91,117 results

  • An investigation of cerebral asymmetry, echoic memory, and the stimulus suffix effect : a thesis ... for the degree of Master of Arts in Psychology at Massey University

    Blazina-Young, Elizabeth

    Thesis
    Massey University

    Echoic memory and hemispheric processing of two semantic categories of words were investigated utilizing a stimulus suffix paradigm under four delay conditions. The magnitude of the stimulus suffix effect was evaluated when combinations of concrete and abstract word lists and suffixes were monoaurally presented to the left and right ears. The results showed that the stimulus suffix effect occured for all information presented to both ears but was less pronounced when information was presented to the right ear. A right ear advantage for all information as well as a right ear advantage for abstract information was found. In addition, the right ear showed superior recall of abstract stimulus list and suffix combinations over other list and suffix combinations. Increasing delays between list and suffix presentation led to an increase in recall frequencies for terminal positions in the lists, but this increase was not systematic with delay. Results suggest that the right ear advantage often reported is due to right ear advantage for abstract information, and that echoic memory persists for at least 8 secs. These findings support the dual-trace processing model of hemispheric function and suggest that echoic memory may persist longer than the 2 secs implied by earlier researchers.

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  • Functional analysis of plant Mei2-like proteins : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Biochemistry at Massey University, Palmerston North, New Zealand

    Leung, Susanna Chui-Shan

    Thesis
    Massey University

    Molecular techniques were used to analyse the function of a novel class of RNA-bindmg proteins in plants, termed Mei2-like. The biochemical function of this class of proteins is unclear Although the conserved presence of three RNA recognition motifs (RRMs) in all members of the family suggests the importance of an RNA binding activity, the precise biochemical mechanism by which these proteins act is unknown. Genetic and molecular analyses of the founding member of the family. Schizosaccharomyces pombe Mei2p, provide of a conceptual framework for the studies of the plant Mei2-like proteins presented here. Therefore, the aims of this thesis were to 1) study the cellular localisation of Mei2p in plant cells, and 2) deduce the functions of plant Mei2-like genes by identifying the protein(s) that physically interact(s) with Mei2-like proteins. Transient expression of GFP-fused Mei2p in onion epidermal cells was performed to show that Mei2p localised into the nucleus in the presence of meiRNA, a non-coding mRNA. Thus plants seem to share the capacity with S. pombe for meiRNA-dependent nuclear localisation of Mei2p. Moreover, intracellular localisation of one of the plant Mei2-like proteins, TERMINAL EAR-Like 2 (TEL2), was studied in onion epidermal cells. The GFP-fused TEL2 localised into the nucleus without co-expression of any special RNA, suggesting that either some RNA species that assist nuclear localisation of TEL2 are already present in onion epidermal cells, or the mechanism of intracellular localisation of TEL2 is different from Mei2p. The yeast two-hybrid system was utilised to identify protein interactors with TEL2. Six proteins were identified, including the well-studied KORRIGAN (KOR) protein. Based on the proteins identified, speculation is offered on how these proteins interact with TEL2. Since TEL genes are expressed in the central zone (CZ) of meristems, and mitotic activity of cells in the CZ is low, TEL2 may be involved in controlling cell division in the CZ via interactions with these proteins.

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  • Growth and shear loss characteristics of an aerobic biofilm : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Technology in Biotechnology at Massey University

