Higher Degree Theses

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Organometallic chemistry of arsenic, phosphorus and other systems
(The University of Waikato, 1992) Arnold, Leslie John; Nicholson, Brian K.; Main, Lyndsay
Arsenic hydride and antimony hydride reactions with iron carbonyls were investigated and compared to analogous reactions using germanium hydrides. The reaction between arsane and Fe(CO)₅ is a new, higher yielding synthesis of [(μ₃-As)₂Fe₃(CO)₉]. The reaction between arsane and Fe₂(CO)₉ led to the new cluster [Fe₂(CO)₈(μ₄-As)]₂[Fe₂(CO)₆]. Characterisation was by an X-ray crystal structure determination. [Fe₂(CO)₈(μ₄-As)]₂[Fe₂(CO)₆] crystallises in the orthorhombic space group Pbca, with unit cell parameters a = 22.908(7), b = 17.521(9), c = 16.071(7) Å and Z = 8. This cluster consists of four AsFe₂ triangles linked by arsenic vertices and an iron-iron edge. In an attempt to prepare similar antimony clusters, stibane was reacted with Fe(CO)₅, Fe₂(CO)₉ and Fe₃(CO)₁₂, but no analogues were isolated. The β-ketophosphane (2-acetylphenyl)diphenylphosphane, Ph₂P[C₆H₄COMe], was prepared in a multi-step synthesis that involved; (i) coupling chlorodiphenylphosphane and 2-bromoethylbenzene, (ii) oxidation of the phosphorus with H₂O₂, (iii) oxidation of the ethyl group with CrO₃, and (iv) reduction at the phosphorus atom. Attempts to prepare the similar disubstituted phosphane PhP[C₆H₄COMe]₂, by an analogous route, instead afforded PhP[C₆H₄C(O)O]₂ at the CrO₃ oxidation step. The potential use of Ph₂P[C₆H₄COMe] as a ligand on metal centres was demonstrated by its electron-transfer catalysed reaction with Ru₃(CO)₁₂, which gave the expected product Ru₃(CO)₁₁[PPh₂(C₆H₄COMe)]. Gentle heating of Ru₃(CO)₁₁[PPh₂(C₆H₄COMe)] in heptane led to the cyclo-metallated cluster Ru₃(CO)₉(μ-PPh₂)(η²-C₆H₄COMe) through P-C bond cleavage. A single crystal X-ray diffraction study on Ru₃(CO)₉(μ-PPh₂)(η²-C₆H₄COMe) showed that it crystallises in the triclinic space group Pī with a = 10.200(11), b = 12.084(12) and c = 14.422(13) Å, a= 81.06(7), β = 77.18(8) and γ = 76.98(8)° and Z = 2. The cluster is derived from Ru₃(CO)₁₂ with three carbonyl ligands replaced by a μ-PPh₂ moiety and an η²-2-acetylphenyl group. The reactions between ortho-manganated acetophenone derivatives and various halides were investigated and compared to the analogous aryl-transfer reactions using mercury chloride. From the reaction between RC(O) C₆H₃R"Mn(CO)₄, ( R=Me, OMe, Ph; R"=H, OMe ), R'OH ( R'=Me, Et and Ph ) and CuCl₂ the following products were isolated [Figures x 4] These can be explained in terms of competition between Mn-Cₐᵣᵧₗ bond cleavage ( the first two products ), or in terms of CO insertion into the Mn-Cₐᵣᵧₗ bond, with subsequent attack by the solvent ( the last two products). The reaction between 2-MeC(O) C₆H₄Mn(CO)₄, and PPh₂Cl involves CO replacement to give fac-[2-MeC(O)C₆H₄Mn(CO)₃(PPh₂Cl)] in essentially quantitative yield. Prolonged refluxing of fac-[2-MeC(O)C₆H₄Mn(CO)₃(PPh₂Cl)] yields Mn₂(μ-η¹-η¹-PhPPPh)-(μ-Cl)₂(CO)₆ in which the newly formed diphosphane ligand bridges two non-bonded manganese atoms; this compound was characterised by an X-ray structure analysis; Pī with a = 10.980(4), b = 11.756(3) and c = 12.186(3) Å, α = 96.20(2), β = 99.51(2) and γ = 96.56(2)° and Z = 2. The probable products from the reaction between SnCl₂ and 2-RC(O)C₆H₄HgCl ( R = Ph, Me) and from the reaction between RₙSnCl₄₋ₙ and 2-MeC(O)C₆H₄HgX ( R = Buⁿ, n = 1, X = Cl; R = Ph, n = 2, X = I) are the acylaryltin derivatives 2-RC(O)C₆H₄SnX₂Cl ( R = Ph, X = Cl; R = Me, X = Cl, Ph) and [2-MeC(O)C₆H₄]₂Sn(Buⁿ)Cl shown below [Figures x 2] These assignments were based on ¹¹⁹Sn and ¹³C nmr spectroscopy.
A parallel lisp and multivariate polynomial GCD implementation
(The University of Waikato, 1991) Willcock, Diane K.; Broughan, Kevin A.
This thesis is concerned with the intersection of two fields of study - computer algebra and parallel processing. The operation of multivariate polynomial greatest common divisor (gcd), an important and fundamental computer algebra operation, is investigated for amenability to parallelisation following the investigation of a suitable environment for implementation of a parallel computer algebra algorithm. After researching the requirements of a parallel computer algebra system, these were matched as closely as possible to available hardware. The choice of an array of transputers as the hardware system lead to the development of a parallel lisp for such a system as there was none readily available. The result was a useful, experimental, coarse-grained, message-passing parallel lisp (Tlisp) based on the eval-server model where each processor in the array (configured in a tree) executes its own lisp process, reading, evaluating and printing s-expressions independently of the others, but with facilities for passing s-expressions to and from its neighbours. Following an appraisal of algorithms available for calculating multivariate polynomial gcds, Zippel’s sparse modular gcd algorithm was selected as the most suitable candidate for parallelisation and implementation in Tlisp. Evaluation of the performance of both Tlisp and the parallel gcd algorithm was achieved by detailed examination of how they performed during execution for a range of test data. The results of the performance experiments and the practical experience gained from a working parallel lisp system and its implementation of an important computer algebra algorithm clearly show that there is much potential for a medium- to coarse-grained message-passing parallel system in the quest for a suitable system for parallel computer algebra.
Transition metal carbonyl clusters incorporating silicon
(The University of Waikato, 1991) Van Tiel, Martin L.; Mackay, Kenneth M.; Nicholson, Brian K.
