Showing papers by "University of Auckland published in 1984"
TL;DR: In this article, the authors trace the origins of this approach to Kurt Lewin and provide a synopsis of his views and compare Lewin's views on action research with those of contemporary exponents.
Abstract: Diverse claims have been made for and about action research in a variety of contexts. In this article, we first trace the origins of this approach to Kurt Lewin and provide a synopsis of his views. We then compare Lewin's views on action research with those of contemporary exponents. In the third section, we review and systematize the claims of 11 action researchers to determine the extent to which their claims constitute a shared conception. While most authors characterize action research as a methodology, a few also attempt to link action research to a particular interpretation or theory of social science. We build on this distinction in the final section and distinguish a weak from a strong version of action research, concluding that, at this time, neither version enjoys the status of a paradigm.
313 citations
TL;DR: The central TVZ has been active since 2 Ma and has erupted >104 km3 of dominantly rhyolitic magma during the last 1 m.y.p as mentioned in this paper.
Abstract: The Taupo volcanic zone (TVZ) has been active since 2 Ma and has erupted >104 km3 of dominantly rhyolitic magma during the last 1 m.y. Most of the volcanism is concentrated in a 125×60 km area forming the central TVZ and is expressed largely as six major caldera volcanoes, Rotorua, Okataina, Kapenga, Mangakino, Maroa, and Taupo, marked by localized collapse of the underlying basement and clustering of known or inferred vent sites. These centers have activity spans from 150 to 600 ka and have each erupted at least 300 to 1000 km3 of magma. All centers except Rotorua are known or inferred to have had complex histories of multiple caldera collapse, which have occurred alongside general basement collapse within the TVZ accompanying regional extension. Deep-seated NE trending basement lineations and/or faults have influenced vent sites at Okataina, Maroa, and Taupo. Welded ignimbrites are prominent in the pre-140 ka record; their absence since then is attributed to the effects of surface water on eruption styles rather than to a change in eruptive behavior. Volcanism from the centers has been overwhelmingly rhyolitic (>97% SiO2 69–77 wt%) with minor high-A1 basalt and dacite and traces of andesite, mostly as lithic fragments in ignimbrites from Okataina and Mangakino. Although insignificant in volume, the basalt is important as a low-Si end-member in mixing relationships with the rhyolite (at one extreme generating the dacites) and occasionally as a trigger for the rhyolitic eruptions. The current average rhyolite magma eruption rate from the central TVZ is ∼0.27 m3 s−1, equally divided between Okataina and Taupo, a figure close to the long-term average for the last 1.1 Ma. However, geothermal heat flow data imply that a further 1.4–1.8 m3 s−1 of magma may be intruded within the crust. The ratio of inferred intruded material to erupted material is higher at centers where lava extrusions are volumetrically significant (Okataina, Maroa), and this is correlated with lower phenocryst equilibration temperatures in the eruptives. Evidence for resurgent doming and long-term (>105 years) magma cycles documented at similarly sized rhyolitic calderas in the western United States is absent from the TVZ centers; this is attributed to the young faulted crust of the region, preventing the formation of sufficiently large high-level magma chambers. In overall terms, the central TVZ is comparable in size and longevity to the Yellowstone system, but its individual eruptions have very much shorter recurrence intervals and smaller volumes.
238 citations
TL;DR: In this article, the vibrational behavior of beam systems can be expressed in terms of waves of both propagating and near field types, and the effects of applied excitations are also considered.
234 citations
TL;DR: Maternal lupus anticoagulant activity has major implications for pregnancy and should be excluded in women with a clinical suspicion of SLE, a positive antinuclear antibody test, thrombotic episodes, biologically false‐positive VDRL and unexplained late or repetitive early fetal losses.
207 citations
TL;DR: A method is described by which the growth inhibitory effects of cytotoxic compounds on exponentially growing adherent cell lines can be quantitated, offering the advantage that any adherent cell line can be utilized without the need for tedious cell-counting procedures.
205 citations
TL;DR: If Σ has prime valency p, then either Σ is a bipartite graph or G2 acts regularly on Σ or G1 | G2 is a simple group which acts symmetrically on a graph ofValency p which can be constructed from Σ and does not have more vertices than Σ.