    See, Tiam Teng

    Thesis
    Massey University

    The application of biofilms in fermentation and waste treatment processes has been increasingly considered in recent years due to several inherent advantages over suspended growth systems. For example, they enable higher biomass hold-up providing larger quantity of cell per unit reactor volume which allows high loading rates. The biofilm systems, with fixed or immobilised cells, avoid washout conditions. The often difficult problems of sludge thickening, separation, recycle, and wasting associated with suspended growth systems are eliminated for biofilm systems. However, the major drawback lies in the control of film thickness in order to maintain high reactor productivities. The attached film thickness depends on both the biological parameters such as growth rate, and physical parameters such as hydrodynamic shear. The understanding of the growth and shear loss characteristics is a prerequisite for effective film thickness control. The main objective of this work therefore is to investigate the growth and shear loss characteristics of an aerobic biofilm utilizing phenol in a concentric cylindrical bioreactor. The growth and detachment of the biofilm was studied at different shear stresses, and their relationships were established. Detachment by shear was studied under two different conditions. One was examined simultaneously with growth under a constant shear stress where the biofilm detachment and growth occurred at the same time in the bioreactor. The other was examined via a separate shear test performed on the biofilm initially grown at a shear stress lower than that applied during the test. A method for measuring the torque exerted on the biofilm surface was first developed to enable computation of the related shear stress necessary for the study. The effect of film thickness on torque at film surface for a constant rotational speed was not significant. Shear stress can be conveniently determined from a quadratic relationship between torque and rotational speed for the range of film thickness studied. The substrate consumption is directly proportional to film thickness up to about 0.050 to 0.100 mm only, and beyond that it becomes independent of film thickness. The mass transfer resistance in the liquid phase appears to reach a minimum at shear stress greater than 3.44 N/m2 coinciding with the maximum steady-state substrate removal rate. The shear loss resistance of the biofilm increases with increasing shear stress during growth. The ultimate shear loss rate and shear stress relationship follows approximately: Rs = (40.82 – 2.750+0.1502 – 31.83e-0.610 ) × 10-2 The net growth rate varies with shear stress according to a parabolic function which predicts a shear stress of 19 N/m2 is required to achieve zero net growth. The biofilm-support adhesion must remain stronger than the film layer adhesion, otherwise, detachment will occur at the film-support interface rendering it impossible to control the film thickness.

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  • Fructan biosynthesis in Lolium perenne : tissue, cultivar and temperature effects on gene expression and protein accumulation profiles : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Biology at Massey University, Palmerston North, New Zealand

    Xue, Hong

    Thesis
    Massey University

    Cultivars of Lolium perenne with high concentrations of water soluble carbohydrates (WSCs) offer opportunities to mitigate greenhouse gas emissions (nitrous oxides) from grazed pastures and improve meat and milk production in livestock. Our previous studies demonstrated that fructan accumulation in the blades of high W SC grasses involves a strong gene x environment interaction. To identify the temperature effects on the expression of high sugar trait in the high sugar cultivars. we conducted a pot trial in climate chambers with temperature regimes set at10/10, 20/10 and 20/20°C (day/night), respectively. Water soluble carbohydrate concentrations, the expression of the key genes and proteins: l-SST (sucrose: sucrose l-fructosyltransferase), l-FFT (fructan: fructan l-fruclosyltransferase), 6G-FFT (fructan: fructan 6G-fructosyltransferase) and l-FEH l-fructan exohydrolases) involved in the fructan biosynthetic pathway of L. perenne were compared in blades and sheaths of three selected high sugar cultivars (P, A and H) and a common cultivar (F) grown under the three temperature regimes. We found that amongst the selected 3 high sugar cultivars, high molecular weight (HMW) WSC content was significantly higher in P and A cultivars, regardless of the temperature regimes. As expected, sheaths contained significantly higher concentrations of HMW WSCs (fructans) compared to leaf blades. The highest WSC contents in both leaf and sheath tissues accumulated at 10/10°C while the lowest accumulated at 20/20°C. Gene expression profiles demonstrated that all four genes studied were more significantly expressed in sheaths compared to blades, and the expression levels were highly correlated with fructan accumulation in this tissue. Low temperature resulted in significant up-regulation of l-SST in sheaths, but not in blades. l-FFT was highly expressed in blades of A and P cultivars. Unexpectedly. 6G-FFT was expressed more significantly in the control F cultivar. but not in the high sugar cultivar P. Protein expression profiles showed that l -SST protein accumulated to high levels in sheaths, whereas protein levels of l-FFT and l-FEH were higher in blades. l-SST protein levels in both blades and sheaths generally increased in plants grown at low temperatures, whereas l-FFT protein was not affected by low temperatures in blades and sheaths, furthermore, in both tissues there was no consistent effect observed between the different cultivars and temperature regimes on l-FEH protein levels.