This thesis reports the reactions of silicon hydrides with the following metal carbonyls; Fe(CO)₅, Fe₂(CO)₉, Co₂(CO)₈ and Co₄(CO)₁₂. The silicon hydrides investigated include SiH₄, Si₂H₆, PhSiH₃, BrSiH₃, ISiH₃, H₃SiOSiH₃ and H₃SiSSiH₃. The reaction of Si₂H₆ with Co₂(CO)₈ at low reactant ratios (1 : 2.5) gave the cluster H₂Si₃Co₆(CO)₂₀ (3.7). This is a rare example of a silicon-transition metal cluster with Si-H bonds. The structure can be regarded as Si[Co₂(CO)₆(μ-CO)]₂ with both bridging carbonyls replaced by μ-Si(H)Co(CO)₄ groups. Further infrared evidence for the previously postulated cluster Si₂Co₆(CO)₂₀ was also obtained. [Figure 3.7] In attempts to crystallise an unknown product from the reaction of SiH₄ with Fe(CO)₅ and Co₂(CO)₈ using THF, ionic products were formed. [FeCo₃(CO)₁₂]⁻ was isolated with [Fe(THF)₄(H₂O)₂]²⁺ as the counter ion. The structure adopted by [FeCo₃(CO)₁₂]⁻ is very similar to that found for the neutral carbonyl, (Co₄CO)₁₂. [Cp(CO)₂FeGe]₂Fe₃(CO)₉ (3.19) was prepared for NMR and crystallographic studies for comparison with the previously reported silicon and tin analogues. The reaction of PhSiH₃ with Co₄(CO)₁₂ resulted in the formation of the square-bipyramidal cluster (PhSi)₂Co₄(CO)₁₁ (4.6) in high yield. This is compared with the wide range of known (RP)₂M₄Lₓ (R = phenyl or p-tolyl) clusters. [Figure 3.19] [Figure 4.6] Initial investigation of BrSiH₃ with Co₄(CO)₁₂ tentatively identified a similar cluster (BrSi)₂Co₄CO)₁₁, which retains a functional halogen group. The reaction of BrSiH₃ or ISiH₃ with Co₂(CO)₈ shows evidence for the formation of the orange clusters (CO)₄CoXSiCo₂(CO)₇ (X = Br, I). These clusters also retain the halogen group via which further substitution could occur. The reaction of H₃SiOSiH₃ with Co₂(CO)₈ proved to be very unpredictable. Tentatively identified products include two clusters which retain the Si-O-Si linkage, O{[Si[Co(CO)₄]Co₂(CO)₇}₂ and O[SiCo₃(CO)₉]₂. Reaction of the sulphur analogue H₃SiSSiH₃ with Co₂(CO)₈ forms the unique cluster SSi₂Co₄(CO)₁₄ (5.9). This cluster consists of a Co₂(CO)₆ unit doubly bridged by SiCo(CO)₄ groups. Both silicon atoms are further linked together with a sulphur atom giving rise to a very acute Si-S-Si angle of 70.3(1)°. The reaction of the analogous hydride H₃GeSGeH₃, with Co₂(CO)₈ shows no formation of a similar product. At higher temperatures the reaction of H₃SiSSiH₃ with Co₂(CO)₈ forms the previously reported cluster S₂Co₄(CO)₁₀ (5.16) which consists of a rectangular cobalt plane with sulphur atoms quadruply bridging both faces. An accurate structural determination of this cluster allows for a detailed discussion. [Figure 5.9] [Figure 5.16] The reactions of various silicon chlorides (SiCl₄, Si₂Cl₆ and Cl₃SiOSiCl₃) with [Co(CO)₄]⁻ were investigated. With SiCl₄, initial formation of the siloxy cluster Cl₃Si-O-CCo₃(CO)₉ was observed and further substitution resulted in the formation of (CO)₄Co(Cl)₂SiOCCo₃(CO)₉ (6.4, characterised crystallographically). In attempts to further substitute the remaining chlorine atoms the carbido cluster [Co₆C(CO)₁₅]²⁻ (6.9) was formed and the structure of the [Et₄N]⁺ salt was determined. [Figure 6.9] [Figure 6.4]
Life history strategies of New Zealand Ceriodaphnia (Crustacea: Cladocera): a comparative study
(The University of Waikato, 1993) Greenwood, Tracey; Green, John D.; Chapman, M. Ann
The seasonal changes in the plankton communities, and the dynamics and life histories of the Cladocera of Lake Mangakaware, were studied over a period of 19 months, during which time populations were sampled at weekly or two weekly intervals. Lake Mangakaware, a small, polymictic lake in the North Island of New Zealand, is characterised by a high nutrient status, low Secchi transparencies, and an unstable thermal regime. In the algal community, small euchlorophycean genera and diatoms predominated. Peak abundances occurred in autumn and late spring and were due almost exclusively to Tetrastrum triangulare and Aulacosira distans respectively. The frequent mixing events precluded the prolonged abundance of any one species and species replacements were rapid. Small species (< 30 μm) predominated amongst the dominant class (Euchlorophyceae), but there were frequent occurrences of large, unpalatable and/or nutritionally poor genera (Aulacosira, Closterium, Trachelomonas). Amongst the zooplankton, the Copepoda and Rotifera predominated. The rotifer community exhibited a pattern of sharp sequential peaks in the abundance of different species. Maximum density occurred in summer (1989) due almost entirely to Keratella cochlearis. The Copepoda were generally low in abundance in winter, but increased in summer and autumn periods. The four cladoceran species: Bosmina meridionalis; Ceriodaphnia pulchella; C. dubia; and B. longirostris; exhibited disjunct population maxima, with peak abundances occurring in mid summer (1987), autumn (1988), spring (1988), and summer (1989). Only B. longirostris was perennially present. The Cladocera of Lake Mangakaware have life histories which predispose them to success at particular times of the year. All species exhibited low fecundities and lipid scores, indicating that resource availability was low and competitive interactions and starvation resistance were probably important in determining species success. Increases in body size in cooler seasons were correlated with higher egg volumes, but not with higher clutch sizes, giving further support for the view that available food was limited. B. longirostris appears to be the most successful planktonic cladoceran in Lake Mangakaware. It is a small species, but produces relatively large neonates which mature quickly. It appears able to maintain populations for prolonged periods with low fecundity, produces ephippia as a means of persistence, and is not particularly vulnerable to predation from Mesocyclops leuckarti. Its selective feeding mode is probably favoured in Lake Mangakaware, where palatable algal species are in low density or difficult to obtain. B. meridionalis is a less able competitor than its congener and is apparently disadvantaged by long development times at low temperatures. The seasonal success of each of the two species of Ceriodaphnia appears to be partly determined by temperature. C. pulchella was the more abundant species but was restricted to warmer seasons and, like B. meridionalis, has a prolonged development time at low temperature. In contrast C. dubia grows quickly at low temperature. The life history responses of C. pulchella and C. dubia to different food and temperature regimes were examined using two way ANOVA for the treatments: 23°C-high food; 23°C-low food; 13°C-high food; 13°C-low food. Growth, fecundity, and resource allocation were examined and the two species found to be different in critical aspects of their life history. At high resource levels, C. dubia had a higher fecundity than C. pulchella and increased its reproductive effort with age while maintaining a high growth rate. However, at low food levels, C. dubia lost most of this advantage and development times were also considerably prolonged. C. dubia neonates were larger than those of C. pulchella, yet possessed the same amount of lipid for any given regime. C. pulchella, although the smaller of the two species, with generally lower fecundity and longer development times, produced relatively larger neonates than C. dubia. C. pulchella was less responsive to low food level, curtailed growth after maturity, and maintained a rather constant clutch size regardless of food availability. Offspring were quite resistant to starvation and were able to reproduce without provided food, regardless of maternal history. The results suggest that subtle differences in life history can determine seasonal success and competitive outcome between similar species. Very large differences in life history strategy or selection pressure need not be invoked.