Abstract: Let G be a group acting symmetrically on a graph Σ, let G1 be a subgroup of G minimal among those that act symmetrically on Σ, and let G2 be a subgroup of G1 maximal among those normal subgroups of G1 which contain no member except 1 which fixes a vertex of Σ. The most precise result of this paper is that if Σ has prime valency p, then either Σ is a bipartite graph or G2 acts regularly on Σ or G1 | G2 is a simple group which acts symmetrically on a graph of valency p which can be constructed from Σ and does not have more vertices than Σ. The results on vertex-transitive groups necessary to establish results like this are also included.
184 citations
TL;DR: It is suggested that there are several factors operating at the time of or shortly after settlement, which result in spatial differences in recruitment on a very small scale, and the observed temporal variation may be due to a different set of factors operating prior to settlement and may have effects measurable over a considerably broader spatial scale.
154 citations
TL;DR: There was a significant correlation between collagen fibril diameter distribution, GAG type and amount, and functional load-bearing of the various skins, and that the variations in the biochemical and physical composition of the tissues at different stages of development could be related to both their post-conceptual maturity and their prospective functional loading.
Abstract: Samples of anatomically and functionally distinct regions of the skin of a variety of altricial and precocial animals were taken at various stages of development from birth to beyond maturity. The glycosaminoglycan (GAG) content and composition of the tissues were determined by chemical analysis and the collagen fibril diameters measured by transmission electron microscopy. The fibril diameters of the skins of two fish and a bird were also assessed for comparison. Analysis and comparison of the data collected show that there was a significant correlation between collagen fibril diameter distribution, GAG type and amount, and functional load-bearing of the various skins, and that the variations in the biochemical and physical composition of the tissues at different stages of development could be related to both their post-conceptual maturity and their prospective functional loading.
143 citations
01 Mar 1984
TL;DR: In this article, the authors examined the use of self-excited induction machines as low-cost stand-alone generators, including the problem of guaranteeing excitation, should remanent magnetism be lost.
Abstract: The paper examines the use of self-excited induction machines as low-cost stand-alone generators, including the problem of guaranteeing excitation, should remanent magnetism be lost. The behaviour of the generator under balanced and unbalanced conditions is analysed and the results used to evaluate the static VAR sources available to control the machine excitation. Experimental results for two static VAR sources and a variety of operating schemes are presented
124 citations
TL;DR: A register of new episodes of stroke was kept in the Auckland region for the year ending March 1982, with in-depth interviews at onset, one month and six months and a telephone follow-up at one year to establish dead or alive status.
Abstract: Death rates for cerebrovascular disease (stroke) in New Zealand are declining. To investigate the reasons for this decline and to measure the impact of stroke on a defined population, a register of new episodes of stroke was kept in the Auckland region for the year ending March 1982. All cases were followed for one year, with in-depth interviews at onset, one month and six months and a telephone follow-up at one year to establish dead or alive status. A total of 703 episodes were registered for 680 patients, 331 men and 349 women. The crude event rate for all those over 15 years was 228 and 220 per 100,000 for men and women, respectively. Age-adjusted event rates for all strokes were 28% higher for men than women and the age-adjusted event rates for Maoris were 44% higher than for non-Maoris. The case fatality rates were 23.1% at one week, 33.5% at one month, 43.5% at six months and 48.5% at one year. In comparison with other studies, case fatality rates are similar but the incidence rates appear to be lower.
124 citations
TL;DR: The temperate wrasse was studied in a shallow rocky reef habitat to asses how ecological and behavioural factors influence its within habitat patterns of distribution, with emphasis on examining the mechanisms underlying size/age related changes in dispersion and habitat use.