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  • Explaining the cross-country variation in fiscal multipliers : a Bayesian approach : a thesis presented in partial fulfillment of the requirements for the degree of Master of Business Studies in Financial Economics at Massey University, Albany, New Zealand

    Purushothman, Nanda Kishora

    Thesis
    Massey University

    The effectiveness of fiscal policy is subject to crowding out. For nearly thirty years of annual economic data, we find that the crowding out of fiscal policy occurs through interest rate and exchange rate channels. The three most important determinants affecting the size and sign of fiscal multipliers during recessions worldwide are: (i) exchange rate regime, (ii) monetary policy, and (iii) current account balance. We find statistically significant results that these accompanying policies are the most influential sources of the cross-country variation in fiscal multipliers. Similarly, using an OECD dataset examining both economic expansions and recessions, we find that the three most statistically significant variables affecting fiscal multipliers in this case are: (i) exchange rate stance, (ii) private investment, and (iii) monetary policy. We find that the coefficient of the private investment variable is significantly negative, which is in line with the theoretical predictions. This finding is consistent with the hypothesis that expansionary government spending financed by debt crowds out private investment through rising interest rates.

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  • The effects of drying methods and storage conditions on pea seed (Pisum sativum L.) quality and the relationship between high temperature drying and maize seed (Zea mays L.) stress cracks : this thesis presented in fulfilment of the requirements for the degree of Master of Applied Science (Agricultural Engineering) in the Institute of Technology and Engineering, Massey University, New Zealand

    Thuy, Nguyen Xuan

    Thesis
    Massey University

    High temperature and high relative humidity adversely affect the quality of seeds, and are features of tropical climate. Seed drying and storage are being used increasingly in developing countries to improve seed storage and quality. This study was undertaken to evaluate a range of seed drying methods and storage conditions with the view to selecting an appropriate method(s) for use in tropical countries. Pea (Pisum sativum L.) seeds at three initial seed moisture content (m.c.) of 23.8, 18.0 and 14.5% were dried to 10% seed m.c. before storage. The performances of four different drying methods: artificial dryer (Kiwi Mini) set at 30°C or 45°C, natural sun drying, and in-bin natural ventilation drying were evaluated. Natural sun drying, and in-bin natural ventilation drying were conducted from March to May, 1997, when mean temperature and relative humidity during sunny days were 17°C and 60% respectively. The dried seeds were stored under two conditions: open storage at 20.5°0 and 55% relative humidity (r.h.), and closed storage at 25°C and 90% r.h. for 20, 40, and 60 days. Time and energy consumed for drying by the different methods were determined to compare the drying efficiency when combined with quality of the seed. Deterioration of the seed due to storage conditions and drying methods used was determined by assessing their effects on seed germination, abnormal seedlings, dead seed, hollow heart percentages, and conductivity. Seed samples dried by the Kiwi Mini dryer set at 45°C took 7 hours and those set at 30°C took 17 hours. It took 54 hours with natural in-bin ventilation drying, while sun drying took 37 hours. However, energy consumed when drying seeds at 30°C was 17 kWh, which was more than twice that at 45°C. Seed germination was not significantly different between drying methods, but averaged only 75% because of sprouting damage of the crop prior to harvest. Germinations after open and closed storage for 20 days did not differ, although some differences appeared after 40 days of storage. However, open and closed storage for 60 days significantly reduced seed germination to 54 and 33% respectively. Because seeds are heat-sensitive, drying air temperature and drying rate are particularly important to avoid internal seed breakage, cracking and splitting, fungal growth, and loss of germination and vigour. Selected studies have shown that seed can be dried at high temperature for a short time, followed by tempering to re-distribute moisture and temperature inside the seed, thus reducing the percentage of cracking. Thus, a second experiment was conducted with maize (Zea mays L) to study the impact on seed viability of high temperature drying followed by tempering. Maize at 28.5% initial seed m.c. was dried at 60°C for short periods of 5, 10, 15, 20, or 25 minutes, followed by tempering for 45 minutes at either 30°C or 21°C. This cycle was repeated until maize seeds were dried to 13.0% m.c.. The percentage of cracked seeds, germination immediately after drying, and after an accelerated ageing test, did not differ between 30°C and 21°C tempering. Drying exposure times of up to 10 minutes per cycle at 60°C caused vertical cracks in up to 50% of seeds, but seed germination remained over 90% and seed vigour was also maintained. The percentage of seeds with stress cracks due to high temperature drying (5 - 25 minute cycles) at 60°C followed by tempering had polynomial relationships with seed germination and vigour. Seeds dried at the same temperature without tempering had their germination reduced from 99 to 20%.

