Showing papers by "University of Auckland published in 1969"

Instability and river channels

Abstract: A linearized stability analysis of the flow of water in a channel with a loose bed and straight banks is described. It is assumed that the wavelength of the perturbations, which develop into meanders or braids, is longer than the width of the channel. It is therefore long compared with the ripples or dunes which cover the bed of such a channel and whose wavelength is shorter than the width of the channel. The latter need be allowed for only as roughness elements creating resistance. The variation of resistance to flow and rate of transport of bed material with velocity are discussed briefly and taken into account. Instability is interpreted as leading to a meandering or braided channel and it is shown that all practicable channels are unstable. Wavelengths calculated for channels expecte to meander are compatible with those given by Inglis's empirical rule and wavelengths calculated for channels which become braided are approximately the same as those observed.

Reading errors and self-correction behaviour

Abstract: Summary. If cues in redundant sources are cross-related it is often possible to detect that an error has been made. Evidence of self-correction behaviour in 5-year-old beginning readers is presented and the interpretation is made that an efficient information-processing strategy is developed by children who make good progress in learning to read. That such a strategy could be developed by young children at a stage of intuitive rather than logical thinking is best explained in terms of Neisser's concept of multiple thought processes which he considers appropriate for dealing with novel, irregular stimuli.

Oxidative-Addition Reactions of d8 Complexes

Abstract: Publisher Summary The rapid development of organo-transition-metal chemistry over the past decade has been dominated by considerations of bonding and structure. The reactions of such organo-metallic compounds have been discussed to a lesser extent and usually in the context of a particular metal or ligand. The apparent parallel between oxidative addition of covalent molecules to unsaturated d complexes and chemisorption of these molecules to the latent valences on transition metal surfaces may be significant. Several organic reactions that are homogeneously catalyzed by unsaturated d8 complexes involve oxidative addition FS a key step in the mechanism. An alternative pathway for five-coordinate complexes to undergo oxidative additions is through prior dissociation of a ligand to form a more reactive four-coordinate complex. Labilization of a ligand may be brought about by heating or irradiating a five-coordinate complex. The tendency for d complexes to undergo oxidative additions depends markedly on the nature of the central metal ion and the ligands attached to it.

Nitrogen Fixation by Gunnera–Nostoc Symbiosis

Abstract: THE genus Gunnera (Haloragaceae) contains forty species, all herbaceous, ten being endemic to New Zealand. Glands occurring at the bases of leaves become invaded by the blue-green alga Nostoc puntiforme1,2 which becomes intracellular3 and is capable of nitrogen fixation in culture2,4. Algal glands have been described for several New Zealand species5,6.

Free amino acid patterns and the classification of the Demospongiae

Abstract: An investigation of the free amino acid patterns of 67 species representing 50 genera of West Indian Demospongiae has been undertaken to examine the value of this biochemical approach in adding another parameter to phylogenetic inquiries. Two-dimensional thin-layer electrophoresis and chromatography were used to separate mixtures of naturally occurring ninhydrin-positive compounds. Individual components were identified as far as possible, and the fingerprints or patterns of the species studied were used as a basis for evaluating relationships. The subclass Ceractinomorpha is a relatively homogeneous group, with free amino acid patterns characterized by a consistent representation of protein amino acids and by the absence of compounds other than taurine and hypotaurine in the neutral region of the chromatogram. Two variants of this general pattern can be recognized, one found in the orders Dictyoceratida and Poecilosclerida, the other occurring in the order Haplosclerida and the family Halichondriidae of the order Halichondrida. Unexpected results within this subclass are the wide separation of the dictyoceratid families Spongiidae and Verongiidae, the anomolous patterns of the genera Agelas and Iotrochota and of the family Callyspongiidae, and the suggestive affinities of the family Hymeniacidonidae with the order Hadromerida. The subclass Tetractinomorpha appears to represent a polyphyletic assemblage in which 5 recognizable patterns can be distinguished. These represent the orders Homosclerophorida, Choristida, Spirophorida, Hadromerida and Axinellida. Of interest are the suggestions that the order Choristida is in itself a heterogeneous group, and that certain genera now placed in the order Axinellida may in fact be more closely related to the Poecilosclerida.

Variation in Form of Human Teeth: I. An Anthropologic and Forensic Study of Maxillary Incisors

Abstract: Qualitative analyses were made of morphologic variations in a large collection of extracted upper canine teeth. The range of variation negates the concept of a "typical tooth," but it also shows that certain characteristics tend to be found in a particular tooth of the dentition. This knowledge may be of anthropologic or forensic significance, especially to facilitate the identification of incomplete teeth.