Abstract: The temperate wrasse, Pseudolabrus celidotus (Labridae), was studied in a shallow rocky reef habitat to asses how ecological and behavioural factors influence its within habitat patterns of distribution. Emphasis was placed on examining the mechanisms underlying size/age related changes in dispersion and habitat use. Juveniles (< 100 mm SL) were found to be aggregated whereas adults tended to be more randomly dispersed. This pattern appeared to be a product of both (a) ecological, and (b) behavioural factors. (a) Juveniles were closely associated with shelter (macro-algae) which was located in patches throughout the habitat. Their local distribution was probably not related to the distribution of their major prey items. Shelter dependence appears to decrease with growth and fish switched from feeding on micro-crustaceans present in macro-algae to those associated with bare rock — coralline turf areas. Adults foraged throughout larger home ranges, but fed preferentially in microhabitats where their prey items (e.g. bivalves) were most abundant. (b) Juveniles tended to aggregate into loose foraging schools. This tendency declined with age and was associated with a corresponding increase in the rate of aggressive interactions among individuals of a cohort. Consequently, individuals of the same size became more spaced out as they grew. Between cohort association or aggression was rare and apparently unimportant in determining local patterns of distribution. Many interspecific foraging associations and aggressive interactions were recorded. However, with the probable exception of interspecific territoriality by the blenny Forsterygion varium, these behaviours probably had only a transitory influence on the distribution of the wrasse.
01 Jan 1984
TL;DR: In the first half of pregnancy, genetic control is dominant and gives rise to relatively narrow limits of variability of patterns of fetal growth; in the second half ofregnancy, constraints and stimuli become increasingly important and give rise to greater variability of growth and of maturational milestones.
Abstract: Publisher Summary This chapter describes the regulation of fetal growth. The growth and development of the fetus is determined mainly by the fetal genome. Superimposed upon this genetic regulation of fetal growth are two opposing influences. On the one hand, fetal growth is constrained in various ways. The supply of nutrients to the fetus is limited by the capacity of the mother and placenta for supply and transfer, respectively. Other factors constraining fetal growth are poorly defined but are primarily maternal. On the other hand, a stimulus additional to the genetically determined drive to fetal growth and differentiation is provided by hormones and tissue growth factors. Thus, the rate of fetal growth represents the balance between constraining and stimulating forces acting on the genetically programmed drive to growth. In the first half of pregnancy, genetic control is dominant and gives rise to relatively narrow limits of variability of patterns of fetal growth; in the second half of pregnancy, constraints and stimuli become increasingly important and give rise to greater variability of growth and of maturational milestones.
TL;DR: In this article, the minimum duration for which two different stimuli must be presented if they are to be perceived as different, was measured for both auditory and visual stimuli, and the minimum durations were determined by means of a two- alternative forced-choice task for 50 children whose average age was 12 years 2 months.
TL;DR: In this paper, the authors present a method which predicts the deformation length under each roll station a priori by minimizing the energy consumption and assuming the material to be rigid-plastic.
TL;DR: The fatty acid content of 30 species of Porifera, including samples of Hexactinellida and Lithistida for which no fatty acid data previously existed, have been examined and peculiarities in proportions of individual acids of particular chain lengths distinguish the phylum.
TL;DR: The results imply that the stereotype of the stuttering personality, although mainly negative, may be derived not from motivational factors, but from judgments made under uncertainty.
Abstract: The purpose of this study was to test a hypothesis concerning the origin of the stereotype of the stuttering personality. According to this hypothesis the stereotype is formed by inference from bel...
TL;DR: It is demonstrated that embryonic chicken tendons can be maintained in a viable state in organ culture and may provide a useful model for studies of the effects of mechanical forces on the synthetic capability and structure of connective tissue cells.
Abstract: Digital flexor tendons isolated from 17–18 day embryonic chickens were cultured intact, either on steel mesh grids, or in an apparatus designed to apply a mechanical load to the tissue. Tendons cultured without an applied load continued to synthesize protein and glycosaminoglycans throughout a 7-day period, but DNA synthesis decreased during this time. Increases in both protein and DNA synthesis were observed in tendons experimentally loaded for 48–72 h.Glycosaminoglycan production by tendons isolated from 17-day embryos was also increased in loaded tendons, sulfated GAG being increased more than hyaluronic acid. The same loading regime applied to tendons from 18-day embryos produced a smaller, yet significant increase in sulfated glycosaminoglycans but hyaluronate production was reduced.These investigations demonstrate that embryonic chicken tendons can be maintained in a viable state in organ culture and may provide a useful model for studies of the effects of mechanical forces on the synthetic capabili...
TL;DR: One stage in the Austronesian settlement of the Pacific is associated with the reconstructed language known as Proto Oceanic (POC), which is regarded by linguists as the immediate ancestor of a subgroup which contains more than 400 languages as mentioned in this paper.