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  • A historical study of the search for oil in the Poverty Bay-East Coast district from 1874 to 1912 : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in History at Massey University

    Sharp, Ronald Murray

    Thesis
    Massey University

    This thesis deals with oil exploration in the Poverty Bay East Coast district between the years 1874 and 1912. The Geology of the district is outlined and a brief chronology of events is given. The achievements and problems of boring are related in Chapter I. Chapters III and IV unfold the story of exploration examining company promotion, share holding, public criticism and company expenditure. Chapter V gives brief biographies of most of the men of the district who promoted the companies. The occupations of the promoters are analysed. Public attitudes to the exploration are examined under three themes: the confidence that oil would be found, the question of local or foreign capital; and the benefits Poverty Bay would have received.[FROM INTRODUCTION]

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  • The exploitation of children as soldiers in the Philippines : an analysis of issues and challenges in social work practice : a thesis submitted in partial fulfillment of the requirements for the degree of Master of Social Work at Massey University, Albany, New Zealand

    De Ocampo, Ma. Irene Ordoña

    Thesis
    Massey University

    This study aims to explore and analyze how social workers directly working with child soldiers perceive the child soldier phenomenon in the Philippines. Specifically, it aims to come up with a picture of the child soldier phenomenon in the country, analyze the various factors or conditions contributory to the participation of children in armed conflict, explore the issues and challenges the child soldier phenomenon poses in social work practice and draw lessons or insights that can contribute to the improvement of current social work practice. This qualitative study used personal interview and instrumental case study methods in data gathering. Selected regional social workers of the government's welfare department, who have handled cases of children involved in armed conflict, served as the main source of information. They were selected through purposive sampling. Likewise, instrumental case study method was used to strengthen and enrich the data gathered using 31 selected case files of child soldiers. The information was analyzed using an ecological and structural framework. This research has shown that the child soldier phenomenon in the country is multidimensional and connected with various factors internal and external to the child. The existence of the phenomenon could not be attributed solely to a single factor but rather to combination of factors in the child's environment, which serve as a cumulative force that pushes the child to participate in the armed group. This study put forth the need for a multifaceted approach in social work practice with child soldier where all systems - micro, meso, exo, macro - in the child's immediate and distant environment are considered in the entire helping process. Likewise, it stressed the need for social work actions that provides not only immediate relief to individual child and her/his family, but also longer-term solutions that targets oppressive and unjust institutional and structural order in the society. It affirmed the importance of transformative social work practice where interventions go beyond mere palliative care and the importance of reflective practice where reflection-in-action is integral to the performance of social work profession.

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  • Gene expression in the precocious germination of late maturation Phaseolus vulgaris L. seeds: a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Plant Biology at Massey University

    Smith, Howard Russell

    Thesis
    Massey University

    Ethylene induces precocious germination in late maturation embryos (32-40 days after anthesis) of Phaseolus vulgaris L. cv. Seminole, thus overriding the endogenous controls which normally maintain quiescence. The possibility that ethylene exerts its effects at the gene expression level was investigated by in vitro translation of RNA extracted from embryo axis tissue of seeds induced to germinate precociously by incubation with ethylene. 35 S-labelled products so produced were analyzed by electrophoresis, fluorography, and scanning densitometry. Results were compared with normally germinating seeds and with embryos incubated in the absence of ethylene. Ethylene was found to induce a qualitative and quantitative change in gene expression in late maturation embryos detectable within 6 hours of ethylene exposure. Two products (37-38kD and 27kD) were up-regulated within 24 hours in both ethylene-induced precocious germination and normal germination. Four products (71kD, 67-68kD, 65-66kD, and 41-42kD) which appeared in normal germination were evidently not required for ethylene-induced precocious germination. In contrast with the findings of Misra & Bewley (1985;1986) for maize(Zea mays L.) no products could be identified as being unique to the developmental phase, however two products (38-39kD and 28kD) were strongly present in development but disappeared shortly after germination. A product of 22-23kD was apparently unique to the ethylene-induced precocious germination treatment and may represent a gene regulated by ethylene. This product was not seen until 24 hours after ethylene introduction. An attempt was made using SDS-PAGE to identify the major storage proteins of P.vulgaris to use as markers of the developmental phase, however this was only partially successful. Suggestions are made as to approaches and methods for future research.

