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931.
We formalise and present a new generic multifaceted complex system approach for modelling complex business enterprises. Our method has a strong focus on integrating the various data types available in an enterprise which represent the diverse perspectives of various stakeholders. We explain the challenges faced and define a novel approach to converting diverse data types into usable Bayesian probability forms. The data types that can be integrated include historic data, survey data, and management planning data, expert knowledge and incomplete data. The structural complexities of the complex system modelling process, based on various decision contexts, are also explained along with a solution. This new application of complex system models as a management tool for decision making is demonstrated using a railway transport case study. The case study demonstrates how the new approach can be utilised to develop a customised decision support model for a specific enterprise. Various decision scenarios are also provided to illustrate the versatility of the decision model at different phases of enterprise operations such as planning and control. 相似文献
932.
Michael F. Jobling Colin J. Barrow Anthony R. White Colin L. Masters Steven J. Collins Roberto Cappai 《Letters in Peptide Science》1999,6(2-3):129-134
A peptide corresponding to residues 106-126 of the human prion protein (PrP) possesses the neurotoxic and amyloidogenic properties of the infectious form of the parental protein. This peptide is now identified as a 'difficult sequence' and synthesis using conventional manual Fmoc chemistry was unsuccessful with acylation terminating at a central core of hydrophobic amino acids. The use of tetramethylfluoroformamidinium hexafluorophosphate and 1-methyl-2- pyrrolidone as anti-aggregatory agents in the coupling steps improved the synthesis but still resulted in an incomplete peptide. The incorporation of N-(2-hydroxy-4-methoxybenzyl) protection at glycine residues 119 and 124 enabled synthesis of the full length peptide in low yield. Synthesis using Boc chemistry with in situ neutralisation gave the full length peptide in high yield. 相似文献
933.
A 2.3-kb DNA fragment cloned from plasmid pCH200, the largest (52 kb) of four plasmids detected in Staphylococcus xylosus, was found to confer resistance to 14-membered ring macrolides in Bacillus subtilis and Staphylococcus aureus. DNA-sequence analysis of the fragment revealed the presence of an open-reading frame, the deduced product of which was identical to one of the two ATP-binding domains encoded by the macrolide/streptogramin-B-resistance gene msrA of Staphylococcus epidermidis. The observation that a polypeptide homologous to the C-terminus of MsrA is capable of mediating erythromycin resistance in the absence of the N-terminal region is of significance both to the evolution and functional activity of members of the ATP-binding transport super-gene family. 相似文献
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936.
Mitchell T. Irwin Jean-Luc Raharison David R. Raubenheimer Colin A. Chapman Jessica M. Rothman 《PloS one》2015,10(6)
Animals experience spatial and temporal variation in food and nutrient supply, which may cause deviations from optimal nutrient intakes in both absolute amounts (meeting nutrient requirements) and proportions (nutrient balancing). Recent research has used the geometric framework for nutrition to obtain an improved understanding of how animals respond to these nutritional constraints, among them free-ranging primates including spider monkeys and gorillas. We used this framework to examine macronutrient intakes and nutrient balancing in sifakas (Propithecus diadema) at Tsinjoarivo, Madagascar, in order to quantify how these vary across seasons and across habitats with varying degrees of anthropogenic disturbance. Groups in intact habitat experience lean season decreases in frugivory, amounts of food ingested, and nutrient intakes, yet preserve remarkably constant proportions of dietary macronutrients, with the proportional contribution of protein to the diet being highly consistent. Sifakas in disturbed habitat resemble intact forest groups in the relative contribution of dietary macronutrients, but experience less seasonality: all groups’ diets converge in the lean season, but disturbed forest groups largely fail to experience abundant season improvements in food intake or nutritional outcomes. These results suggest that: (1) lemurs experience seasonality by maintaining nutrient balance at the expense of calories ingested, which contrasts with earlier studies of spider monkeys and gorillas, (2) abundant season foods should be the target of habitat management, even though mortality might be concentrated in the lean season, and (3) primates’ within-group competitive landscapes, which contribute to variation in social organization, may vary in complex ways across habitats and seasons. 相似文献
937.
Colin R. Andrew Jane Han Tanneke den Blaauwen Gertie van Pouderoyen Erik Vijgenboom Gerard W. Canters Thomas M. Loehr J. Sanders-Loehr 《Journal of biological inorganic chemistry》1997,2(1):98-107
In the redox center of azurin, the Cu(II) is strongly coordinated to one thiolate S from Cys 112 and two imidazole Ns from
His 46 and 117. This site yields a complex resonance Raman (RR) spectrum with >20 vibrational modes between 200 and 1500 cm–1. We have investigated the effects of ligand-selective isotope replacements on the RR spectrum of Pseudomonas aeruginosa azurin to determine the relative spectral contribution from each of the copper ligands. Growth on 34S-sulfate labels the cysteine ligand and allows the identification of a cluster of bands with Cu–S(Cys) stretching character
between 370 and 430 cm–1 whose frequencies are consistent with the trigonal or distorted tetrahedral coordination in type 1 sites. In type 2 copper-cysteinate
sites, the lower ν (Cu–S) frequencies between 260 and 320 cm–1 are consistent with square-planar coordination. Addition of exogenous
15N-labeled imidazole or histidine to the His117Gly mutant generates type 1 or type 2 sites, respectively. Because neither the
above nor the His46Gly mutant reconstituted with 15N-imidazole exhibits significant isotope dependence, the histidine ligands can be ruled out as important contributors to the
RR spectrum. Instead, a variety of evidence, including extensive isotope shifts upon global substitution with 15N, suggests that the multiple RR modes of azurin are due principally to vibrations of the cysteine ligand. These are resonance-enhanced
through kinematic coupling with the Cu–S stretch in the ground state or through an excited-state A-term mechanism involving
a Cu-cysteinate chromophore that extends into the peptide backbone.
Received: 29 July 1996 / Accepted: 9 November 1996 相似文献
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940.
Colin Bibby 《Ibis》1995,137(S1):S247-S248