Abstract: scattered almost two-thirds of the way round the tropical and subtropical world?was a feat with only one parallel in human history: the expansion of West European peoples after Columbus. In each case advances in sailing methods by maritime peoples, speakers ofa single language family originally living on continents or continental islands, enabled them to undertake long ocean voyages to explore and trade, and led to their rapid colonization of farflung lands.1 Yet the Austronesian expansion was more or less completed long before Columbus, and the challenge of reconstructing its course is more akin to that of reconstructing the original Indo-European expansion across Eurasia after 3500 B.C. We are dealing with prehistoric events and cir cumstances whose outlines may be recovered only by careful application of the methods available to prehistorians, especially those of archaeology and comparative-historical linguistics. This paper will focus on one stage in the Austronesian settlement of the Pacific ?that associated with the reconstructed language known as Proto Oceanic (POC). What makes this stage of particular importance is that Proto Oceanic is regarded by linguists as the immediate ancestor ofa subgroup which contains more than 400 languages, or about half the Austronesian total. The subgroup coincides almost exactly with those members of Austronesian that are spoken in the southwest and central Pacific. Into Oceanic fall nearly ail of the so-called Melanesian languages,2 plus the Polynesian group and the Microne sian languages other than Chamorro, Belauan (Palauan) and possibly Yapese. No Oceanic languages are found west of New Guinea. The boundary line bet ween the Oceanic group and the rest of Austronesian runs through the north coast of New Guinea between 136? and 138? E (east of the Bird's Head, bet ween Sarera Bay and the Sarmi Coast), and curves through the western islands of Micronesia between 132? and 140? E (see Figure 1).
TL;DR: In the Cuyama Gorge and southern La Panza Range of west-central California, alluvial fan conglomerates of the middle Cenozoic Simmler Formation were deposited in two half-graben basins.
TL;DR: The aqueous micelle model and its relation to the various models proposed for aggregation of surfactants in nonaqueous solvents, and the controversy surrounding the applicability of the critical micelle concentration to these aggregates, have been discussed in this paper.
TL;DR: A calibration technique is presented that enables absolute estimates of total body nitrogen (TBN) to be made using prompt gamma IVNAA in critically ill patients with gross abnormalities in body composition, especially in their state of hydration.
Abstract: A programme of metabolic and nutritional research is being undertaken in critically ill patients requiring intensive care. Central to this research is the measurement of the three nutritionally important compartments of body composition, protein, fat, and water by a combination of tritium dilution and prompt gamma in vivo neutron activation analysis (IVNAA). In this paper a calibration technique is presented that enables absolute estimates of total body nitrogen (TBN) to be made using prompt gamma IVNAA in critically ill patients with gross abnormalities in body composition, especially in their state of hydration. This technique, which is independent of skinfold anthropometry and does not make a priori assumptions about the ratios of major body compartments, has been applied to 41 normal volunteers and the derived values for nitrogen compared with values obtained by applying three currently used calibration methods to the same experimental data; the other methods are used at centers which also measure nitrogen by prompt gamma IVNAA. Close agreement is obtained between the four calibration methods, with correlation coefficients relative to the Auckland technique of 0.999, 0.998, and 0.994. In addition, the measured values of TBN are compared to values obtained for the same group of volunteers using sets of empirical equations from two centers, one of which uses prompt gamma IVNAA (Brookhaven National Laboratory, Long Island, USA) and the other delayed gamma IVNAA (Leeds, Britain). The empirical equations relate TBN in normal people to age, height, weight and sex. The mean ratios of experimental to predicted TBN (with SEMs) are 1.013 ± 0.017 and 1.002 ± 0.014, respectively. Mean values of the ratio of TBN to fat-free mass (0.0340 ± 0.0004) and of total body water to fat-free mass (0.716 ± 0.002) agree closely with values reported elsewhere for normals by a variety of techniques including chemical analysis. Finally, TBN results based on the four different calibration methods are presented for five surgical patients, demonstrating the importance of the calibration method on estimates of TBN in patients with abnormal body composition. It is concluded that this technique will provide accurate estimates of the total body content of protein, water, and fat in intensive care patients.
