucumarana, Ruvini Kamalika (2014)

    Doctoral thesis
    Massey University

    Global interest in improving the utilisation of phosphorus (P) by poultry has recently increased due to concerns over environmental pollution through excess P excretion, depletion of non-renewable inorganic phosphate deposits, and increasing price of inorganic phosphate supplements. Use of a sound criterion, preferably based on P digestibility, to assess P availability is needed to enable greater efficiency of utilisation of dietary P. No established methodology is currently available to measure the true digestible P contents in common feed ingredients for poultry. The first experiment of this thesis (Chapter 3) investigated the effects of dietary calcium (Ca) concentrations (6, 9 and 12 g/kg) on the digestibility of P, Ca, nitrogen, fat and starch in different intestinal segments and on the apparent metabolisable energy of diets in young broiler chickens. The results showed that the digestion of P and Ca was completed by upper ileum and jejunum, respectively. The site of digestion of P and nitrogen was found to shift depending on the dietary Ca concentrations. The digestibility coefficients of P in low, normal and high Ca diets at the lower ileum were determined to be 0.417, 0.379 and 0.325, respectively. The overall data showed that increasing dietary Ca concentrations negatively influenced the digestion of P, nitrogen and fat, but had no effect on those of Ca, starch and apparent metabolisable energy. The second experiment (Chapter 4) was conducted to determine endogenous losses of P and Ca in broiler chickens. The data showed that the ileal endogenous P losses in birds differed depending on the methodology employed. The ileal endogenous flow of P in birds fed P-free, gelatin-based and casein-based diets were 25, 104 and 438 mg/kg dry matter intake (DMI), respectively. Ileal endogenous flow of Ca in birds fed casein-based diet was estimated to be 321 mg/kg DMI. The next three experiments (Chapters 5, 6 and 7) investigated the potential usefulness of regression method to evaluate true ileal P digestibility of seven feed ingredients. True ileal P digestibility coefficients of maize, canola meal, wheat, sorghum, soybean meal and maize-distiller‟s dried grains with solubles for broiler chickens were determined to be 0.676, 0.469, 0.464, 0.331, 0.798 and 0.727, respectively. For plant-based ingredients, the determined true digestible P values were consistently higher than corresponding non-phytate P values (Maize, 1.72 vs. 0.75; canola meal, 4.55 vs. 2.82; wheat, 1.49 vs. 1.11; sorghum, 0.78 vs. 0.55; soybean meal, 5.16 vs. 2.15; maize-distiller‟s dried grains with solubles, 5.94 vs. 4.36 g/kg, as fed ii basis, respectively). Phytate P in maize (54.25%), soybean meal (69.7%) and maize- distiller‟s dried grains with solubles (41.5%) were well digested by broilers compared to canola meal (25.2%), wheat (18.1%) and sorghum (13.0%). True ileal P digestibility coefficients of three meat and bone meal (MBM) samples ranged from 0.420 to 0.693. Total and true digestible P contents of three MBM samples (MBM-1, MBM-2 and MBM-3) were determined to be 37.5 and 26.0; 60.2 and 36.6; and 59.8 and 25.1 g/kg, as fed basis, respectively, suggesting that P in MBM is not highly digestible. The overall data suggested that the use of regression approach to estimate true ileal P digestibility in feed ingredients has number of limitations. Overestimation as a result of using Ca- and P-deficient diets and the negative endogenous P losses observed for some ingredients (canola meal, sorghum and MBM-3) were main concerns. Negative ileal endogenous P losses were also shown to be associated with low true ileal P digestibility in these ingredients. In the final experiment (Chapter 8), two regression-based methodologies were compared for the measurement of true ileal P digestibility in maize and soybean meal. The results showed that the methodology influenced P digestibility in maize and soybean meal. The use of assay diets containing a narrow Ca:total P ratio yielded higher P digestibility for both ingredients. In this thesis research, the regression method was used to determine true ileal P digestibility of ingredients, but this approach suffers from several drawbacks. The data reported in this thesis also demonstrated that high dietary Ca concentrations were detrimental to the digestibility of nutrients, particularly of P, nitrogen and fat.

