102 resultados para Local and Global Well-Posedness


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This paper reviews a number of huge challenges to ethical leadership in the twenty-first century and concludes that the need for global ethical leadership is not merely a desirable option, but rather – and quite literally – a matter of survival. The crises of the recent past reveal huge, and in some cases criminal, failures of both ethics and leadership in finance, business and government. We posit that mainstream economic theory’s construct of ‘homo economicus’ and its faith in the ‘invisible hand’ of the market constitute deeply flawed foundations upon which alone policy may be built and, farthermore, that these problematic foundations exert substantial shaping power over the institutional and discursive landscapes in which international business is transacted. Analogously, we argue that dominant approaches to business ethics and corporate social responsibility are, if not incorrect, at least in need of revisiting in terms of questioning their basic assumptions. Instead of the smugness of Western (especially Anglo-American) attitudes towards other ways of thinking, valuing and organising, it appears clear that openness, cooperation and co-creation between the developed and developing worlds is a basic prerequisite for dealing with the global challenges facing not just leaders, but humanity as a whole. This objective of stimulating discussion between dominant and marginal voices has guided our selection of papers for this Special Issue. We have thus included not only representatives of research from within the parameters of mainstream business ethics, IB or leadership scholarship, but also innovative contributions from fields such as military history, information technology, regulation, spirituality and sociology.

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Ant-like agents forage between two points. These agents' probabilistic movements are based on the use of two pheromones; one marking trails towards the goal and another marking trails back to the starting point. Path selection decisions are influenced by the relative levels of attractive and repulsive pheromone in each agent's local environment. Our work in [5] evaluates three pheromone perception strategies, investigating path formation speed, quality, directionality, robustness and adaptability under different parameter settings(degree of randomness, pheromone evaporation rate and pheromone diffusion rate). We re-evaluate two of these strategies in terms of the amount of information they provide using Shannon's formulation [3, 4, 8, 9, 12, 14, 15, 16, 17]. We determine information as the difference between uncertainty before and after path selection decisions. Our focus in this paper is on investigating relationships between the emergence of the shortest path and the amount of stigmergic information that exists in the form of pheromone. Agents are deployed centrally and emergence measures are determined using the worst, reference and best cases observed in [5]. Additionally, the amount of local and global information that is available to agents in each movement step is evaluated. Furthermore, Pearson's correlation coefficients between measures of emergence and the amount of information are calculated. The significance of these correlation coefficients is tested using a 2 tailed test at 1% level of significance. Consequently the relationship between the amount of information and emergent behaviour is established. Significant relationships between information and the emergence of the shortest path exist when strong emergent behaviour is present.

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The Saccharomyces cerevisiae WD-40 repeat protein Swd2p associates with two functionally distinct multiprotein complexes: the cleavage and polyadenylation factor (CPF) that is involved in pre-mRNA and snoRNA 3′ end formation and the SET1 complex (SET1C) that methylates histone 3 lysine 4. Based on bioinformatic analysis we predict a seven-bladed β-propeller structure for Swd2p proteins. Northern, transcriptional run-on and in vitro 3′ end cleavage analyses suggest that temperature sensitive swd2 strains were defective in 3′ end formation of specific mRNAs and snoRNAs. Protein–protein interaction studies support a role for Swd2p in the assembly of 3′ end formation complexes. Furthermore, histone 3 lysine 4 di-and tri-methylation were adversely affected and telomeres were shortened in swd2 mutants. Underaccumulation of the Set1p methyltransferase accounts for the observed loss of SET1C activity and suggests a requirement for Swd2p for the stability or assembly of this complex. We also provide evidence that the roles of Swd2p as component of CPF and SET1C are functionally independent. Taken together, our results establish a dual requirement for Swd2p in 3′ end formation and histone tail modification.

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Despite the increased recognition of the potential use of online technologies to deliver flexible and student-centered learning environments in higher education, there are numerous critiques that its usage does not transform the daily practices of teaching and learning. This paper draws on some of the findings from three case studies that explored the manifestation of blended learning pedagogies (BLP). Six academics teaching at three different higher education contexts at two different countries, namely Australia and Malaysia were interviewed. The study aimed to interrogate the different manifestation of BLP at the different contexts of higher education, highlighting the complex interplay between the users (academics), technology and the specific socio-cultural contexts. Focusing on the academic identities that are shaped and reshaped within its socio-cultural context, this study demonstrated the complexity and fluidity of the manifestation of the different varieties of BLP. It contributes to further understanding the ways in which online technologies are used in teaching and learning within context of global knowledge economy that emphasizes flexibility and active co-production of knowledge.

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In this work we present a new image thresholding algorithm for the segmentation of MRI brain images into two classes: gray matter and white matter. The proposed algorithm is based on the concept of incomparability proposed by Fodor and Roubens for fuzzy preference relations. We test our algorithm for local and global segmentation of brain images. We proof that global segmentation performs better results than local segmentation and improves the results obtained by other thresholding algorithm.