Glutamate dehydrogenase from the extremely thermophilic archaebacterial isolate AN1
(The University of Waikato, 1993) Hudson, R.C.; Daniel, Roy M.; Ruttersmith, L.D.
An NADP-specific glutamate dehydrogenase (E.C. 1.4.1.4) constituted approximately 10% of the soluble cell protein of the extremely thermophilic archaebacterial isolate AN1. This enzyme was purified to homogeneity in high yield, using column chromatography on Reactive Red-Sepharose CL-6B and hydroxyapatite. The glutamate dehydrogenase was a tetramer of Mr 204 000. It was highly thermostable with half-life values of 12.5 h and 47 min at 90°C and 103°C, respectively. The pI was 4.0 and the pH optimum was 8.25 for both oxidative deamination and reductive amination reactions. Activity in the oxidative deamination direction was markedly enhanced by calcium, magnesium and manganese ions. Glutamate synthase activity was about 50% of the glutamate dehydrogenase activity. The thermostability and pH optimum of the glutamate synthase activity was the same as for the glutamate dehydrogenase activity. Apparent Km determinations at 40, 60, and 80°C revealed increases in apparent Km’s with increasing temperature. The kinetic mechanism of the forward and reverse reactions of the glutamate dehydrogenase was investigated using initial velocity studies and inhibition studies with products and substrate analogues. Many of the product inhibitions were of a nonlinear (parabolic) nature. The results of the experiments were consistent with a steady state random mechanism but not with an ordered mechanism or a rapid-equilibrium random mechanism. The results also indicated that there was a preference for the cofactors to bind the enzyme first (both reaction directions), and for 2-ketoglutarate to bind the enzyme second (reductive amination reaction). The true Km values (mM) for NADP⁺, glutamate, NADPH, 2-ketoglutarate and ammonia were 0.086, 2.0, 0.015, 0.71 and 10.7, respectively. The true Kᵢ (dissociation constant) values (mM) were 0.054, 1.27, 0.018, 1.79 and 8.03 for NADP⁺, glutamate, NADPH, 2-ketoglutarate and ammonia, respectively.
Treatment of agricultural wastewaters and growth of Schoenoplectus validus in constructed wetlands
(The University of Waikato, 1994) Tanner, Chris C.; Thompson, Keith
Constructed wetlands have the potential to provide simple, low-cost, low-maintenance, natural treatment systems for agricultural wastewaters. The aims of the present study were: 1. To evaluate the treatment performance of gravel-bed wetland systems supplied with dairy farm wastewaters and provide basic data for the development of suitable loading criteria. 2. To investigate the effect of wetland plants on treatment performance. 3. To investigate the effect of wastewater loading rates on plant productivity, nutrient uptake, and growth characteristics. Schoenoplectus validus (soft-stem bulrush) was chosen as the test species, since this is the plant most commonly used in wetland treatment systems in New Zealand, and is also in widespread use in the United States and Australia. The effect of loading rate and presence of plants on wastewater treatment was investigated over a 20 month period, in four pairs of gravel-bed wetlands operated with different loading rates of dairy shed wastewaters. Mean annual suspended solids (SS) removals of 75-85% were achieved in the wetlands, irrespective of loading rate or the presence of plants. In the planted wetlands, mean mass removal of carbonaceous biochemical oxygen demand (CBOD), during the first 12 months of monitoring, increased from 76 to 90%, total BOD (CBOD + nitrogenous BOD) from 50 to 80%, faecal coliforms from 95 to over 99%, total nitrogen (TN) from 48 to 75%, and total phosphorus (TP) from 37 to 74% as wetland retention time rose from 2 to 7 days (i.e. inversely related to loading rate). The unplanted wetlands generally showed similar performance to the planted wetlands at low loading rates, but poorer BOD, nitrogen and phosphorus removal at the highest loadings tested. Comparison of the performance of the horizontal-flow wetlands with that of up-flow wetland tanks, showed similar reduction of BOD and SS in relation to volumetric loading, but reduced N and P removal, particularly at high loading rates. Net annual plant production measured in the wetlands was high, rising from ~2.5 to 3.5 kg (dry weight) m⁻² with increasing wastewater loading, during the first growth season. Plant biomass and tissue nutrient levels declined down the wetland channels reflecting fertility gradients in the wetlands. Nutrient accumulation in living and dead plant biomass in mid-summer, after two years of wetland operation, although high compared to levels reported for natural communities, only represented 6 to 10% of the N removal and 6 to 13% of the P removal recorded for the wetlands. Above-ground litter inputs from plants were estimated to contribute significant quantities of readily and slowly available carbon substrates to the wetland surface, equivalent to between 60 and 125% of the available organic carbon loadings, and 80 to 190% of the CBOD loadings supplied to the wetlands in wastewaters. In further experiments, above and below-ground plant growth was compared in wetland microcosms batch-fed with a range of agricultural wastewater types and strengths, with and without nutrient additions, and in complete nutrient solutions. S. validus was capable of growth over a wide range of wastewater nutrient levels, but showed maximum growth at the highest levels tested. Reduced rooting depths were however noted in the higher strength organic wastewaters. Comparisons with root development in nutrient solutions and nutrient ammended wastewaters suggested that factors associated with organic compounds in the wastewaters (e.g. hypoxic stress caused by high BOD levels), rather than increasing nutrient levels, restricted root penetration. Similar reductions in the proportion of deep-growing roots were noted at high loadings in the larger-scale wetlands. These growth responses have important consequences for the design of subsurface-flow wetland systems, where bed depths are matched to plant rooting depth, to maximise contact between wastewaters and the root-zone.