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  • The impact of post-exercise protein-leucine ingestion on subsequent performance and the systematic, metabolic and skeletal muscle molecular responses associated with recovery and regeneration : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy (Health), Massey University

    Nelson, Andre Richard (2012)

    Doctoral thesis
    Massey University

    The objective was to determine the effect of post-exercise protein-leucine coingestion with carbohydrate and fat on subsequent endurance performance and investigate whole-body and skeletal-muscle responses hypothesised to guide adaptive-regeneration. Methods. Study-JA Twelve trained-men ingested protein/leucine/carbohydrate/fat (20/7.5/89/22 g· h- 1 ) or carbohydrate/fat (control, 119/22 g· h- 1 ) supplements after intense cycling over six days. Glucose and leucine turnover, metabolomics, nitrogen balance and performance were examined. Study-] B Immune-function responses to supplementation were investigated via neutrophil 0 2- production, differential immune-cell count, hormones and cytokines. Study-2A Twelve trained-men ingested low-dose protein/leucine/carbohydrate/fat (23 .3/51180/30 g), high-dose (70115/180/30 g) or carbohydrate/fat control (274/30 g) beverages following 100- min of intense cycling. Vastus lateralis biopsies were taken during recovery (30-min/4-h) to determine the effect of dose on myofibrillar protein synthesis (FSR), and mTOR-pathway activity infened by western blot. Study-2B The transcriptome was intenogated to determine acute-phase biology differentially affected by protein-leucine dose. Results. Protein-leucine increased day-1 recovery leucine oxidation and synthesis, plasma and urinary branch-chain amino acids (BCAAs), products of their metabolism, and neutrophil-priming plasma metabolites versus control. Protein-leucine lowered serum creatine kinase 21-25% (±90% confidence limits 14%) and day 2-5 nitrogen balance was positive for both conditions, yet the impact on sprint power was trivial. Protein-leucine reduced day-1 neutrophil 02- production (15-17 ±20 mmol·02-·celr1 ) but on day-6 increased post-exercise production (33 ±20 mmol·02-·celr1 ) having lowered pre-exercise cortisol (21% ±15%). The increase in FSR with high-dose (0.103%· h-1 ± 0.027%· h-1 ) versus low-dose (0.092%· h-1 ± 0.017%· h-1 ) was likely equivalent. High-dose increased serum insulin (1.44-fold x/+90% confidence limits 1.18), 30- min phosphorylation ofmTOR (2.21-fold x/+1.59) and p70S6K (3.51-fold x/+1.93), and ii 240-min phosphorylation of rpS6 ( 4.85-fold x/-d .37) and 4E-BP1-a (1.99-fold x/-d .63) versus low-dose. Bioinformatics revealed a biphasic dose-responsive inflammatory transcriptome centred on interleukin (IL)-1~ at 30-min (high-dose) and IL6 at 240-min (highdose, low-dose) consistent with regulation of early-phase myeloid-cell associated muscle regeneration. Conclusions. Protein-leucine effects on performance during intense training may be inconsequential when in positive nitrogen balance, despite saturating BCAA metabolism, protein synthesis, and attenuating cell-membrane damage. 24 g of protein and 5 g leucine near saturated post-exercise myofibrillar FSR and simulated an early inflammatory promyogenic transcriptome common to skeletal muscle regeneration that was accentuated with 3-fold higher protein-leucine dose.

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  • Short circuit co-evolution by the perfect parasites : antifreeze glycoproteins in Antarctic fish leeches (Hirudinea, Piscicolidae) : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Zoology at Massey University

    Kolb, Jürgen Bertram (2013)