Double-Stranded Viral RNA

Abstract: Publisher Summary The pace of research on RNA virus replication and the huge amount of related literature that has accumulated in the past 6 years attest to the wide interest in the topic. There has also been some controversy and apparent confusion, probably largely because of pressure for publication priority. In this chapter, methods for detecting, isolating, and characterizing double-stranded viral RNA are reviewed and recent results related to the isolation, identification, and replication of double-stranded RNA's in animal, plant, insect, and bacterial systems are discussed in the broad context of RNA virus replication. This chapter discusses each virus separately since this emphasizes more clearly on what is in fact established for a particular virus and what is inferred from other systems. Since much of the work on RNA phage replication prior to 1968 is being reviewed by Knolle and Franklin (this series), and is discussed in several earlier articles. Only certain aspects of RNA phage replication are considered in the chapter. Some properties of the viruses discussed in this chapter are summarized in a table.

The Biomorphology of Solomon Islands Shore with a Discussion of Zoning Patterns and Ecological Terminology

Abstract: The descriptive ecology of the Solomon Islands shores will be dealt with in a series of Reports from the marine party of the 1965 BSIP Expedition of the Royal Society, now in preparation This paper is a preliminary attempt to sketch out a biological classification of the shores of those Islands, and to set up some form of descriptive methodology in the light of the special character of the shores observed, in relation to existing zoning systems It must be followed by extended Reports on the adaptive ecology and the distribution of life forms in particular habitats

Petrology of the Waipapa Group, near Auckland, New Zealand

Abstract: The Waipapa Group of Permian-Jurassic age comprises a geosynclinal succession of lithic and feldspathic greywackes and argillites; cherts; and spilitic lavas. Low-grade metamorphism of these rocks has resulted in the development of a mineral assemblage characteristic of the prehnite-pumpellyite metagreywacke facies of Coombs (1960). The major detrital components of the greywackes are feldspar, quartz, lithic fragments, and a matrix. The composition of the greywackes is directly related to their grain size which in turn varies with bed thickness. The largely reconstituted matrix is considered of primary origin in massive, coarse-grained greywackes, but is in part secondary in most medium- and fine-grained rocks. The present study suggests that the conditions most conducive to the formation of a secondary matrix in metagreywackes are the presence of abundant labile detrital particles of fine sand-size, poor sorting, and low resistance of the rocks to shearing stresses. The sedimentary rocks represe...

A mycoplasma-like organism associated with phormium yellow leaf disease.

Abstract: Summary The phloem elements of Phormium tenax plants showing symptoms of yellow leaf disease in the field contain mycoplasma-like organisms. These appear to be confined to the phloem and are more numerous in rhizome phloem than in the roots or leaves. No mycoplasma-like organisms were found in healthy plants. Morphologically similar organisms were found in organs of most individuals of the plant hopper Oliarus atkinsoni collected from diseased plants in the field. The mycoplasma-like organisms were observed most frequently in the cells of the gut wall. Attempts to transmit yellow leaf disease with extracts containing the organisms were unsuccessful, as were attempts to culture them in vitro. No virus-like particles were seen in thin sections of cells from diseased plants.

Seasonal variation in phytoplankton from lake rotorua and other inland waters, New Zealand, 1966–67

Abstract: Summary Between, May 1966 and May 1967, 110 preserved samples of the phytoplankton of Lake Rotorua, New Zealand, were examined. Species and cell counts have been compared with data from Lakes Rotoiti (21 samples) and Ohakuri (36 net samples). Brief comparisons have also been made with the flora of two of the Wellington City reservoirs and the oxidation ponds at Mangere, Auckland. In Lake Rotorua the autumn, maximum was more pronounced than the spring maximum. Cell numbers inshore at Kawaha Point were consistently lower than those further out in the open lake. The phytoplankton is classified as a eutrophic formation of the diatom type, with Chlorophyceae as main subordinates. Dominants include Melosira granulata Ralfs (winter, spring, and autumn), Melosira distans (Ehr.) Kutz. (spring, summer, and autumn), and Asterionella formosa Hass. (summer and autumn).