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  • Improved mass cultivation of the marine diatom Chaetoceros calcitrans for shellfish hatcheries : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy in Biotechnology at Massey University, Palmerston North, New Zealand

    Tannock, Simon John Charles

    Thesis
    Massey University

    A medium for the optimal growth of Chaetoceros calcitrans in batch and continuous culture systems was developed. A method was developed for continuous culture of C. calcitrans that was free from detrimental infection by bacteria. The concentration of tested nutrients in the developed medium were sodium nitrate, 160 mg/L; sodium dihydrogen orthophosphate, 40 mg/L; and the molar Si:N ratio was 0.25 (99.9 mg/L sodium metasilicate). Isolated bacterial strains were shown to be detrimental to the growth of C. calcitrans in batch and continuous culture. Electrolytically treated water was suitable for the growth of C. calcitrans, but a subsequent flourish of bacterial growth at the late exponential phase reduced the quality of the algal cells and made the culture unsuitable for feeding to shellfish larvae. Heat treated water (95°C for ten and a half minutes) gave stable growth for the continuous culture of C. calcitrans in 38 L plastic bioreactor bags for at least 38 days. The superficial gas velocity in the culture bags was 0.09 L/min. Higher superficial gas velocities (e.g. 0.40 L/min were detrimental to C. calcitrans.

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  • Ground-level insolation in the UV-B spectral region : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Physics at Massey University

    Hartley, Bruce W

    Thesis
    Massey University

    This thesis describes the design and construction of two instruments for use in isolating the ultraviolet parts of the Solar spectral irradiance at Earth's surface. The first was a total UVA Pyranometer, which was undertaken to make preliminary investigations in the techniques of monitoring ultraviolet irradiances, as well as to provide useful data. The main part of this thesis was the construction of a portable, easily operated, interference filter spectrophotometer to isolate the ultraviolet-B spectrum into five discrete 10 nm passbands. However, as further reading will describe, realisation of only the two longer wavelength passbands was made due to deviations from the ideal quasi-rectangular passbands of the interference filter spectral transmittance curves. Discussion of how these problems can be overcome is presented in the conclusion. An outline on how the incident spectral solar irradiance could be found, from the five passbands, is presented along with some preliminary data from the two operational channels. An overall accuracy of 15% was obtained for data obtained, with better accuracies, to 7%, attainable by stabilisation of the instrument power supplies and, therefore, output voltage.

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  • Granulation of whole milk powder : a thesis presented in partial fulfilment of the requirements for the degree of Master of Engineering in Process Engineering at Massey University

    Field-Mitchell, Gary

    Thesis
    Massey University

    High-shear granulation is an attractive alternative to spray drying for producing dried milk products. The capital cost of a granulation circuit is likely to be much less than a spray drying circuit which will reduce the manufacturing costs of milk powders. This work investigated the high-shear granulation of milk powder using milk concentrate as a binding agent in order to determine the feasibility of granulation as an alternative to, or and improvement on, the spray drying process. This research has laid the groundwork for further investigation into milk granulation by defining the conditions for which granulation is achieved and describing the effects of processing parameters on granulation for a pilot-scale mixer granulator. The technical feasibility of granulation is shown by proving that granulation does not affect the quality of the milk. Designs for perceived continuous granulation circuits are included to aid in further milk granulation research. Successful granulation occurs at a total moisture content of approximately 11% (±1%). This was found to be suitable using either reconstituted or evaporated milk concentrated binder at between 20 and 50% total solids. The time of granulation affects the size distribution of the granules and the granule yield at the end of the process. A narrower size distribution with increasing granule sizes and a reduction in the granule yield is observed for longer granulation times. Granules were found to have better handling qualities than spray dried milk powders. Granules performed better in many functional tests having a higher bulk density, less change in bulk density during handling, better flowability and less fines. Granulation does not affect the chemical quality of the milk providing the granules are dried immediately after granulation. However, it was found that extended exposure of dried milk solids to a moisture content of 11% results in an unacceptable amount of insoluble material forming. Granules are well suited as a product for reconstitution but did not perform adequately in wettability tests, suggesting that their use as an instantised product would require further study and improvement. Further research is required to understand the role of lactose crystallisation and the generation of insoluble material to ensure scaling up of granulation will be successful. An investigation into continuous granulation would be useful for further milk granulation work.