    Doctoral thesis
    Massey University

    Antifreeze glycoproteins (AFGPs) play an important role in biochemical adaptation to supercooled waters and hence in the survival of notothenioid fish in Antarctica. These fishes have a well developed parasitic epifauna, which in turn is also exposed to freezing conditions. In order to retain their association with Antarctic fishes as the environment progressively cooled during the Miocene, leeches as fish-associated ectoparasites had either (i) to evolve a short circuit mechanism to acquire the necessary life-saving chemical compounds from their host, (ii) to adapt their own genome to confer protection from freezing, or (iii) to develop a combined tactic unique to their parasitic life strategy according to requirements during ontogenesis. I have found that Antarctic leeches (Hirudinea, Piscicolidae), that feed on a variety of notothenioid fish species, contain antifreeze compounds at the cellular level. I present evidence that strongly indicates an absorption pathway of AFGPs in the parasitic organisms from the fish blood as source. The physiological processes of AFGPs uptake from the intestine and circulatory distribution by haemolymph would be analogous to those enabling the fish hosts to distribute these peptides by blood within their bodies, as fish absorb AFGPs through the gut after production in the pancreas. The analysis of protein chemical structures in leech material revealed characteristics typical of fish AFGPs. Further, there are high capacities for freezing point suppression in vivo, thus biological activity of antifreeze proteins in the leech parasites Cryobdella antarctica and Cryobdella levigata. A combination of this thermal hysteresis (TH) with a specific bi-pyramidal ice crystal growth has been observed, which is typical for fish AFGPs. This confirms the presence not only of functional antifreeze macromolecules but also of true AFGPs in these parasite species. Finally, to trace the potential origin of these proteins to leech genomic information, mRNA molecules were successfully detected in C. levigata, as the intermediate step necessary for any de novo AFGP biosynthesis. These results suggest the possibility of a vi horizontal gene transfer (HGT) event in this host-parasite system and if proven would mark a further record of such a gene transfer for antifreeze molecules in Antarctica but for the first time outside the surface sea ice zone. I conclude that Antarctic fish leeches have developed a novel means of an evolutionary shortcut by co-opting mechanisms for survival in supercooled waters from their hosts in the form of biochemical exploitation and possibly in addition by HGT. To the best of my knowledge, the use of functional AFGPs after digestive absorption would represent the first example in the animal kingdom of an instantly effective adaptive advantage provided by another species under natural conditions in a quasi short circuit co-evolution. I also present results from a first survey on the leech fauna in the Ross Sea across nine species of Antarctic fishes and report one new host record for C. antarctica and three new leech-host associations for C. levigata. Finally, one new species belonging to the Piscicolidae is described, Megapodibdella kirsteni, gen. et sp. nov., from the Antarctic eelpout Lycodichthys dearborni.

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  • E kore au e ngaro, he kakano ahau : whakapapa sharing in the context of therapy : a thesis presented in partial fulfilment of the requirements for a Doctorate in Clinical Psychology at Massey University, Wellington Campus, New Zealand

    Mitchell, Arna (2014)

    Doctoral thesis
    Massey University

    Maori experience disproportionately negative outcomes in mental health in New Zealand. The adaptation of therapeutic assessments and interventions to allow more culturally appropriate work with Maori occurs, however, little research promoting an understanding of client’s experience of these adaptations exists. One such adaptation is the sharing of whakapapa (genealogy) between therapist and client. Whakapapa sharing involves a level of therapist self disclosure not yet investigated in psychological literature. This Maori centred analogue study investigates the client’s experience of whakapapa sharing during the first session of therapy. A mixed, between and within subjects design was used, both quantitative and qualitative data were collected and analysed. 30 Maori women between the ages of 18 and 40 participated in two sessions of Acceptance and Commitment Therapy, participants were allocated to either a Whakapapa Sharing group or a Therapist Non-Disclosure group. All participants completed questionnaires measuring the therapeutic alliance, therapy expectancy, outcome of therapy and a cultural questionnaire measuring participant knowledge of their own whakapapa. Participants from the Whakapapa Sharing group also reported on their experience of the sharing. Quantitative analyses revealed no group differences in either the therapeutic relationship measure or the outcome measure. All participants from the Whakapapa Sharing group, regardless of their level of knowledge of their own whakapapa, reported the whakapapa sharing as a positive experience. Further analysis of the qualitative data revealed five main themes; the whakapapa sharing process reported to promote engagement, was perceived as important for Maori, allowed the establishment of connections between therapist and client, provided clients with information with which to form judgements about the therapist and the sharing was seen to be an equitible experience. These themes were arranged into a theoretical model, in which, all five were hypothesised to have a relationship with the power imbalance inherent between therapist and client. Whereby four of the themes were hypothesised to contribute to a decrease in the imbalance of power and the final theme was seen as a result of the decrease in the power imbalance. These tentative findings suggest that the exchange of whakapapa between a therapist and client may serve to decrease the power imbalance in the therapeutic relationship, and as such, it is an appropriate process of engagement in a therapeutic setting with Maori clients, who often experience marginalisation.

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  • The evaluation of the Transformers programme : an emotion regulation programme for people who have an intellectual disability : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Clinical Psychology at Massey University, Wellington, New Zealand

    McWilliams, Jenna Louise (2014)