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Background: Current approaches of predicting protein functions from a protein-protein interaction (PPI) dataset are based on an assumption that the available functions of the proteins (a.k.a. annotated proteins) will determine the functions of the proteins whose functions are unknown yet at the moment (a.k.a. un-annotated proteins). Therefore, the protein function prediction is a mono-directed and one-off procedure, i.e. from annotated proteins to un-annotated proteins. However, the interactions between proteins are mutual rather than static and mono-directed, although functions of some proteins are unknown for some reasons at present. That means when we use the similarity-based approach to predict functions of un-annotated proteins, the un-annotated proteins, once their functions are predicted, will affect the similarities between proteins, which in turn will affect the prediction results. In other words, the function prediction is a dynamic and mutual procedure. This dynamic feature of protein interactions, however, was not considered in the existing prediction algorithms.

Results: In this paper, we propose a new prediction approach that predicts protein functions iteratively. This iterative approach incorporates the dynamic and mutual features of PPI interactions, as well as the local and global semantic influence of protein functions, into the prediction. To guarantee predicting functions iteratively, we propose a new protein similarity from protein functions. We adapt new evaluation metrics to evaluate the prediction quality of our algorithm and other similar algorithms. Experiments on real PPI datasets were conducted to evaluate the effectiveness of the proposed approach in predicting unknown protein functions.

Conclusions:
The iterative approach is more likely to reflect the real biological nature between proteins when predicting functions. A proper definition of protein similarity from protein functions is the key to predicting functions iteratively. The evaluation results demonstrated that in most cases, the iterative approach outperformed non-iterative ones with higher prediction quality in terms of prediction precision, recall and F-value.

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A wide variety of stressors elicit Fos expression in the medial prefrontal cortex (mPFC). No direct attempts, however, have been made to determine the role of the inputs that drive this response. We examined the effects of lesions of mPFC catecholamine terminals on local expression of Fos after exposure to air puff, a stimulus that in the rat acts as an acute psychological stressor. We also examined the effects of these lesions on Fos expression in a variety of subcortical neuronal populations implicated in the control of adrenocortical activation, one classic hallmark of the stress response. Lesions of the mPFC that were restricted to dopaminergic terminals significantly reduced numbers of Fos-immunoreactive (Fos-IR) cells seen in the mPFC after air puff, but had no significant effect on stress-induced Fos expression in the subcortical structures examined. Lesions of the mPFC that affected both dopaminergic and noradrenergic terminals also reduced numbers of Fos-IR cells observed in the mPFC after air puff. Additionally, these lesions resulted in a significant reduction in stress-induced Fos-IR in the ventral bed nucleus of the stria terminalis. These results demonstrate a role for catecholaminergic inputs to the mPFC, in the generation of both local and subcortical responses to psychological stress.

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Background: Both male and female pigeons have the ability to produce a nutrient solution in their crop for the nourishment of their young. The production of the nutrient solution has been likened to lactation in mammals, and hence the product has been called pigeon ‘milk’. It has been shown that pigeon ‘milk’ is essential for growth and development of the pigeon squab, and without it they fail to thrive. Studies have investigated the nutritional value of pigeon ‘milk’ but very little else is known about what it is or how it is produced. This study aimed to gain insight into the process by studying gene expression in the ‘lactating’ crop.
Results: Macroscopic comparison of ‘lactating’ and non-’lactating’ crop reveals that the ‘lactating’ crop is enlarged and thickened with two very obvious lateral lobes that contain discrete rice-shaped pellets of pigeon ‘milk’. This was characterised histologically by an increase in the number and depth of rete pegs extending from the basal layer of the epithelium to the lamina propria, and extensive proliferation and folding of the germinal layer into the superficial epithelium. A global gene expression profile comparison between ‘lactating’ crop and non-’lactating’ crop showed that 542 genes are up-regulated in the ‘lactating’ crop, and 639 genes are down-regulated. Pathway analysis revealed that genes up-regulated in ‘lactating’ crop were involved in the proliferation of melanocytes, extracellular matrix-receptor interaction, the adherens junction and the wingless (wnt) signalling pathway. Gene ontology analysis showed that antioxidant response and microtubule transport were enriched in ‘lactating’ crop.
Conclusions: There is a hyperplastic response in the pigeon crop epithelium during ‘lactation’ that leads to localised cellular stress and expression of antioxidant protein-encoding genes. The differentiated, cornified cells that form the pigeon ‘milk’ are of keratinocyte lineage and contain triglycerides that are likely endocytosed as very low density lipoprotein (VLDL) and repackaged as triglyceride in vesicles that are transported intracellularly by microtubules. This mechanism is an interesting example of the evolution of a system with analogies to mammalian lactation, as pigeon ‘milk’ fulfils a similar function to mammalian milk, but is produced by a different mechanism.

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The existence of a positive relationship between spiritual engagement and well-being is currently based on weak correlational evidence, generally in Western contexts. This study advances understanding through a naturalist, longitudinal study of 226 people, including Malays, Chinese, and Indians, experiencing the Hindu Thaipusam festival in Malaysia. We measured the subjective well-being of people with varying levels of engagement—from nonobservance or simply observing the festival to extreme engagement. Each person was assessed 3 months before, 2 weeks before, 2 weeks after, and 4 months after the festival. We found that the subjective well-being of those with the most extreme level of engagement was permanently higher than other groups. The well-being of those with a strong, but less extreme engagement rose at the time of the festival and remained elevated. The findings are discussed in relation to homeostatic theory of well-being and the potential benefits of spiritual engagement.