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  • Further characterisation of the Dothistromin gene cluster of Dothistroma pini : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Biochemistry at Massey University, Palmerston North, New Zealand

    Teddy, Olivia Rachel

    Thesis
    Massey University

    The polyketide dothistromin is a toxin produced by the filamentous fungus Dothistroma pini that is thought to play a role in causing Dothistroma needle blight in Pinus radiata. Dothistromin is structurally similar to aflatoxin B1 (AF), a highly carcinogenic toxin with no known function that is produced by the fungus Aspergillus parasiticus and also to versicolorin, an intermediate of the well characterised biosynthetic pathways of AF and sterigmatocystin (ST). The structural similarities between AF/ST and dothistromin suggest that genes homologous to AF biosynthetic genes will be involved in dothistromin biosynthesis. AF/ST biosynthetic genes of A. parasiticus and A. nidulans are clustered and hence it is likely that the dothistromin biosynthetic genes are also clustered in a similar manner. Two λ clones, λKSA and λCGV1 containing portions of the putative dothistromin cluster have been isolated in previous studies. Another λ clone λCGV2 was also identified using an aflatoxin gene probe but it is unknown whether it is part of the dothistromin biosynthetic cluster. The λKSA clone contains part of a putative polyketide synthase pks dot (64% identical to A. parasiticus AF biosynthetic gene pksA). Two crucial domains required for functioning are contained within λKSA, the β-keto acyl synthase (KS) and acyl transferase (AT) domains. The putative pks dot is thought be involved in the beginning of the dothistromin biosynthetic pathway, working in a complex with a fatty acid synthase (FAS) to produce the intermediate noranthrone. A gene replacement construct was made using Multisite Gateway TM Recombination, replacing the AT and KS domains with an hph cassette. Disruption of the pks dot gene will confirm it's involvement in dothistromin biosynthesis and could also confirm the role of dothistromin in pathogenicity as if the putative polyketide synthase (pks dot ) is involved in the first step of the dothistromin pathway thus a knockout would form a mutant devoid of any intermediates. Confirming the involvement of pks dot would also provide evidence that like λCGV1, λKSA contains a portion of the dothistromin biosynthetic gene cluster. As the positioning of the three lambda clones λKSA, λCGV1 and λCGV2 relative to one another in the D. pini genome was unknown Southern blot analysis was implemented to identify any relationship between the three lambda clones. No evidence was found to suggest the close linkage of the three lambda clones however this does not discount any linkage at all. Southern blot analysis did provide evidence that ver-2 (77% identity to melanin biosynthetic gene phn1 of Cochliobolus heterostrophus) of λCGV2 is within dose proximity to a putative aflR gene (regulatory gene for activating gene transcription in AF/ST biosynthesis) suggesting a regulatory role of this putative aflR gene in melanin biosynthesis and not dothistromin biosynthesis. Further nucleotide sequencing of the λKSA clone revealed three putative dothistromin genes. Mox dot and ord dot have high amino acid identity to genes involved in the AF/ST pathways (70% identity to moxY and 51% identity to avfA of A. parasiticus respectively), suggesting similar roles in dothistromin biosynthesis. Epox dot showed high amino acid identity to an epoxide hydrolase of A. niger (hyll) suggesting it has a unique role in dothistromin biosynthesis as no homologs are seen in the AF/ST clusters. Southern blotting was also used to confirm the arrangements of genes from the λKSA clone within the D. pini genome. Further characterisation of genes involved in dothistromin biosynthesis will firstly enable understanding of the role of dothistromin in needle blight and secondly will enable further comparative studies between AF/ST and dothistromin.