    Doctoral thesis
    Massey University

    It is widely accepted that emotion regulation difficulties are common in people who have an intellectual disability. Not being able to manage their distressing emotions can lead to challenging behaviour such as verbal and physical violence and property destruction and can lead to injury, alienation, poor-self-esteem, and legal problems. Growing research suggests that people who have an intellectual disability have the ability to engage in and benefit from interventions that address their emotion regulation problems. The current thesis consists of four papers—a systematic literature review, programme description, a study regarding emotional identification, and a study about emotion regulation. The main aim of the research was to evaluate an emotion regulation programme known as Transformers that is being implemented at an intellectual disability service. Transformers is a group-based treatment programme that is run over a six-month period. Five participants with mild to moderate intellectual disability (aged 17-42 years) attended the Transformers programme and took part in the studies along with their caregivers. A single-case design was chosen to evaluate the effectiveness of the programme. Participants completed emotion recognition tasks and self-report measures of emotion regulation before, during, and after their involvement in the programme. Caregivers also rated the frequency of participants’ use of emotion regulation skills and incident reports provided insight into their ongoing behaviour. While the results showed that the Transformers programme was not effective in improving participants’ abilities to recognise emotion nonetheless participants did increase in their ability to use appropriate emotion regulation strategies and reduced the number of incidents of challenging behaviour. Overall, these preliminary findings suggest that the Transformers programme is a viable treatment option for people who have an intellectual disability who have difficulty managing their own emotions. While the findings are encouraging, it is recommended that further research be carried out using larger sample sizes and longer follow up periods to establish the effectiveness of the programme.

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  • Dietary titanium dioxide particles and intestinal health : a thesis submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Nutritional Science at Massey University, Manawatu, New Zealand

    Riedle, Sebastian (2014)

    Doctoral thesis
    Massey University

    The purpose of this dissertation was to investigate the relationship between food-grade titanium dioxide particles and intestinal health, in particular the development of Crohn’s disease after uptake of titanium dioxide particles in intestinal lymphoid tissues. Crohn’s disease is a common form of inflammatory bowel disease. It is characterised by chronic inflammation of the gastrointestinal tract and affects approximately 1 in 1,000 people. The aetiology of Crohn’s disease is unclear, but both genetic and environmental factors are involved in the development of the disease. The gene that is most commonly associated with Crohn’s disease is the nucleotide-binding oligomerisation domain (NOD) 2 gene. The diet is one of the most likely environmental factors that have been proposed to play a role in Crohn’s disease. It has been hypothesised that uptake of titanium dioxide particles, which are used as a whitening agent in processed foods, toothpaste, and pharmaceuticals, by macrophages in intestinal lymphoid tissues negatively affects intestinal health and contributes to the development of Crohn’s disease. To investigate this hypothesis, immune cell-stimulating properties of titanium dioxide were first assessed in vitro with macrophages derived from wild-type mice and mice with a Crohn’s disease-like Nod2 gene variant. These mouse models were also used to determine particle uptake in intestinal lymphoid tissues in vivo after exposure to titanium dioxide with the diet and effects of this dietary exposure on intestinal health and urine metabolites. The results from the in vitro studies showed that titanium dioxide induced the release of the pro-inflammatory cytokine interleukin-1β. For the first time, it has been shown that accumulation of particles in intestinal lymphoid tissues was a consequence of titanium dioxide intake with the diet. However, this had no negative effects on growth performance and intestinal health of both wild-type mice and mice with a Crohn’s disease-like Nod2 gene variant. Nevertheless, differences in urine metabolite profiles between wild-type mice exposed to titanium dioxide and unexposed wild-type mice indicated that consumption of a titanium dioxide-containing diet affected the metabolism. This dissertation forms the foundation for future studies with animal models about the relationship between titanium dioxide and intestinal health.

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  • Maternal exercise during pregnancy affects the rat musculoskeletal system and indices of energy metabolism : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Manawatū, New Zealand

    Rosa, Brielle Vastola (2013)

    Doctoral thesis
    Massey University

    The developmental origins of health and disease hypothesis postulates that environmental cues perceived by the developing organism during early life program long-term health outcomes. A series of studies were undertaken to examine the developmental programming effects of maternal exercise during pregnancy on offspring musculoskeletal health and energy metabolism using a rat model. Firstly, an exercise that did not cause a potentially confounding stress response in the exercising animal was identified. Secondly, pregnant dams then performed this exercise and its effects on fetal growth and the maternal stress response were quantified. Finally, the offspring of dams that exercised throughout pregnancy were allowed to grow to maturity, and the effects of maternal exercise on their musculoskeletal health and energy metabolism were assessed. Throughout these experiments, body composition was assessed by dual- energy X-ray absorptiometry, and tibial parameters were measured using peripheral quantitative computed tomography. Maternal stress was quantified by measurement of faecal corticoid metabolites. Serum concentrations of the fully and undercarboxylated forms of the bone-derived hormone osteocalcin, and expression of genes related to osteocalcin carboxylation, were measured to explore their role in the response of offspring bone and energy metabolism to maternal exercise. Two exercise types, rising to an erect bipedal stance and tower climbing, were initially tested in non-pregnant rats. Both rapidly caused changes in the tibias of exercised animals without inducing stress. In pregnant rats, both exercises increased fetal growth relative to controls, and neither caused a physiological stress response in the dams. Since rising to an erect bipedal stance had the greater effect on fetal growth, it was selected for use in the final study in which the offspring were grown to maturity. Maternal exercise throughout pregnancy was associated with sex-dependent changes in the bone and body composition of the mature offspring. Male offspring of exercised dams had increased adiposity and serum undercarboxylated osteocalcin concentrations, while offspring of both genders had lower volumetric bone mineral density at the tibial diaphysis, relative to controls. These results suggest that maternal exercise has long- term effects on the musculoskeletal system and energy metabolism, and that undercarboxylated osteocalcin may play a role in these effects.