Re-membering the witch and the goddess: feminist ritual-makers in New Zealand
(The University of Waikato, 1993) Rountree, Kathryn; Day, Patrick; Macdonald, Judith
In the mythologies of Western societies, the witch and the goddess constitute polarized images of female power, power which is both beyond the domain of male control and designated illegitimate (in the case of the goddess) or undesirable (in the case of the witch) for ordinary women. This thesis is a product of research amongst women in New Zealand who, by claiming that the witch is a diabolized version of one aspect of the goddess, challenge the dichotomization of these two images. The women belong to a movement called alternatively “feminist witchcraft” or “Goddess spirituality” which was begun by feminist activists in the United States during the late 1960s, grew and spread in the twenty five or so years since, and today forms a sub-group within feminism in a number of Western countries. The women with whom I worked self-identify both as “witch” and “goddess”. In their everyday lives, and especially through their ritual practices, they aim to discover, embody and explore the power which the symbols “witch” and “goddess” represent. I argue that women’s self-identification in these ways is aimed at collapsing the dualistic symbolic system which polarizes the witch and the goddess as images of womanhood. I see such self-identification as a symbolic act of self-empowerment through which women begin to see and experience themselves as strong and autonomous. By re-membering the witch and the goddess, women re-member parts of themselves to which they have been denied legitimate access under patriarchy. The thesis is based on three years’ anthropological fieldwork amongst feminist witches in Auckland, where the movement is strongest, and Hamilton, where I lived over the period. I also had some limited contact with witches in Christchurch. As background to the ethnography, I trace the movement’s origins, development and connections in the United States and New Zealand. I compare expressions of the movement in New Zealand, the United States and England, focussing on the special character of the movement in New Zealand. The ethnography is primarily an examination of the attraction of witchcraft for the women with whom I worked, their world views, and their ritual practices. I emphasize the subjective meanings which witches give to their beliefs, values and practices. I conclude that the movement is a phenomenon constructed deliberately out of a variety of ancient and contemporary elements by women determined to bring a spiritual dimension to feminism. I see feminist witchcraft/Goddess spirituality as one expression of a much broader contemporary movement, what witches call a “new consciousness”, which emerged out of the 1960s counter-culture. This broader movement, whose various expressions include, along with feminism, the ecology movement, civil rights and gay rights movements, the anti-nuclear movement and holistic healing movements, challenges social and political institutions founded on dominance and oppression: the emphasis is on partnership in social relations, care for the planet, and a holistic world view. For witches, the symbol of holism, balance and connection is the Goddess.
Receptors for growth hormone and insulin-like growth factors in cartilage using antler as a model for bone growth
(The University of Waikato, 1994) Elliott, Jennifer Lynn; Molan, Peter C.
Bone growth in young mammals is a major determinant of eventual individual size, and ongoing bone metabolism is necessary to maintain a mineral balance for essential physiological processes. GH, IGF-I and IGF-II stimulate growth in many tissues and are implicated in cartilage and bone growth. Tissue sensitivity to a hormone may be gauged by receptor levels and the main objective of this thesis was to examine and characterise the receptors for GH and the IGFs in tissues of developing bone. Antler was used as a model for bone growth because it is similar in histochemistry to somatic long bones. It may be removed humanely, undergoes regeneration and grows rapidly, making it a useful tissue for research in growth. Receptor localization in tissues of the growing antler tip was determined using autoradiographical studies and the receptors were characterised using competitive binding assays and affinity cross-linking studies. Production of IGFBPs was assessed and analysed for interference of hormonal binding to receptors. Ontogeny of receptor distribution patterns over the antler growth phase was also studied to assess changes in localization, or implied function, occurring with tissue maturation. Administration of testosterone to deer bucks during the antler growth phase to induce precocious tissue maturation was used as a tool to assess the direct effects of circulating androgens on cartilage development, and changes to receptor localization relative to this treatment. No GH receptors were detected in antler tissues. IGF-I and IGF-II bound to receptors that had characteristics of type 1 and type 2 IGF receptors, respectively. Highest levels of IGF-I binding were in the maturation zone and IGF-II binding in the proliferative zone. IGFBPs were produced in higher levels in pre-cartilage than in cartilage tissues. Ontogenetic changes in IGF-I binding were observed by changes in distribution patterns at a late stage of antler growth. Distribution patterns of IGF-II binding did not change over the growth phase. Enhancement of antler mineralization and ossification was achieved to a limited degree by testosterone administration, suggesting that testosterone might not be as potent a stimulator of antler tissue maturation as its metabolites. In conclusion, antler growth is independent of direct stimulation by GH. IGF-I and IGF-II each preferentially bind to distinct receptor populations in antler tissues, with different tissue distribution, hormonal specificity and ontogeneticity. Localization of IGF receptors in antler tissues implied a role for IGF-I in matrixogenesis and a role for IGF-II in cell proliferation. IGFBPs were implicated in the regulation of IGF-II actions in vivo. This evidence suggests that antler tissue provides a unique opportunity to study the endocrine effects of IGFs on cartilage and bone.
A challenge to the current concept of genre: writing up research
(The University of Waikato, 1993) Paltridge, Brian Richard; Crombie, Winifred
The study described in this thesis represents an attempt to develop a framework for genre analysis which reflects what it is that leads users of language to recognise communicative events as instances of particular genres. It does this by both testing and extending a definition of genre provided by John Swales which, to date, is unbacked by research evidence or investigation. This definition holds that genres are instanced by communicative events with shared sets of communicative purposes which, even though they may vary in their prototypicality, are constrained by various conventions as to what is allowable in terms of content, positioning and form. The texts which form the basis for the study are drawn from the area of written ‘research reporting English’; that is, the writing up and publication of the results of experimental research in English. Both social-semiotic and socio-psychological frameworks provide an initial basis for the examination of a collection of ‘typical’ instances of the specific genre (research reporting). The results of this examination then provide a basis for the presentation of a proposed genre analysis framework which synthesises a range of approaches and methods. The principal initial theoretical frameworks chosen for the study are systemic functional linguistics, a social-semiotic view of language originally formulated by M.A.K. Halliday, based largely on the work of Bronislaw Malinowski and J. R. Firth and frame semantics, a sociopsychological view of language proposed by Charles Fillmore and based on the work of Del Hymes, Eleanor Rosch and others working in the fields of cognitive science and artificial intelligence. Although the first of these frameworks is shown to have certain strengths, it is also revealed to have certain limitations. The second of these frameworks is then proposed as the most comprehensive and adequate for explaining the assignment of communicative events as instances of particular genres. A framework for genre analysis is then presented which draws on work in the areas of discourse analysis, pragmatics, language and cognition, natural language processing, artificial intelligence and critical theory and practice. The framework aims to reflect research on the interaction between meaning-creation and perception and arrangement, storage and retrieval in the context of the perception and production of specific communicative events as instances of particular genres. It also aims to establish a framework which allows us to account for the fact that certain instances of genres are further from what may be described as the genre prototype than others and for the fact that relationships are perceived between instances which may be structurally very different. Within the context of the texts examined, the study, in general terms, validates Swales’ definition of genre. In contrast to the position held by Swales, however, the study concludes that while it is possible to make statements concerning meaning-creation and goal-direction within the context of genre, it is a matter of much greater complexity to draw conclusions regarding the relationship between genre and the actual language of texts. The final chapter attempts to re-define the term ‘genre’ in the context of the research findings.