TL;DR: The surgical results of left ventricular aneurysmectomy have been examined in 145 patients during a 13 year period and the chances of hospital death were increased by worsening New York Heart Association (NYHA) class, severe congestive heart failure (CHF), and extensive coronary disease.
TL;DR: Seasonal fluctuations in growth rate, haptera formation, frond size and sporulation were delayed in plants in deeper water in dense populations at 7-m depth.
Abstract: Ecklonia radiata (C. Ag.) J. Ag. growing in Goat Island Bay, New Zealand produced up to 6 kg dry weight of tissue m-2 yr-1 in dense populations at 7-m depth. Half this tissue and an unknown amount of exudates were sloughed or torn off. Tissue production at 15 m was 0.3 to 0.5 kg m-2 yr-1. At this depth the plants grew only half as fast as in shallow water and the population density was decreased. Approximately 20% by weight of tissue produced at 7 m and 10% of that at 15 m was reproductive tissue. At both depths the elongation rate and percentage of water in stipes varied with stipe size. Initial sorus formation was related to plant size and not to age. Seasonal fluctuations in growth rate, haptera formation, frond size and sporulation were delayed in plants in deeper water.
TL;DR: Blood oxygen-binding properties are discussed in relation to the polar environment, mode of life, and the concept of cold adaptation in antarctic fish.
Abstract: 1.The effects of thermal acclimation on whole blood oxygen affinity were examined in the antarctic fish Pagothenia borchgrevinki . 2.4.5°C-acclimated fish had a P 50 value of 26.7 mmHg at pH 8.1, compared to 20.7 mmHg for −1.5°C-acclimated fish. The apparent heat of oxygenation, ΔH = −26.7 kJ mol −1 , is comparable to values for temperate species. 3.Warm-acclimation was followed by an increased ATP: Hb 4 molar ratio, resulting in an augmentation of the thermal effect on oxy-haemoglobin affinity. This may be considered adaptive in a constantly well oxygenated environment, where oxygen loading at the gills is secured. Unloading to the tissues is thereby enhanced, supporting an elevated rate of aerobic metabolism at higher temperatures. 4. In vivo blood pH was high, between 8.10 and 8.25 at −1.5°C. Astrup titration revealed arterial CO 2 tensions of less than 0.8 mmHg, indicating relative hyperventilation and low oxygen extraction efficiency in antarctic fish. 5.Blood oxygen affinities of four antarctic nototheniid species were low (P 50 between 11.9 and 20.7 mmHg at pH 8.1 and --1.5°C) in comparison with the temperate species Notothenia angustata (P 50 = 10.8 mmHg). The zoarcid Rhigophila dearborni had a high blood oxygen affinity (P 50 = 4.3 mmHg). Blood oxygen-binding properties are discussed in relation to the polar environment, mode of life, and the concept of cold adaptation.
TL;DR: A reanalysis of the published data indicates that the PCC-10 (10% response rate) for cadmium in kidney cortex is likely to be in the range 180-220 micrograms/g and thePCC-50 is likelyto be about 25% higher.
29 Mar 1984-Journal of Comparative Physiology A-neuroethology Sensory Neural and Behavioral Physiology
TL;DR: Maximum swimming speeds in antarctic fish are close to speeds predicted by extrapolation to the same temperature from temperate fishes, but saccade velocities are higher than predicted.
Abstract: Velocities of swimming and eye movements were measured in several species of nototheniid fish living at −1.9 °C in McMurdo Sound, Antarctica.
1.
The most common mode of swimming was labriform. The speed of labriform swimming inPagothenia borchgrevinki, a cryopelagic species, was a linear function of pectoral fin beat frequency, reaching a maximum of 38 cm s−1 (1.8 L s−1) at a fin beat frequency of about 2 Hz (Fig. 2).
2.
Subcarangiform swimming was employed for short dashes and escape responses. In this modeP. borchgrevinki attained a maximum swimming speed of 110 cm s−1 (4.9 L s−1) at a caudal fin beat frequency of 5.7 Hz.
3.
The maximum amplitude of saccadic eye movements was about 20° inP. borchgrevinki, and 30° in the benthic speciesTrematomus bernacchii andT. centronotus. In all 3 species, amplitude was correlated with saccade velocity (Fig. 6).