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  • Achieving positive stepfamily relationships : negotiating fairness, forgiveness, and acceptance : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Psychology at Massey University, Wellington, New Zealand

    Falchi, Celia Noreena (2014)

    Doctoral thesis
    Massey University

    Instructional DVD (Appendix H) available with hard copy in the library

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  • Planning for a night out : local governance, power and night-time in Christchurch, New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Resource and Environmental Planning at Massey University, Turitea, Aotearoa, New Zealand

    Johnston, Karen Marie (2014)

    Doctoral thesis
    Massey University

    This research explores the changing nature of local governance and how power is exercised within Christchurch City Council’s decision-making process of its revitalisation of the Central Business District (CBD). A governmentality theoretical framework extends the scholarly debate on local government decision-making and allows for the exploration of social relations and lived realities of young people who use the night-time spaces created by the CBD revitalisation process. Three research questions structure the thesis: how is power exercised during CBD decision-making processes within Christchurch City Council?; what governmental technologies are adopted by Christchurch City Council to revitalise the CBD between 1999 and 2010?; and, what are the lived realities of the young people who use the revitalised spaces of the CBD? Christchurch, New Zealand’s second largest city, is the case study because of its recent CBD revitalisation and the significant changes to its decision-making processes. These changes impact on the way revitalisation is executed. The decision-making process of CBD revitalisation is examined through a qualitative methodology. Methods involved: document analysis; observations; individual, semi-structured interviews (with elected and non-elected local government representatives, business people, and police); and, focus-group interviews with young people who enjoy the CBD night-time entertainment spaces. There are three key research findings. First, power is simultaneously dispersed to an outside organisation and concentrated within the Council in fewer people. Particular actors have significant influence over decision-making. Second, governing at a distance occurs using technologies of a key stakeholder group followed by changes to internal Council decision-making. A post-political turn emerged where consensus is encouraged and political dissent discouraged. Third, the revitalisation project is successful in the creation of a vibrant night-time economy where young people drink and socialise. Paradoxically, these new subjects are constituted through the revitalised spaces as a problem, bringing into stark relief the conflicts between public and private interests in Christchurch’s CBD revitalisation. This research offers new possibilities for planning scholars. Governmentality allows for the critical examination of power in local governance with the explicit inclusion of the lived realities of the subjects of that governance.

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  • Effect of mechanical work on the meat used for making reformed meat products : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Technology at Massey University, Palmerston North, New Zealand

    Mohammad Rashedi, Ismail Fitry (2014)

    Doctoral thesis
    Massey University

    Tumbling, a process commonly used during production of reformed meat, applies mechanical work against the meat pieces to break down the meat structure, enhance brine absorption and extract solubilized myosin to the meat surface. The myosin acts as glue to bind meat pieces together when heated. The work done in the tumbler is currently unquantifiable and its relationships with total protein and myosin extraction and binding strength (Tensile Adhesive Strength, TAS) of two meat pieces are unknown. Much of this project was allocated to developing and evaluating an instrument called the Impact and Friction Mechanical Robot (IFMR), which is able to repeatedly apply a desired impact and to vary the rate of repeated impacts and the time gap between each impact. The degree of sample compression could also be varied. The work done as a consequence of the hitting process can be calculated for each individual hit and summed to give the total work impacted on the meat. Four groups of 20 mm3 meat cubes were prepared for the hitting treatments. One group was used as the control while the other three were pre-soaked in 0.396, 0.713 or 1.146 mol/L of brine consisting of NaCl and salts of phosphate. The meat cubes were hit so maximum impact force was 10 N with an average 0.665 s between each hit for 0, 400, 800, 1200, 1600 or 2000 hits. The exudate on the hit meat surface was scraped off and examined for total protein and myosin. The total protein extracted was not influenced by the work (p=0.764) applied on meat cubes pre-soaked in different concentrations of brine (p=0.123). Myosin extracted increased with total work done (p=0.006) on the meat and concentration of brine (p<0.001) for pre-soaking. The TAS also increased as myosin concentration increased (p=0.001). A good TAS of the meat pieces could be achieved by adequately solubilising the myosin using brine and applying sufficient total work to the meat pieces.