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  • In situ recovery of secondary metabolites using adsorption resins : a thesis presented in partial fulfilment of the requirements for the degree of Master of Philosophy at Massey University, Palmerston North, New Zealand

    Ryan, Jason L. J

    Thesis
    Massey University

    Almost without exception a two to three fold increase in microbial secondary metabolite concentration was measured when adsorption resins were added in-situ during a submerged liquid fermentation. Anguidine was produced at a final concentration of 440 mg/L after five days in a shake flask that contained adsorption resin, compared to 300 mg/L without resin. Rapamcyin was produced at a final concentration of 87 mg/L after six days in a shake flask that had resin present, compared to 28 mg/L without resin. Ansamitocin P3 was produced at a final concentration of 24 mg/L after six days in a shake flask with resin, compared to 9.75 mg/L without resin. The increase in secondary metabolite concentration confirmed that the resins used provided a positive influence on secondary metabolite production. Adsorption resins for shake flask studies were selected based on their ability to achieve maximum adsorption of specific secondary metabolites in various fermentation systems. A library of adsorbed concentrations was collected for the three secondary metabolites studied. The lipophilicty of the metabolite, calculated by several software packages, was compared to the polarity of the adsorption resin to generate a relationship. By using the preceding set of data it is possible to select adsorption resins that improved the produced concentrations of the target organic secondary metabolites. The fermentation media compositions tested appeared to have no effect on the final product concentration when adsorption resins were added in situ during the fermentations. Based on the lipohilictiy of the secondary metabolite and the polarity of the resins, it is possible to select a resin that achieves a high adsorption concentration of the target organic secondary metabolite.

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  • Growth and flowering in Cyrtanthus elatus : a thesis presented in partial fulfilment of the requirements for the degree of Master of Horticultural Science at Massey University

    Dijkman, Dorothy A

    Thesis
    Massey University

    Cyrtanthus elatus (Hilliard and Burtt, 1986), commonly called Vallota, is a bulbous plant native to the Southeastern Cape province of South Africa, bearing an inflorescence with several large, bell-shaped, red flowers. The bulb and flower morphology, plus development of the inflorescence is described and was similar to Eucharis and Hippeastrum. Sympodial growth of leaves and inflorescences occurred from meristematic cells at the centre of the basal plate. A terminal inflorescence was initiated after 5-7 leaves. Large bulbs (7 cm diameter) had 5 leaves per growth unit and up to 5 inflorescence buds. Temperature and light intensity influenced growth and development of C. elatus. Inflorescences were initiated over a range of temperatures (13-29°C). Vernalization was not required. Floral initiation was optimal from 21-29°C and development to anthesis was optimal at 25°C. Quality of florets was best at 21°C which resulted in larger, brighter, orangey-red flowers. Rates of floral initiation were not affected by shading (50%), however, shading resulted in a high level of inflorescence bud abortion, particularly at warm temperatures (mean 23°C). Inflorescences did not emerge under 50% shade. Scapes were longest at 21-25°C, light intensity 722µMm-2s-1 . Inflorescence quality was maintained in a simulated home environment and past the macrobud stage, was independent of inflorescence development. Fluctuating warm temperature (17-26°C) and high light intensity (784µMm-2s-1 ) resulted in maximum root, shoot and offset growth. Good quality plants can be produced year-round under warm conditions (17-26°C), with two inflorescences per year from mature bulbs. Scheduling is complicated by the lack of a vernalization requirement. Shading is not recommended during production, Shipment in the dark at the macrobud stage is possible without deterioration. C. elatus is suitable as a patio and as an indoor pot plant.

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  • A heat shock process for the puffing of dried food gels : a thesis presented in partial fulfilment of the requirements for the degree of Master of Food Technology in Food Chemistry and Engineering at Massey University of Manawatu, Palmerston North, New Zealand

    Perreau, Rex George

    Thesis
    Massey University

    There has been increasing interest in recent years in the use of dehydration as a technique for the preservation of foodstuffs. An extract of production figures compiled by Van Arsdel (1963) is given in Table (l). The production per year, in tons, of six dehydrated foods in the United States of America is shown and indicates this trend which is particularly marked in the production of dried potatoes (mainly instant mashed potatoes), and non-fat milk solids.[FROM INTRODUCTION]

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  • The Indonesian House of Representatives : the behaviour and effectiveness : a thesis presented in partial fulfillment of the requirements for the degree of Master of Philosophy in Development Studies at Massey University

    Retnoastuti, Endah Tjahjani Dwirini

    Thesis
    Massey University

    There is a widespread opinion that the performance of the Indonesian House of Representatives, the Dewan Perwakilan Rakyat Indonesia, shortened as DPR, is weak. In other words, they have not been optimum In carrying out the legislative functions they are responsible for. In this thesis I critically assess the behaviour and effectiveness of the legislative institution, and in doing so, examine the Constitution and the Rules of Procedure to define the role and functions of DPR in the political system, breakdown the DPR structure to see its working process, and explore a bill deliberation. I conclude that DPR performances are inhibited by inadequate regulations and unconducive political systems. However, to some extent they have experienced considerable changes.

