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Melissa M. Cadelis Soeren Geese Benedict B. Uy Daniel R. Mulholland Shara J. van de Pas Alex Grey Bevan S. Weir Brent R. Copp Siouxsie Wiles 《Molecules (Basel, Switzerland)》2021,26(4)
Antimicrobial bioassay-guided fractionation of the endophytic fungi Neofusicoccum australe led to the isolation of a new unsymmetrical naphthoquinone dimer, neofusnaphthoquinone B (1), along with four known natural products (2–5). Structure elucidation was conducted by nuclear magnetic resonance (NMR) spectroscopic methods, and the antimicrobial activity of all the natural products was investigated, revealing 1 to be moderately active towards methicillin-resistant Staphylococcus aureus (MRSA) with a minimum inhibitory concentration (MIC) of 16 µg/mL. 相似文献
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Melissa M. Cadelis Natasha S. L. Nipper Alex Grey Soeren Geese Shara J. van de Pas Bevan S. Weir Brent R. Copp Siouxsie Wiles 《Molecules (Basel, Switzerland)》2022,27(1)
Screening of several fungi from the New Zealand International Collection of Microorganisms from Plants identified two strains of Penicillium, P. bissettii and P. glabrum, which exhibited antimicrobial activity against Escherichia coli, Klebsiella pneumoniae, and Staphylococcus aureus. Further investigation into the natural products of the fungi, through extraction and fractionation, led to the isolation of five known polyketide metabolites, penicillic acid (1), citromycetin (2), penialdin A (3), penialdin F (4), and myxotrichin B (5). Semi-synthetic derivatization of 1 led to the discovery of a novel dihydro (1a) derivative that provided evidence for the existence of the much-speculated open-chained form of 1. Upon investigation of the antimicrobial activities of the natural products and derivatives, both penicillic acid (1) and penialdin F (4) were found to inhibit the growth of Methicillin-resistant S. aureus. Penialdin F (4) was also found to have some inhibitory activity against Mycobacterium abscessus and M. marinum along with citromycetin (2). 相似文献
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I. Bevan 《Journal of Polymer Science.Polymer Physics》1981,19(11):1759-1768
The finite-element method is applied to a craze model in order to estimate surface displacements and stresses of an isolated craze in a thin rectangular plate. The limitation of assuming linear-elastic behavior of the craze fibrils is demonstrated by comparing computed profiles with published experimental ones. Accurate finite-element estimates of craze surface stresses are obtained from the experimental displacement profile. The analysis is extended to the three-dimensional case but the difference between the craze displacements at the surface of the plate and those at midthickness is too small to justify the considerable increase in computer time in comparison with that required for two-dimensional analysis. 相似文献
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In this paper, the locally conservative Galerkin (LCG) method (Numer. Heat Transfer B Fundam. 2004; 46 :357–370; Int. J. Numer. Methods Eng. 2007) has been extended to solve the incompressible Navier–Stokes equations. A new correction term is also incorporated to make the formulation to give identical results to that of the continuous Galerkin (CG) method. In addition to ensuring element‐by‐element conservation, the method also allows solution of the governing equations over individual elements, independent of the neighbouring elements. This is achieved within the CG framework by breaking the domain into elemental sub‐domains. Although this allows discontinuous trial function field, we have carried out the formulation using the continuous trial function space as the basis. Thus, the changes in the existing CFD codes are kept to a minimum. The edge fluxes, establishing the continuity between neighbouring elements, are calculated via a post‐processing step during the time‐stepping operation. Therefore, the employed formulation needs to be carried out using either a time‐stepping or an equivalent iterative scheme that allows post‐processing of fluxes. The time‐stepping algorithm employed in this paper is based on the characteristic‐based split (CBS) scheme. Both steady‐ and unsteady‐state examples presented show that the element‐by‐element formulation employed is accurate and robust. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献