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  • Structure and function of the eukaryotic ADP-dependent glucokinase : a dissertation presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Biochemistry, Massey University, Manawatu, New Zealand.

    Richter, Jan Paul (2014)

    Doctoral thesis
    Massey University

    The ADP-dependent glucokinase enzymes (ADPGK) are the first new glycolytic enzymes to be discovered in over 40 years. This class of enzymes was first described in thermophilic archaea in 1994. A decade later, an ADPGK from a eukaryote was also identified and characterised. The ADPGK enzymes catalyse a phosphorylation reaction converting glucose and ADP to glucose-6-phosphate and AMP. The enzyme is well studied in extremophilic archaea, where ADPGK is part of a set of glycolytic enzymes that use ADP instead of ATP for the phosphorylation of various sugars. However, ADPGK has also been found in the genomes of mesophilic species and higher eukaryotes, suggesting that the enzyme is not necessarily an adaption to high temperatures. In eukaryotes, ADPGK has been linked to a modified glycolysis pathway that is required for T-cell activation. While crystal structures of the archaeal ADPGKs are known, no structure of a eukaryotic ADPGK had been solved before the work undertaken in this thesis. In this thesis, the kinetic analysis of a recombinant form of Homo sapiens ADPGK and the crystal structure of a truncated form of Mus musculus ADPGK are presented. Both enzymes were expressed recombinantly in E. coli and purified in soluble form. The kinetic parameters determined for H. sapiens ADPGK proved to be comparable to the mouse enzyme, which had been published earlier. In addition, the phosphoryl acceptor specificity of H. sapiens ADPGK was extensively tested by 31P-NMR, where the enzyme proved to be highly specific for Dglucose. Residues important for catalysis have been modified by site-directed mutagenesis and the variants of H. sapiens ADPGK were purified and kinetic parameters determined. A single crystal was obtained from a truncated variant of M. musculus ADPGK, which diffracted to 2.1 Å. The structure of M. musculus ADPGK could be solved by molecular replacement using the known crystal structures of the archaeal ADPGKs for initial phasing. It proved to be quite similar to the archaeal, ADPGKs, despite the low sequence identity. The combined data in this work improves our understanding of the conservation of the structure-function relationship of eukaryotic ADPGKs.

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  • Data-parallel structural optimisation in agent-based modelling : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Computer Science at Massey University, Albany, New Zealand

    Husselmann, Alwyn Visser (2014)

    Doctoral thesis
    Massey University

    AGENT-BASED MODELLING (ABM) IS PARTICULARLY SUITABLE for aiding analysis and producing insight in a range of domains where systems have constituent entities which are autonomous, interactive and situated. Decentralised control and irregular communication patterns among these make such models difficult to simulate and even more so to understand. However, the value in this methodology lies in its ability to formulate systems naturally, not only generating the desired macroscopic phenomena, but doing so in an elegant manner. With these advantages, ABM has been enjoying widespread and sustained increasing use. It is then reasonable to seek advances in the field of ABM which would improve productivity, comparability, and ease of implementation. Much work has been done towards these, notably in terms of design methodology, reporting, languages and optimisation. Three issues which remain despite these efforts concern the efficient construction, performance and calibration of agent-based models. Constructing a model involves selecting agents, their attributes, behaviours, interaction rules, and environment, but it also demands a certain level of programming ability. This learning curve stymies research effort from disciplines unrelated to computer science. It is also not clear that one methodology and software package is suitable for all circumstances. Domain-specific languages (DSLs) make development much simpler for their application area. Agent-based model simulation sometimes suffer tremendously from performance issues. Models of situations such as algal cultivation, international markets and pedestrians in dense urban areas invariably suffer from poor scaling. This puts large system sizes and temporally distant states out of reach. The advent of scientific programming on graphical processing units (GPUs) now provides inexpensive high performance, giving hope in this area. It is also important to calibrate such models. More interestingly, the problem of calibrating model structure is given particular emphasis. This ambitious task is difficult for a number of reasons, and is investigated with considerable thought in this work. In summary, the research shows that appropriate use of data-parallelism by multi-stage programming in a simple domain-specific language affords high performance, extensibility and ease of use which is capable of effective automatic model structure optimisation.