A critical examination of the effectiveness of Te Tiriti o Waitangi and Treaty of Waitangi training programmes in health services
(The University of Waikato, 2026) Edmonds, Moengaroa; Waitoki, Waikaremoana; Tan, Kyle K. H.
The overall aim of this study was to critically examine the effectiveness of te Tiriti o Waitangi and Treaty of Waitangi based training in the publicly funded health system in Aotearoa as a tool for addressing health inequities, and to contribute to the broader Kaupapa of improving Māori health through systems that honour te Tiriti partnership. The research was conducted during a period of significant restructuring of the health system, a result of reforms that were framed as opportunities to strengthen Māori voices in health decision-making and to uphold te Tiriti o Waitangi obligations. However, the reforms and subsequent amendments have also been marked by contestation over the place of tino rangatiratanga and the privileging of Treaty principles over the text of te Tiriti. This study set out to examine the role of Tiriti o Waitangi training within the publicly funded health system, exploring how training currently, or could, more effectively respond to legislative change, address inequities, and position health professionals and organisations in relation to their Tiriti responsibilities. Three training programmes were examined; an online e-Learning module, a kanohi-ki-te-kanohi cultural awareness workshop that included Tiriti o Waitangi and Treaty of Waitangi learning, and a Critical Tiriti Analysis workshop delivered as part of a wider scaffolded training programme by a Public Health and Rautaki team at Te Whatu Ora, Waikato. A mixed-method approach was selected to capture learning across groups. The research framework for this study integrated Kaupapa Māori philosophy, te Tiriti o Waitangi and Critical Tiriti Analysis to guide the research. In Chapter 4, post training surveys of the e-Learning module were analysed covering two separate periods – between July 2021 and August 2023. This is followed by an analysis of post training surveys over four different periods between May 2021 to March 2023. Interviews were conducted with 15 participants made up of staff in training at Te Whatu Ora and training providers of the two kanohi-ki-te-kanohi programmes. The use of multiple data sources enabled methodological triangulation and strengthened the credibility of findings. The study makes a significant contribution to scholarship on Tiriti training, Kaupapa Māori research, and evaluation in public health. It demonstrates that while training is a necessary process in addressing inequities, it is insufficient for transformation to occur. Enduring progress toward health equity for Māori requires systems that honour te Tiriti, not only in learning spaces, but in governance, policy, and everyday institutional practice.
Low molecular weight cationic and anionic peptides from macromolecular aggregates in bovine seminal plasma and their effects on bull sperm
(The University of Waikato, 1994) Al-Somai, Niaz Mohamed Rashed; Molan, Peter C.
The detrimental effect of bovine seminal plasma on sperm is believed to be the action of its constituent proteins and peptides. The major proteins in seminal plasma are known to be aggregates of peptides of low molecular weight. Various researchers have reported that the anti-sperm activity in seminal plasma is spread over a wide range of molecular weights. High molecular weight cationic material from seminal plasma is believed to be more damaging to sperm than high molecular weight anionic material. The substance or substances responsible for the detrimental effect have not been fully characterised. The current study was undertaken to examine, more thoroughly, the detrimental effect of bovine seminal plasma on sperm, to isolate and characterise the component( s) of low molecular weight from the aggregate, and to study the interaction between these components with regard to the formation of aggregates and their effect on sperm motility. In order to achieve this goal, a method had to be developed to isolate the anti-sperm component(s), to give a better dissociation of the component(s) from the macromolecules and to disaggregate the macromolecules to their constituents. Preliminary investigation, using gel permeation chromatography, indicated that low molecular weight fractions from bovine seminal plasma were more detrimental to sperm motility than those of higher molecular weight. By dialysis in the presence of citrate or under acidic conditions followed by gel permeation chromatography under acidic conditions, the low molecular weight components were released from the aggregates and they were assessed for their detrimental effects on sperm. Although they were found to have more detrimental effect than the parent aggregate, they tended to reaggregate to higher molecular weights under neutral conditions. Methods evaluated as ways of achieving disaggregation were: dialysis in membranes with cut-off of various molecular weights; gel permeation chromatography under dissociating conditions; selective precipitation with isopropanol; immobilisation of the cationic proteins on a cation exchanger, with extensive washing with acetonitrile at pH 3 to dissociate the anionic component(s), then elution with 0.01 mol/l NaOH; separation of the hydrophobic from the hydrophilic component(s) by immobilisation on a hydrophobic interaction column (Phenyl Superose); and reverse phase chromatography on FPLC columns to separate proteins and peptides. Further sequential use of these methods on FPLC columns for final purification resulted in the isolation of the anionic and cationic peptides in a reasonably homogenous form. All the fractions obtained using the above methods were assessed for their effects on sperm washed by centrifugation in Ficoll solution to free them from seminal plasma. The washed sperm were suspended in a defined diluent to provide a good test system for examining the effects of seminal plasma and its fraction on sperm. From attempts to isolate the damaging component from seminal plasma, it appeared that relatively high molecular weight cationic or anionic proteins retained anti-sperm activity while they were in aggregated form, however, the extent of activity depended on the form of aggregation. The isolated cationic peptide was highly basic in nature, highly active against sperm and failed to form an aggregate by itself under neutral pH. The isolated anionic peptide was hydrophobic in nature, inactive on sperm and failed to form an aggregate by itself. A combination of the active cationic and the inactive anionic peptide succeeded, in a certain ratio, in the formation of a large aggregate at neutral pH. This was demonstrated by a reaggregation study with radiolabelled anionic peptide which showed incorporation in aggregates which eluted at the high molecular weight region indicating that the two peptides were required for formation of aggregates. The combination of the two peptides reduced the detrimental effect of the active cationic peptide. It is hypothesised that the aggregates in seminal plasma are an assembly of the active cationic peptide with the inactive anionic peptide. This aggregation is a way of attenuating the damaging effect while the release of these low molecular weight from the large aggregates accentuates the damaging effects. The well established antibacterial activity in seminal plasma is highest in the form of high molecular weight aggregates. Aggregation in the form of high molecular weight components may serve to protect the male reproductive tract against bacterial invasion and protect the sperm from the toxic effect of the low molecular weight components by being in the form of high molecular weight aggregates.
A study of diversity in anaerobic cellulolytic thermophilic bacteria
(The University of Waikato, 1992) Rainey, F.A.; Morgan, Hugh W.; Janssen, Peter H.
