19 research outputs found

    Evolution of New Zealand's terrestrial fauna: a review of molecular evidence

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    New Zealand biogeography has been dominated by the knowledge that its geophysical history is continental in nature. The continental crust (Zealandia) from which New Zealand is formed broke from Gondwanaland ca 80鈥奙a, and there has existed a pervading view that the native biota is primarily a product of this long isolation. However, molecular studies of terrestrial animals and plants in New Zealand indicate that many taxa arrived since isolation of the land, and that diversification in most groups is relatively recent. This is consistent with evidence for species turnover from the fossil record, taxonomic affinity, tectonic evidence and observations of biological composition and interactions. Extinction, colonization and speciation have yielded a biota in New Zealand which is, in most respects, more like that of an oceanic archipelago than a continent

    Antibacterial and Antifugal Mono- and Di-substituted Symmetrical and Unsymmetrical Triazine-derived Schiff-bases and their Transition Metal Complexes

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    A new series of antibacterial and antifungal triazine-derived mono- and di-substituted (symmetrical and unsymmetrical) Schiff-bases and their cobalt(II), copper(II), nickel(II) and zinc(II) metal complexes have been synthesized and characterized by their elemental analyses, molar conductances, magnetic moments and IR and electronic spectral measurements. IR spectra indicated the ligands to act as tridentate towards divalent metal ions via a trazine-N, the azomethine-N and, indole-NH and deprotonated-O of salicylaldehyde. The magnetic moments and electronic spectral data suggest octahedral geometry for the Co(II), Ni(II) and Zn(II)complexes and square-pyramid for Cu(II) complexes. NMR spectral data of the ligands and their diamagnetic zinc(II) complexes well-define their proposed structures/geometries. Elemental analyses data of the ligands and metal complexes agree with their proposed structures/geometries. The synthesized ligands, along with their metal complexes were screened for their antibacterial activity against Escherichia coli, Bacillus subtillis, Shigella flexneri, Staphylococcus aureus, Pseudomonas aeruginosa and Salmonella typhi and for antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. The results of these studies show the metal complexes to be more antibacterial/ antifungal against two or more species as compared to the uncomplexed Schiff-base ligands

    On the flexibility of letter position coding during lexical processing: evidence from eye movements when reading Thai

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    Previous research supports the view that initial letter position has a privileged role in comparison to internal letters for visual-word recognition in Roman script. The current study examines whether this is the case for Thai. Thai is an alphabetic script in which ordering of the letters does not necessarily correspond to the ordering of a word\u27s phonemes. Furthermore, Thai does not normally have interword spaces. We examined whether the position of transposed letters (internal, e.g., porblem, vs. initial, e.g., rpoblem) within a word influences how readily those words are processed when interword spacing and demarcation of word boundaries (using alternatingbold text) is manipulated. The eye movements of 54 participants were recorded while they were reading sentences silently. There was no apparent difference in degree of disruption caused when reading initial and internal transposed-letter nonwords. These findings give support to the view that letter position encoding in Thai is relatively flexible and that actual identity of the letter is more critical than letter position. This flexible encoding strategy is in line with the characteristics of Thai鈥攖hat is, the flexibility in the ordering of the letters and the lack of interword spaces, which creates a certain level of ambiguity in relation to the demarcation of word boundaries. These findings point to script-specific effects operating in letter encoding in visual-word recognition and reading
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