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  • Learning Feature Selection and Combination Strategies for Generic Salient Object Detection

    Naqvi, Syed (2016)

    Doctoral thesis
    Victoria University of Wellington

    For a diverse range of applications in machine vision from social media searches to robotic home care providers, it is important to replicate the mechanism by which the human brain selects the most important visual information, while suppressing the remaining non-usable information. Many computational methods attempt to model this process by following the traditional model of visual attention. The traditional model of attention involves feature extraction, conditioning and combination to capture this behaviour of human visual attention. Consequently, the model has inherent design choices at its various stages. These choices include selection of parameters related to the feature computation process, setting a conditioning approach, feature importance and setting a combination approach. Despite rapid research and substantial improvements in benchmark performance, the performance of many models depends upon tuning these design choices in an ad hoc fashion. Additionally, these design choices are heuristic in nature, thus resulting in good performance only in certain settings. Consequentially, many such models exhibit low robustness to difficult stimuli and the complexities of real-world imagery. Machine learning and optimisation technique have long been used to increase the generalisability of a system to unseen data. Surprisingly, artificial learning techniques have not been investigated to their full potential to improve generalisation of visual attention methods. The proposed thesis is that artificial learning can increase the generalisability of the traditional model of visual attention by effective selection and optimal combination of features. The following new techniques have been introduced at various stages of the traditional model of visual attention to improve its generalisation performance, specifically on challenging cases of saliency detection: 1. Joint optimisation of feature related parameters and feature importance weights is introduced for the first time to improve the generalisation of the traditional model of visual attention. To evaluate the joint learning hypothesis, a new method namely GAOVSM is introduced for the tasks of eye fixation prediction. By finding the relationships between feature related parameters and feature importance, the developed method improves the generalisation performance of baseline method (that employ human encoded parameters). 2. Spectral matting based figure-ground segregation is introduced to overcome the artifacts encountered by region-based salient object detection approaches. By suppressing the unwanted background information and assigning saliency to object parts in a uniform manner, the developed FGS approach overcomes the limitations of region based approaches. 3. Joint optimisation of feature computation parameters and feature importance weights is introduced for optimal combination of FGS with complementary features for the first time for salient object detection. By learning feature related parameters and their respective importance at multiple segmentation thresholds and by considering the performance gaps amongst features, the developed FGSopt method improves the object detection performance of the FGS technique also improving upon several state-of-the-art salient object detection models. 4. The introduction of multiple combination schemes/rules further extends the generalisability of the traditional attention model beyond that of joint optimisation based single rules. The introduction of feature composition based grouping of images, enables the developed IGA method to autonomously identify an appropriate combination strategy for an unseen image. The results of a pair-wise ranksum test confirm that the IGA method is significantly better than the deterministic and classification based benchmark methods on the 99% confidence interval level. Extending this line of research, a novel relative encoding approach enables the adapted XCSCA method to group images having similar saliency prediction ability. By keeping track of previous inputs, the introduced action part of the XCSCA approach enables learning of generalised feature importance rules. By more accurate grouping of images as compared with IGA, generalised learnt rules and appropriate application of feature importance rules, the XCSCA approach improves upon the generalisation performance of the IGA method. 5. The introduced uniform saliency assignment and segmentation quality cues enable label free evaluation of a feature/saliency map. By accurate ranking and effective clustering, the developed DFS method successfully solves the complex problem of finding appropriate features for combination (on an-image-by-image basis) for the first time in saliency detection. The DFS method enables ground truth free evaluation of saliency methods and advances the state-of-the-art in data driven saliency aggregation by detection and deselection of redundant information. The final contribution is that the developed methods are formed into a complete system where analysis shows the effects of their interactions on the system. Based on the saliency prediction accuracy versus computational time trade-off, specialised variants of the proposed methods are presented along with the recommendations for further use by other saliency detection systems. This research work has shown that artificial learning can increase the generalisation of the traditional model of attention by effective selection and optimal combination of features. Overall, this thesis has shown that it is the ability to autonomously segregate images based on their types and subsequent learning of appropriate combinations that aid generalisation on difficult unseen stimuli.