Enrichments were set up using anaerobic bicarbonate buffered medium with cellulose and various other polysaccharides as the enrichment substrate. The inocula were water and sediment samples from freshwater and brackish thermal springs. These enrichments yielded anaerobic, cellulolytic, thermophilic bacteria with three distinct morphologies. Two of these isolates, a spirochete and a Thermotoga-like organism, were easily distinguished on the basis of their characteristic morphologies. The remaining isolates were rod-shaped and not easily distinguishable. The spirochete and the Thermotoga-like organism were fully characterised and their taxonomic position determined. The majority of the rod-shaped isolates had temperature optima of 70°C, in contrast to the previously described cellulolytic, thermophilic species of the genus Clostridium, which have temperature optima of 60-65°C. The degree of diversity within this group of rod-shaped bacteria and previously described isolates from various geographic locations was determined using three methods, numerical taxonomy, protein electrophoresis and phylogenetic analysis of the 16S ribosomal RNA. The results from these three studies showed the rod-shaped organisms to be a diverse group, not closely related to the cellulolytic, thermophilic members of the genus Clostridium. The phylogenetic study of representative isolates demonstrated this group of organisms to be a new sub-line of descent within the Clostridium/Bacillus subdivision of the gram positive bacteria. The results of this polyphasic approach allowed suggestions to be made as to the taxonomic position of these organisms. The isolation of the thermophilic spirochete and its designation to the genus Spirochaeta has extended the phenotypic and phylogenetic diversity of the organisms classified within the Spirochaetales. The phylogenetic study demonstrated the incoherence of the present taxonomy of the genus Spirochaeta. The Thermotoga-like isolate was shown to be a member of the genus Thermosipho on the basis of both phenotypic and phylogenetic characteristics. The isolation of this organism extended the geographical locations from which the members of the Thermotogales have been isolated.
User participation in the development of interorganisational systems and its effect on the success of such systems
(The University of Waikato, 1993) Cavaye, Angele L. M.; Cragg, Paul
This study focused on customer participation as one variable impacting on the adoption of systems which link organisations with their customers. The topic draws on literature concerning user participation in system development and, secondly, on literature relating to interorganisational and strategic systems. No previous research has focused on this research topic. Three related research questions were identified and investigated. The first question concerned antecedents which determine an organisation’s decision on whether or not to involve customers in the design and building of the system. The second question concerned the way in which customers participate in system development. The third question related to the effect of customer participation during development on adoption of the system. A multiple case approach was adopted for the empirical component of the study. Data was collected on 9 systems in New Zealand. Data analysis included within case analysis for each individual case and cross case analysis. It was found that customer participation during system design occurs in a minority of cases only and is associated with systems which are developed in response to customer initiatives or for competitive reasons. The effect of participation on subsequent adoption is indirect: participation can affect the ability of a system to fulfil a customer need and this need induces a customer to adopt the system. The study found that customer participation must be considered in relation to other adoption factors. A major outcome of the study is a model explaining and predicting adoption according to five adoption factors. If a system involves a customer in high acquisition costs, fast adoption is unlikely. The marketing effort by the sponsoring organisation and the technological awareness of the customer are strongly correlated with adoption.
Some aspects of the ecophysiology of Paulownia spp.
(The University of Waikato, 1993) Ede, Fiona Jean; Green, T.G. Allan; Silvester, Warwick B.
Members of the Paulownia genus have recently received widespread attention in New Zealand for their potential as special purpose timber trees and application in agroforestry systems. There has been only limited prior investigation of the ecophysiology of Paulownia. This study aimed to quantify aspects of gas exchange; biomass, nutrient and carbohydrate partitioning; and propagation and seedling establishment techniques in field grown and pot grown Paulownia trees, in Hamilton, New Zealand. Gas exchange measurements were undertaken using either a closed system LICOR 6200 unit or an open system Walz CMS 400 unit. Rates of gas exchange of Paulownia leaves under saturating light were high, with Aₘₐₓ in fully mature, non-senescent leaves ranging from 12 μmol m⁻² s⁻¹ to 25 μmol m⁻² s⁻¹, with gₛ between 0.2 mol m⁻² s and 0.8 mol m⁻² s⁻¹. The relationship between A and gₛ was variable which resulted in Cᵢ ranging from 190 μl 1⁻¹ to 280 μl 1⁻¹ under ambient CO₂ concentrations. High rates of transpiration were maintained in the large leaves to facilitate evaporative cooling under high radiation load. Leaf water potentials remained high throughout the day and, on the occasions when a midday depression of gas exchange rates was found, there was little evidence that it was a response to water stress. Circumstantial evidence suggested some form of negative feedback was involved in decreasing gas exchange rates in during the latter part of the day. Measurement of the ACᵢ response found low levels of stomatal limitation of photosynthesis, with l typically between 12% and 30%. The plants exhibited a number of characteristics of obligate sun plants, with the PPFDₛₐₜ of the leaves generally above 1000 μmol m⁻² s⁻¹. The pattern of biomass allocation, with a large proportion of the perennial tissues present as roots and the large investment in foliage, particularly in the establishment phase, was another feature typical of sun plants and enabled the plant to maintain a high growth rate. Growth rates were enhanced by the regular application of liquid fertilizer and frequent watering, and were higher in the warmer conditions of a glasshouse environment than outside. However, the temperature regime during leaf development had no effect on values of Aₘₐₓ. The temperature regime during growth did not affect the allocation of nutrients. In the field grown trees, the highest concentrations of all nutrients, except zinc, were found in the annual tissues, with foliar levels of nutrients in Paulownia similar to those reported for other timber species. Nitrogen levels in fully mature Paulownia leaves were generally between 2% and 2.5%, and within this range there was little correlation between nitrogen content and Aₘₐₓ. Nutrient levels in perennial tissues showed little change throughout each season, although nitrogen levels did increase in woody tissues at the end of each season. The levels of soluble sugars were high in all tissues of the Paulownia trees studied, in comparison with those found in other trees. The perennial root material stored large amounts of soluble sugars over the dormant season, with an average of 30% of the dry weight of the lateral roots found as soluble sugars at the last harvest of each season. The high soluble sugar content of these roots probably facilitated the growth of new root and shoot material when root cuttings were taken. The position of the root cutting in the parent root system had no effect on the regeneration capacity of the cutting. Cuttings with diameters less than 5 mm were less likely to regenerate than larger cuttings. Paulownia seedlings were found to suffer from transplant shock and generally grew more vigorously after transplanting if they were coppiced, rather than planted intact. Thus it was concluded that high rates of gas exchange and growth could be achieved by Paulownia trees if grown under conditions of high light, consistently warm temperatures, with frequent watering and the application of high rates of nutrients.