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  • Further studies of dothistromin toxin genes in the fungal forest pathogen Dothistroma septosporum : a thesis presented in partial fulfillment of the requirements for the degree of Master of Science in Biochemistry at Massey University, Palmerston North, New Zealand

    Feng, Feng, Zhilun

    Thesis
    Massey University

    The fungal pathogen Dothistroma septosporum is the main causal agent of Dothistroma (red-hand) needle blight, which is a devastating foliar disease of a wide range of pine species. Dothistromin is a difuranoanthraquinone toxin produced by D. septosporum and is considered as a possible virulence factor for the disease. Based on the similarity of chemical structure between dothistromin and aflatoxin (AF) /sterigmatocystin (ST) precursors, nine putative dothistromin biosynthetic genes have been identified, which are homologous to their corresponding genes in the AF/ST gene clusters. However, in contrast to all 25 AF biosynthetic genes tightly clustered in one region (70-Kb) of the genome, the dothistromin gene clusters are located on a 1.3-Mb chromosome and separated into three mini-clusters along with non-dothistromin genes. The dotC gene, located in the mini-cluster 1, is predicted to encode a major facilitator superfamily (MFS) membrane transporter involved in secretion of dothistromin. In this work, by constructing DotC-eGFP fusion protein containing mutants, the subcellular localization of the DotC protein was determined to be mainly targeted to the plasma membrane. The biological function of the dotC gene was characterized by targeted gene disruption. The dotC gene disrupted mutants showed a significant reduction of dothistromin production in both the medium and mycelium. In addition, the exponential growth of dotC null mutants was inhibited when exogenous dothistromin was presented and these mutants also displayed more sensitivity than the wild type strain to exogenous dothistromin. The results indicated that the DotC protein is a membrane associated protein and might have a role in dothistromin production and be involved in secretion of exogenously supplied dothistromin toxin. Two novel dothistromin biosynthetic genes, norA/B and verB (partial sequence), were identified by using degenerate PCR and D. septosporum genomic library screening. The putative NorA/B and VerB are postulated to encode a dehydrogenase and a desaturase, respectively and are similar to AF/ST genes. These findings further confirmed that the dothistromin shares biosynthetic pathway steps with AF/ST.

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  • Being @ : a thesis presented in partial fulfilment of the requirements for the degree of Master of Design at Massey University, Wellington, New Zealand

    Foster, Stuart

    Thesis
    Massey University

    Extra material images and video held with print copy in Library

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  • Granular approach to adaptivity in problem-based learning

    Hong, Sally

    Thesis
    Massey University

    Constructivist approach to learning has been around for quite some time. The constructivist theory has resulted in the development of a wide variety of learning environments, however the problem-based learning (PBL) environment is one of the most ideal and most popular area that implements the constructivism theory. PBL is an attractive approach to foster learner's critical problem solving and self-directed learning skills. However, it is difficult to implement effective PBL environments. A majority of existing PBL environments suffers from the fact that the students easily get inundated by the fine granularity of the problems and loose focus of overall aims of the learning process. This project has introduced student adaptivity technology into PBL environments to improve the effectiveness and efficiency of the learning process. To demonstrate the idea of PBL with student adaptivity, a web-based prototype is implemented in Process Costing, within the field of Accounting. Based on the architecture of the web-based intelligent educational systems, the problem base module is introduced. The basic architecture of the system is a typical three-tier, client-server structure. The client tier has the presentation interfaces that are implemented as HTML frames and run in a web browser. The application programs for performing adaptation, which were developed using PHP, reside in the middle layer, and communicate directly with the backend database: problem base, knowledge base that is the third tier. The web server as the communication channel also resides in the middle tier. With the system, students work on the real world costing calculation problems, and the system evaluates students' performance results on the problems to provide adaptation to the students. In summary, this project has successfully introduced the student adaptivity into the PBL environment. The strategies used in this thesis can be applied into the pure PBL educational systems to improve their adaptation capability.

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