933 resultados para evolving
Resumo:
Peroxisomes are small subcellular compartments that utilize proteins manufactured in the cytoplasm. Proteins use one of two peroxisomal import pathways. This paper presents a simple evolutionary search for a motif that describes the signal used by one of the two pathways: PTS2. The evolved motif has a discriminative accuracy exceeding previously manually curated motifs and can be used to screen genomic data for putative peroxisomal proteins.
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This paper is concerned with three evolving disciplines, namely, Management of Technology (MoT), Operations Management (OM) and Supply Chain Management (SCM). These three disciplines have emerged at different times, SCM being the most recent, although they also seem to be concerned, at least in some part, with the same managerial problem areas. Based on this underlying assumption, the paper lays the ground for this special issue of the International Journal of Technology Management, which is devised to provide a platform for discussion concerning the impacts, relationships and possible synergies between the three disciplines that very much seem to be driving the attention of a lot of recent management thinking.
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This contribution explores notions of sovereignty in the three French territories of the South Pacific: French Polynesia, New Caledonia, and Wallis and Futuna. It also analyses the key nuances and challenges of the transition from aspirations of 'independence' to those of 'shared sovereignty'. From protectorates or colonies to overseas territories (Territoires d'Outre-Mer), these three territories have experienced specific and customised statuses with various degrees of autonomy, all underscoring a fine line between autonomy and sovereignty. Indeed, 'sovereignty' has today become much more synonymous with the concept of 'self-government' or 'large autonomy', as the current situation in French Polynesia demonstrates. Meanwhile, New Caledonia is one step closer to 'full sovereignty', since its actual status includes provisions for a referendum on self-determination between 2014 and 2018. The claim for independence, a characteristic of Kanak and Maohi movements, has become more pragmatically focused, to the extent that considering sovereignty 'in free-association' with France is now a perfectly conceivable option. © 2012 Copyright Taylor and Francis Group, LLC.
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The research investigates the past, present and potential future role of Information Specialists (ISps) in process oriented companies. It tests the proposition that ISps in companies that have undertaken formal process reengineering exercises are likely to become more proactive and more business oriented (as opposed to technically oriented) than they had previously been when their organisations were organised along traditional, functional lines. A review of existing literature in the area of Business Process Reengineering and Information Management reveals a lack of consensus amongst researchers concerning the appropriate role for ISps during and after BPR. Opinion is divided as to whether IS professionals should reactively support BPR or whether IT/IS developments should be driving these initiatives. A questionnaire based ‘Descriptive Survey’ with 60 respondents is used as a first stage of primary data gathering. This is followed by follow-up interviews with 20 of the participating organisations to gather further information on their experiences. The final stage of data collection consists of further in-depth interview with four case study companies to provide an even richer picture of their experiences. The results of the questionnaire are analysed and displayed in the form of simple means, frequencies and bar graphs. The ‘NU-DIST’ computer based discourse analysis package was tried in relation to summarising the interview findings, but this proved cumbersome and a visual collation method is preferred. Overall, the researcher contends that the supposition outlined above is proven, and she concludes the research by suggesting the implications of these findings. In particular she offers a ‘Framework for Understanding and Action’ which is deemed to be relevant to both practitioners and future researchers.
Resumo:
Orthodox contingency theory links effective organisational performance to compatible relationships between the environment and organisation strategy and structure and assumes that organisations have the capacity to adapt as the environment changes. Recent contributions to the literature on organisation theory claim that the key to effective performance is effective adaptation which in turn requires the simultaneous reconciliation of efficiency and innovation which is afforded by an unique environment-organisation configuration. The literature on organisation theory recognises the continuing confusion caused by the fragmented and often conflicting results from cross-sectional studies. Although the case is made for longitudinal studies which comprehensively describe the evolving relationship between the environment and the organisation there is little to suggest how such studies should be executed in practice. Typically the choice is between the approaches of the historicised case study and statistical analysis of large populations which examine the relationship between environment and organisation strategy and/or structure and ignore the product-process relationship. This study combines the historicised case study and the multi-variable and ordinal scale approach of statistical analysis to construct an analytical framework which tracks and exposes the environment-organisation-performance relationship over time. The framework examines changes in the environment, strategy and structure and uniquely includes an assessment of the organisation's product-process relationship and its contribution to organisational efficiency and innovation. The analytical framework is applied to examine the evolving environment-organisation relationship of two organisations in the same industry over the same twenty-five year period to provide a sector perspective of organisational adaptation. The findings demonstrate the significance of the environment-organisation configuration to the scope and frequency of adaptation and suggest that the level of sector homogeneity may be linked to the level of product-process standardisation.