Privacy leakage quantification in vehicular ad hoc networks
(The University of Waikato, 2026) Daramas, Atthapan; Kumar, Vimal; Barcellos, Marinho
Vehicular Ad hoc Networks (VANETs) offer the benefits of enhancing road safety and efficiency through the frequent information exchange among vehicles through continuous broadcasting of their locations and kinematics. While VANETs can be a potential solution to reduce road accidents, frequently announcing locations raises concerns about user privacy, as vehicles may become targets of trajectory tracking, resulting in the exposure of sensitive locations visited by vehicle users. Several works in the literature have tackled the problem of privacy leakage and privacy preservation through mechanisms that use periodically changing pseudo-identities---known as pseudonyms in VANETs. However, most of this work was done before standards bodies, such as ETSI and SAE, developed VANET communication standards that described how messages should be formed and broadcast, and when pseudonyms should be changed. The use of VANET communication standards makes attempts by the research community to preserve users' privacy outdated and leaves the quantification of privacy leakage in VANETs unaddressed. By keeping communication standards as the context, this thesis aims to fill the gap in understanding potential privacy threats in VANETs and to quantify privacy leakage when these standards are enforced. We analyse potential VANET privacy threats using the LINDDUN framework — a privacy threat elicitation framework and uncover 13 privacy threats in VANET communication, ranging from unawareness of vehicle communication to privacy leakage through user reidentification when the full trajectory is reconstructed. The ability to reidentify a user's true identity from a reconstructed trajectory highlights two sides of the same coin in VANET privacy issues: privacy leakage through communication and the adversary's ability to reconstruct vehicle trajectories. Given the scarcity of real-world datasets, research on VANET privacy quantification can be hindered from being conducted in accordance with communication standardisations. We analyse two real-world VANET communication datasets and identify three limitations in these datasets that render them inadequate for VANET privacy quantification research. Therefore, we develop two VANET communication datasets based on the VANET communication standards from two major standards bodies, ETSI and SAE, to serve as substitutes for inadequate real-world datasets. Based on the findings from our privacy threat elicitation, three vehicle trajectory reconstruction models are developed to simulate privacy attacks against the standardised VANET communication. The three proposed trajectory reconstruction models include a path history-based approach, a Bayesian approach, and a Kalman filter approach. Our trajectory reconstruction models show that 65 to 98% of the trajectory can be fully reconstructed, where the amount of fully reconstructed trajectory depends on the tracking models and the communication standards. Our findings indicate that the VANET communication standards may not sufficiently protect users from privacy threats, as most of the trajectory can be reconstructed by the adversary, and highlight the need for enhanced privacy-preserving mechanisms that can be deployed alongside existing standards.
Integration of agricultural systems for environmental sustainability: Vermicomposting organic resources for waste management and food production in a circular economy
(The University of Waikato, 2026) Robertson, Charlotte; Lay, Mark; Gavin, Chanelle; Bertram, Danielle; Quintern, Michael
Food production creates organic waste. Dissolved air flotation (DAF) sludges from meat processing are problematic to dispose of; they are odorous, have high moisture contents and are rich in nutrients. Direct land application without stabilisation of nutrients is common. Paper wastes can often be recycled, but food-contaminated paper wastes are usually landfilled. Nutrients in these two organic resources are therefore usually wasted. This research demonstrated that the compost worm (Eisenia fetida Savigny) could produce vermicompost from novel mixtures of chicken DAF sludge and cardboard, meeting the New Zealand Standards for vermicasts and provided a beneficial effect on plant growth. This research investigated whether commercially produced vermicast applied to onions, potatoes and maize affected yield and/or quality over three consecutive years, with crop rotation on a market garden farm. While international field trials have shown vermicast to improve crop yields, this has not been investigated in rotational crop farming for maize, potatoes and onions. It also has not been conducted in New Zealand at the scale in this thesis. The treatments applied were annual applications of either chicken litter applied at 3 t fresh matter (FM)/ha, vermicast applied at 12.5 t FM/ha or 25 t FM/ha. The treatments were compared to a Control (normal farm management). All treatments, including the Control, received normal fertiliser rates. The trials showed that vermicast applied at 25 t fresh matter (FM)/ha increased onion density and yield (with estimated farmgate profit of >$800/ha), as well as maize grain kernel mass compared to the Control in the third season. This season was the driest, indicating the vermicast provided benefits to crops under abiotic stress. The chicken litter treatment reduced onion density in the second and third seasons. In the third season, this led to an increase in average onion bulb mass, but did not translate to an increase in yield above that of the Control. Additional glasshouse studies were conducted on the application of commercially produced vermicast to determine whether the method or timing of application impacted onion bulbs under glasshouse conditions. Another study investigated the potential for vermicast to supplement diammonium phosphate (DAP) fertiliser in a phosphorus (P) sparing trial in onions on a low Olsen P soil. Final soil Olsen P contents from treatments with 12.5 t FM/ha vermicast and 100% and 75% of recommended P were not significantly different to the Control (100% P and no vermicast). No effect of timing or supplementation of DAP was found on onion size or mass, though these trials were found to be underpowered. The effect of vermicast application timing in relation to crop production has not previously been investigated. Neither has the potential for vermicast to supplement imported phosphate fertiliser on low Olsen P soils. The outcome of this thesis is that beneficial vermicast can be produced from organic wastes and has potential to improve food production in New Zealand. It may also be possible to use vermicast to reduce reliance on conventional fertilisers such as DAP.
Learning strategies: testing Pask’s conversation theory in a computer environment
(The University of Waikato, 1993) Barbour, Robert H.; Ericksen, Neil; Katterns, Robert
Pask’s “Conversation Theory”, is an influential view of the nature of conversations between people, especially in learning situations. The theory provided a predictive framework within which to extend Pask’s laboratory work. Existing work used participant human observers to study the learning process. This technique may be unsuited to the normal classroom context. Software extensions to a geographical image library, map and data store, the BBC Domesday System, were used to extend Pask’s work. In carrying out this research, the three main principles from Conversation Theory were examined: 1) that people learn in different ways; 2) that the degree of matching between the learning strategies of teachers and learners strongly influences the rate of learning; and 3) that learning takes place as a conversation between participants whose essential features can be successfully automated. This thesis examined and evaluated three questions derived from Pask’s Conversation Theory in the light of empirical results collected in Phase 1 of a two phase research design. These questions were: 1) whether differences in learning preferences were detectable in modified versions of Ford’s (1985) questionnaire; 2) whether preferences for learning strategies were reflected in individual differences in learning behaviour; 3) whether matching learning preferences with learning experiences enhanced the learning process. Methods of investigation in Phase 1 included: a modified questionnaire; and using the BBC Domesday System to capture learning behaviour with a series of software tools. Findings show: that differences in learning preferences were detectable in questionnaire responses; that differences in learning behaviour were detected also in learning performances; that differences in preferences and behaviour were minimally correlated. Questions emerged from the lack of expected strength of agreement between findings of Phase 1. These questions are discussed in Phase 2 in relation to recent developments in both epistemology and the theory of computer science. The two further questions guiding the research in Phase 2 were: 4) whether matching learning and teaching strategies enhances learning; 5) whether a computer can act as a conversation participant in a teaching-learning context. Methods employed in Phase 2 include an examination of the findings of Phase 1 in the light of recent philosophical literature. Findings from Phase 2 show why matching is undecidable and why a computer cannot contribute to a conversation in the way a person does. Results in Phase 2 uphold Pask’s first principle, leave the second undecided and cast serious theoretical doubt on the third. The implications of the findings for educators, geographers and computer scientists are discussed.