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  • Teacher cognition about technology-mediated EFL instruction in the Thai tertiary context : a thesis presented in fulfilment of the requirements for the degree of Doctor of Philosophy in Second Language Teaching at Massey University

    Suwannasom, Thitirat (2010)

    Doctoral thesis
    Massey University

    Drawing on theories of teacher cognition and sociocultural frameworks, this study investigates Thai university English lecturers’ cognition about integrating Information and Communication Technology (ICT) in English language instruction and writing instruction in Thai tertiary contexts. A more specific goal is to investigate technology-using teachers’ personal principles and practices in their teaching contexts. The study was guided by the following research questions: What is the nature of Thai tertiary teacher cognition about the use of technology in EFL instruction? What is the nature of Thai tertiary teacher cognition about the use of technology in EFL writing instruction? How do Thai tertiary teachers perceive their practices and roles in relation to their technology-mediated EFL instruction in particular settings? In Thai tertiary education, what are the sociocultural aspects that shape teacher cognition and practice about technology-mediated EFL teaching? A teacher cognition questionnaire was designed and administered to 47 Thai EFL lecturers in seven public universities; semi-structured interviews and scenario-based tasks were conducted with seven lecturers; unstructured interviews and observations were carried out with three teachers who used technology in their classroom teaching in order to gain a better understanding of their situated perceptions about the use of technology in particular teaching and learning contexts. The results reveal that university EFL teachers’ views of technology are highly shaped by both their teaching environment and individual beliefs about English language learning. When teachers apply technology in their instruction, they also apply their personal principles or maxims that guide their practices. In addition, a number of sociocultural aspects emerged in teachers’ views about technology use in their EFL teaching contexts giving rise to theoretical implications about how teacher cognition is conceptualised. Some of the major implications for practice include: the need to encourage EFL teachers to reflect on their teaching principles relevant to their working contexts; the value of providing teachers with models of technology use in tertiary EFL teaching; and the maximisation of the use of available technology to support local practices. Implications for methodology include the use of multiple context-specific instruments and methods to elicit teachers’ underlying beliefs and perspectives about technology-mediated teaching.

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  • Thermophiles and fouling deposits in milk powder plants : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Food Engineering and Technology at Massey University, Palmerston North, New Zealand

    Hinton, Andrew Richard (2003)

    Doctoral thesis
    Massey University

    Fouling deposits were suspected of playing a pivotal role in the thermophile contamination problem experienced in the dairy industry during milk powder manufacture. The objective of this work was to investigate thermophile growth and develop an understanding of how fouling deposits affect thermophile contamination in milk powder plants. Pilot plant and laboratory scale studies were carried out investigating: The release of thermophiles from fouled and un-fouled surfaces; The survival of thermophiles in fouling during cleaning: The rate of re-contamination of thermal equipment after incomplete cleaning; and the adhesion of thermophiles to fouled and clean stainless steel. Thermophile contamination from the pilot plant equipment was also modelled mathematically. The bulk milk thermophile contamination from sanitised fouled and un-fouled surfaces was found to be not significantly different, showing that fouling deposits by themselves do not increase the steady state amount of bulk contamination and that the more important factor is the amount of surface area available for colonisation within the temperature growth range of the thermophiles. Milk fouling layers provided much greater protection against cleaning than that of biofilms alone. Thermophiles that survive cleaning or greater initial thermophile concentrations in the raw milk were shown to reduce the plant production time available before concentrations of thermophiles in the bulk milk became excessive (>1x10 6 cfu.ml-1). Therefore, cleaning procedures in milk powder plants need to remove or destroy all traces of thermophiles to allow the maximum possible run length. It is similarly important to obtain raw milk with the lowest possible thermophile load before processing. During adhesion studies, the number of thermophilic bacteria adhering to stainless steel surfaces increased with bulk cell concentration and increasing contact time for adhesion. The adhesion rate of thermophiles to whole milk fouling layers was found to be around ten times higher than the adhesion rate to stainless steel. Steady state modelling provided a quick estimate of the level of bulk milk contamination that can be expected, however it was dependent on obtaining accurate measurements of the surface numbers. Since surface numbers were underestimated by approximately a decade using techniques that dislodged but did not enumerate loosely adhered cells, the model under predicted the bulk milk contamination. Unsteady state modelling predicted the trends observed in the experimental data and provided reasonable estimates of the bulk contamination that can be expected over time from the pilot plant. Predictions from the model after changes in key parameters provide an insight to the magnitude of any reduction in contamination that can be made. The results of this work have demonstrated that thermopile contamination during dairy processing can be minimised through: Re/design operating equipment to minimise the residence time of the product in the range of 40-70°C. Minimising the contact surface area of thermal equipment by use of alternative direct heating technologies. Minimising fouling by management of milk quality, optimising processing conditions, hygienic design of the plant equipment and ensuring the product mix is suited to the plant. Ensuring that the plant is thoroughly clean at the commencement of each run through attention to equipment design and optimisation of cleaning procedures.

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