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Divisia money is a monetary aggregate that gives each component asset an assigned weight. We use an evolutionary neural network to calculate new Divisia weights for each component utilising the Bank of England monetary data for the U.K. We propose a new monetary aggregate using our newly derived weights to carry out quantitative inflation prediction. The results show that this new monetary aggregate has better inflation forecasting performance than the traditionally constructed Bank of England Divisa money. This result is important for monetary policymakers, as improved construction of monetary aggregates will yield tighter relationships between key macroeconomic variables and ultimately, greater macroeconomic control. Research is ongoing to establish the extent of the increased information content and parameter stability of this new monetary aggregate.
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This paper outlines, using evidence from several case studies, the use of alternative forms of manufacturing strategy processes. Our investigation shows that the manufacturing strategy development practices of manufacturers are evolving in many directions; we found several alternatives to the formal top-down planning process. Manufacturers use one or more of the following alternatives with or without the top-down manufacturing strategy process: a coherent pattern of actions; manufacturing/process improvement programs; or the pursuit of core manufacturing capabilities. It appears that the various manufacturing strategy development processes may be tied to the strategic role of manufacturing in a company. This paper offers a framework that captures the relationship between the strategic role of manufacturing and the process of manufacturing strategy development. An in-depth case from a UK company illustrates the evolving forms of manufacturing strategy development processes.
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This article describes the use of evolutionary methods to generate ambiguous images---images that the brain or a computer may interpret in multiple ways. Object detectors often falsely identify the presence of objects in these images, even when they are not visible to human observers.
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Background. The secondary structure of folded RNA sequences is a good model to map phenotype onto genotype, as represented by the RNA sequence. Computational studies of the evolution of ensembles of RNA molecules towards target secondary structures yield valuable clues to the mechanisms behind adaptation of complex populations. The relationship between the space of sequences and structures, the organization of RNA ensembles at mutation-selection equilibrium, the time of adaptation as a function of the population parameters, the presence of collective effects in quasispecies, or the optimal mutation rates to promote adaptation all are issues that can be explored within this framework. Results. We investigate the effect of microscopic mutations on the phenotype of RNA molecules during their in silico evolution and adaptation. We calculate the distribution of the effects of mutations on fitness, the relative fractions of beneficial and deleterious mutations and the corresponding selection coefficients for populations evolving under different mutation rates. Three different situations are explored: the mutation-selection equilibrium (optimized population) in three different fitness landscapes, the dynamics during adaptation towards a goal structure (adapting population), and the behavior under periodic population bottlenecks (perturbed population). Conclusions. The ratio between the number of beneficial and deleterious mutations experienced by a population of RNA sequences increases with the value of the mutation rate µ at which evolution proceeds. In contrast, the selective value of mutations remains almost constant, independent of µ, indicating that adaptation occurs through an increase in the amount of beneficial mutations, with little variations in the average effect they have on fitness. Statistical analyses of the distribution of fitness effects reveal that small effects, either beneficial or deleterious, are well described by a Pareto distribution. These results are robust under changes in the fitness landscape, remarkably when, in addition to selecting a target secondary structure, specific subsequences or low-energy folds are required. A population perturbed by bottlenecks behaves similarly to an adapting population, struggling to return to the optimized state. Whether it can survive in the long run or whether it goes extinct depends critically on the length of the time interval between bottlenecks. © 2010 Stich et al; licensee BioMed Central Ltd.