4.
Saccade velocities were variable compared with those of mammals. Outward saccades (away from the resting position of the eye) were slower than return saccades of the same amplitude. The maximum velocity of outward saccades was about 50 deg s−1; that of return saccades was about 120 deg s−1.
5.
Maximum swimming speeds in antarctic fish are close to speeds predicted by extrapolation to the same temperature from temperate fishes, but saccade velocities are higher than predicted. The difference is attributed to a relative lack of temperature compensation in muscle, while there is a greater degree of compensation in the central nervous system.
TL;DR: A detailed account of symptoms produced by Colletotrichum gloeosporioides on susceptible and resistant cultivars of yam (Dioscorea alata) in Solomon Islands is given and it is inappropriate to retain the epiphet f.
Abstract: A detailed account of symptoms produced by Colletotrichum gloeosporioides on susceptible and resistant cultivars of yam (Dioscorea alata) in Solomon Islands is given. A superficial blackening of upper leaf surfaces of some cultivars is unusual and worthy of further study. In pathogenicity tests with isolates of C. gloeosporioides from various sources, those that were virulent on D. alata were all from D. alata except one from D. esculenta and one from Cucumis sativus but only nine of 30 isolates from D. alata were virulent on this host. Since all four isolates of the yam pathogen tested on D. nummularia and D. trifida were virulent, it is inappropriate to retain the epiphet f. sp. alatae proposed by earlier authors. Considerable variation in cultural morphology existed among virulent isolates, the only consistent character being production of dark pigment, although this was also produced by some saprophytic isolates. Most reisolations of C. gloeosporioides from lesions resulting from inoculation yielded isolates identical with the original inoculum but also some reisolates had a different morphology.
TL;DR: A number of force fields of the molecular mechanics type have been tested for their ability to represent as an energy minimum, the observed crystal structure for three cyclic hexapeptides as mentioned in this paper.
Abstract: A number of force fields of the molecular mechanics type have been tested for their ability to represent as an energy minimum, the observed crystal structure for three cyclic hexapeptides, cyclo-(-Ala-Ala-Gly-Gly-Ala-Gly-), cyclo-(-Ala-Ala-Gly-Gly-Ala-Gly-), and cyclo-(-D-Ala-D-Ala-Gly-Gly-Gly-Gly-). The most effective force field tested was that recently proposed by Kollman and co-workers, notwithstanding its use of “united” atoms for CH, CH2, and CH3 groups. Fields proposed by Levitt, and adaptations of that of Scheraga and co-workers, were also effective. Force fields in which hydrogens bonded to electronegative atoms were not specified explicitly were less accurate in representation.
TL;DR: There is an increase in the responsiveness of the uterine-PGF secretory system to oxytocin during the latter stages of the estrous cycle and during early pregnancy this response was blocked by the presence of the embryo.
Abstract: This study was undertaken to determine the effect of exogenous oxytocin on plasma concentrations of the prostaglandin (PG) F metabolite 13,14-dihydro-15-keto-PGF (PGFM) and the oxytocin-associated neurophysin (OT-N) during the estrous cycle and early pregnancy in the ewe. Ewes were given oxytocin (250 mU, i.v.) on Days 3 (n = 4), 8 (n = 5), 13 (n = 4) or 14 (n = 5) of the estrous cycle, and a further 6 ewes were injected on Days 13 (n = 2) and 14 (n = 4) of pregnancy. No significant rises in plasma concentrations of PGFM were observed on Days 3 and 8 of the estrous cycle and on Days 13 and 14 of pregnancy. A marked increase in plasma PGFM concentrations occurred on Day 14 of the estrous cycle with the PGFM levels rising from a mean basal value of 120 pg/ml to a mean maximum value of 415 pg/ml within 2-10 min of administering oxytocin (P less than 0.001). No increases in plasma OT-N concentrations were found in early pregnancy and only 1 of 4 ewes at Day 14 of the cycle showed any significant increase in OT-N concentrations. It is concluded that there is an increase in the responsiveness of the uterine-PGF secretory system to oxytocin during the latter stages of the estrous cycle. During early pregnancy this response was blocked by the presence of the embryo.(ABSTRACT TRUNCATED AT 250 WORDS)