The ambitious builder

Abstract: There are a surprising number of passages in Latin literature, especially of the .early Imperial period, in which the rich are castigated for wasting their wealth on all manner of follies, mansions that jut out over the sea and defy the boundaries of the elements, mountain-top retreats with flashing spires and golden ceilings, grandiose villas decorated with priceless mosaics, and the like. Yet most commentators, especially in school editions, seem content to let these passages pass with little more than a reference to the Romans' well known fondness for villas and their architectural capabilities in general. Admittedly there is strong documentation, both literary and archaeological, for the construction of immense, expensive houses in exotic locations, a late Republican fashion that seems to have developed almost into a mania under the Empire. Archaeologically, one thinks of the curious Grotto of Tiberius at Sperlonga or, at a later date, of Hadrian's Villa at Tivoli and the Roman Villa at Piazza Armerina in Sicily.1 For literary evidence Pliny ·theYounger is perhaps our best source. His Laurentine villa, described in such loving detail that even now it baffies all attempts at reconstruction, abutted right on to the shore so that in rough weather the waves would beat in upon the villa's seaward wall.2 He owned another of the same type on Lake Como from which he was able to fish ut e navicula and tells a gruesome story of a third on the same lake, which, projecting out over the water, provided the means of suicide for an incurable invalid and his wife.8 Such a story suggests that dwellings of this type were not restricted to the very rich, for Pliny, who prided himself on knowing everybody of note in his native district, had never heard of this couple. Furthermore it was some query about the legal position of such constructions, we may assume, that prompted Pliny's companion at the bar, Aristo, to deliver it as his opinion that 'what was built into the sea should be private property, just as what was filled by the sea, should be public.'4 However the number of references made by Roman writers to extravagance in building makes it clear that it soon became a commonplace of the literary artist, with different connotations for different writers. For instance, it is one of the few contemporary metaphors that Virgil employs in the Aeneid6 and is almost as

Unified Field Theory of Quarks and Electrons

Abstract: A unified gauge theory of quarks and electrons in which electromagnetic and strong interactions are both transmitted by the same vector field is formulated. It is argued that the theory is finite and that it is in agreement with observed electromagnetic and nuclear phenomena.

Respiratory metabolism in mangrove seedlings.

Abstract: The respiratory gaseous exchanges of detached whole mangrove seedlings (Avicennia, Bruguiera, Rhizophora) in a range of O(2) concentrations from 0 to 21% (air) were markedly reduced by the presence of external CO(2). Aerobic respiration decreased steadily for 16 days but the RQ remained at unity.In anoxia CO(2) output fell to half that in air. Ethanol accumulation was negligible but, relatively, acetaldehyde values were higher than in other tissues. Lactate accumulated initially but later decreased. On return to air CO(2) output was elevated above control values in a pattern resembling the previous lactate accumulation. The extent of the burst was too great, and the RQ too low, to be explained entirely by lactate oxidation.In 5 or 10% O(2) the CO(2) outputs were below those in anoxia and the RQ eventually rose to 1.4, suggesting the induction of fermentation. The absence of ethanol, acetaldehyde or lactate indicates that CO(2) was released from reactions other than those in the Embden-Meyerhof pathway.Tissue slice CO(2) outputs decreased with lowered O(2) concentrations and the RQ was always above unity except in air. The burst on return to air was absent, suggesting that slicing affects decarboxylation mechanisms.

The habits and habitats of the opisthobranch molluscs of the British Solomon Islands

Abstract: Often bizarre in shape and gaudily coloured, the opisthobranchs of the tropical IndoPacific have always been attractive subjects for the specialist worker and for writers of popular natural history. There is certainly no lack of papers describing their anatomy and systematics (Marcus & Burch (1965) give a fairly full bibliography), but only in those by Risbec (1928 a, b , 1951, 1953) are there descriptions of where or how they live and his statements are brief and rather vague. I collected opisthobranchs so as to record them for the British Solomon Islands for the first time and, whenever possible, I noted their habits and habitats. My observations on gut contents are rather scanty as I did not wish to damage any of the few specimens of each species collected. From an examination of ten different types of reef formation I discovered that opisthobranchs are common in only two places; (1) the crest of a semi-exposed reef where algae occur in pools, and (2) the flat of a sheltered or semi-sheltered reef. At each of these sites several distinct habitats can be distinguished. Unfortunately my recognition of these habitats is not supported by strong numerical evidence as none of the 55 species occurred in large numbers.

Ana〈110〉 +a〈001〉 dislocation pair in beta-brass

Abstract: Computation of theoretical electron diffraction images has confirmed the observation of an a〈110〉 + a〈001〉 dislocation pair in beta-brass. The pair probably results from the splitting of a 70° a〈111〉 dislocation, although elastic anisotropy theory predicts that the observed reaction is energetically neutral.

Recall of digits projected to temporal and nasal hemi-retinas

Abstract: Fourteen right-handed, right eye dominant subjects recalled digits when different ones were projected simultaneously to either temporal or nasal retinas. The principal findings were: (a) Recall of digits projected to nasal retinas was significantly better than when projected to temporal retinas; (b) information projected to the right eye was recalled significantly better than that projected to the left eye. It is shown that the relative ineffectiveness of the recall of input from the non-dominant eye can be attributed almost wholly to the relative inefficient recall of digits projected to the left temporal retina.

Anti-Christian Polemics in Seventeenth Century China

Abstract: In several articles and books published in recent years attempts have been made to examine the anti-Christian tradition in China and to seek for the causes of the failure of Christianity to substitute itself for the religious and philosophical traditions of the Chinese people. Reflective analyses of missionary policy and strategy, as well as of the Chinese milieu within which missionaries carried on their activities, have been made by theologians, historians and sociologists in order to determine what “went wrong.”