Theoretical paradigms of understanding in accounting: from structuralism to pluralism
(The University of Waikato, 1993) Davey, Howard; Pratt, Michael; Lawrence, Stewart R.
Accounting thought has been largely driven by the immediate needs of accounting practitioners and hence the praxis of accounting has leaned heavily towards practice rather than theory. Resulting from this has been a loose patina of rules and conventions, frequently without articulation and frequently lacking detailed research and theorising. Two, at times overlapping, responses to this situation may be identified. One response can be described as the ‘professional’ or ‘institutional’ response, with researchers undertaking conceptual framework-type work which, although debatable, has provided little more than a political solution and has not adequately addressed the need for fundamental research and theory. The second response can be described as the development of theorising. Accounting researchers within this category in particular uplifted the scientific approach and have more recently considered alternative methods of gaining knowledge which are themselves reactions to the scientific approach. The purpose of the thesis is to examine and criticise the principal extant theoretical paradigms of understanding in accounting with a view to offering guidance for future researchers in accounting. In doing this a phenomenological approach is used. The thesis concludes that although there are strengths associated with the scientific approach, it is not universally appropriate nor does it confer any automatic legitimacy on the research. As a corollary, knowledge or understanding that has resulted from alternative approaches (whether they be interpretive case study or ethnomethodological research) should be included in the accounting body of knowledge. Further, by de-privileging the scientific approach researchers working in alternative areas do not then need to resort to the claim that their work is ‘scientific’ in order to gain ‘legitimacy’. The conclusion is that a pluralistic approach would liberate accounting from the privilege accorded to scientific research. As a consequence, this would impose a more stringent requirement on the researcher and the reader to study the objectives, setting and methodology of research. Liberating accounting research from the dominance of the scientific approach means that research can be discriminated on these bases. Results can then be evaluated in their own right without one technique being privileged over another. The importance of this conclusion is that the whole range of approaches to gaining knowledge is open to researchers - there is no prescription of one methodology or method, the positivist approach is not privileged over the ethnomethodological or vice versa. Consequently, a particular approach is held only as a belief statement by an individual and knowledge is recognised to be merely that which we believe it to be. Thus the ultimate conclusion of this thesis is that we need an open exchange of views and a more empathic attitude to understanding and analysis while not being tied to particular structures nor particular rules. Hence the title, Theoretical Paradigms of Understanding in Accounting: From Structuralism to Pluralism.
Formative evaluation of Heartbeat New Zealand
(The University of Waikato, 1992) Dehar, Mary-Anne Bailey; Thomas, David
A formative evaluation approach was applied over a 21 month period to Heartbeat New Zealand, an emergent heart disease prevention and health promotion programme. The aim of the research was to constructively influence the development of Heartbeat by providing ongoing evaluation input to the programme. Formative evaluation input involved two major aspects, of information collection and feedback, and consultation. Major data sources were interviews and questionnaires, direct participation and observation, and programme documents. It was found that while formative evaluation was only one source of influence upon the development of the Heartbeat programme, and formative evaluation findings and recommendations were not always accepted or fully implemented by programme personnel, positive outcomes of the formative evaluation input were apparent. In the Heartbeat Awards project, formative evaluation helped answer questions concerning the feasibility, appropriateness and effectiveness of an intervention aimed at creating and supporting behaviour change by altering environmental influences upon health. Formative evaluation of the Heartbeat Community Project identified the need for, and facilitated, the reorientation of the project from a traditional health educative approach to reflect more innovative health promotion strategies. Formative evaluation led to the development of a framework for later outcome evaluation of the overall Heartbeat programme which was tailored to the activities, characteristics and context of the programme. Formative evaluation activities identified problems in overall programme functioning in terms of programme management, planning and coordination, and communication, and action in these areas was recommended. The research both confirmed key points about formative evaluation identified in the evaluation literature, and highlighted further issues relating to the particular approach adopted in the Heartbeat programme. Major implications identified for future programmes were the importance of early and ongoing strategic planning and the importance of programme decision-makers adopting a model of information-based decision-making.
Trophic manipulation in freshwater plankton communities
(The University of Waikato, 1993) Edgar, Nick B.; Chapman, M. Ann
The effects of zooplankton herbivory on natural phytoplankton communities in two urban mesotrophic lakes in the North Island of New Zealand were studied over the course of one year. Lakes Rotoroa and Pupuke have zooplankton assemblages typical of most New Zealand lakes, in having a low species diversity, being dominated by calanoid copepods, and lacking Daphnia. In situ enclosure (limnocorral) experiments were conducted in each season of the year in each lake using 1 m³ (1000 litre) volume plastic bags. The enclosures were initially filled with lake water filtered through an 80 μm mesh plankton net to remove the majority of the zooplankton. Subsequently, a gradient of zooplankton biomass was established in eight enclosures by adding crustacean zooplankton collected from the epilimnion. Four densities (each duplicated) were established: exclosure (no zooplankton added), 1X, 2X, and 4X ambient zooplankton biomass. Experiments were conducted for 10 days with physico-chemical and biological sampling made on Days 0, 3, 6, and 10. Their aim was to investigate the role of zooplankton grazing on total algal biomass, the dynamics of population level responses of the phytoplankters, feeding selectivities of the herbivores and any changes in nutrient dynamics mediated by zooplankton grazing. In Lake Rotoroa zooplankton grazing had no significant effect on total algal biomass in autumn. In winter, spring and summer there were significant reductions in phytoplankton biomass particularly in the size fraction ≤ 80 μm. In Lake Pupuke grazing caused no change in algal biomass in autumn and winter, but in spring it was significantly reduced. However, in summer algal biomass was positively associated with zooplankton biomass possibly indicating that nutrient regeneration by zooplankters was important in this season. At the population level, algal species-specific response to herbivory varied between grazing suppression, a lack of response, increased abundance or in some cases, a unimodal response. The majority of phytoplankters in Lake Rotoroa were ‘decreasers’. In Lake Pupuke most algae were ‘unresponsive’ to grazing. Most ‘decreasers’ were of smaller size ≤ 30 μm in Greatest Axial Linear Dimension (GALD). ‘Unresponsive’ algae and ‘increasers’ were usually >30 μm in GALD. Relationships with algal biovolume were less consistent, but there was an upper limit to the volume of suppressed algae (~ 6,000 μm³) above which no species were significantly grazed. In Lake Rotoroa the presence of herbivores increased the availability of nitrogen (NH₄ and DON) in spring and of phosphorus (DRP and DOP) in summer. In Lake Pupuke zooplankton altered nutrient concentrations little during spring but increased the availability of both organic N and P during the summer experiment. The results suggest that integration of the ecological forces of grazing and nutrient limitation are required to explain patterns of planktonic seasonal succession, rather than depicting the two control processes as mutually exclusive.

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