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51.
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Ginés D. Guerrero José M. Cecilia Antonio Llanes José M. García Martyn Amos Manuel Ujaldón 《The Journal of supercomputing》2014,69(1):318-329
The rapidly growing field of nature-inspired computing concerns the development and application of algorithms and methods based on biological or physical principles. This approach is particularly compelling for practitioners in high-performance computing, as natural algorithms are often inherently parallel in nature (for example, they may be based on a “swarm”-like model that uses a population of agents to optimize a function). Coupled with rising interest in nature-based algorithms is the growth in heterogenous computing; systems that use more than one kind of processor. We are therefore interested in the performance characteristics of nature-inspired algorithms on a number of different platforms. To this end, we present a new OpenCL-based implementation of the Ant Colony Optimization algorithm, and use it as the basis of extensive experimental tests. We benchmark the algorithm against existing implementations, on a wide variety of hardware platforms, and offer extensive analysis. This work provides rigorous foundations for future investigations of Ant Colony Optimization on high-performance platforms. 相似文献
53.
María Cecilia Cimolai Silvia Alvarez Christoph Bode Heiko Bugger 《International journal of molecular sciences》2015,16(8):17763-17778
Sepsis is the manifestation of the immune and inflammatory response to infection that may ultimately result in multi organ failure. Despite the therapeutic strategies that have been used up to now, sepsis and septic shock remain a leading cause of death in critically ill patients. Myocardial dysfunction is a well-described complication of severe sepsis, also referred to as septic cardiomyopathy, which may progress to right and left ventricular pump failure. Many substances and mechanisms seem to be involved in myocardial dysfunction in sepsis, including toxins, cytokines, nitric oxide, complement activation, apoptosis and energy metabolic derangements. Nevertheless, the precise underlying molecular mechanisms as well as their significance in the pathogenesis of septic cardiomyopathy remain incompletely understood. A well-investigated abnormality in septic cardiomyopathy is mitochondrial dysfunction, which likely contributes to cardiac dysfunction by causing myocardial energy depletion. A number of mechanisms have been proposed to cause mitochondrial dysfunction in septic cardiomyopathy, although it remains controversially discussed whether some mechanisms impair mitochondrial function or serve to restore mitochondrial function. The purpose of this review is to discuss mitochondrial mechanisms that may causally contribute to mitochondrial dysfunction and/or may represent adaptive responses to mitochondrial dysfunction in septic cardiomyopathy. 相似文献
54.
Andrea Carugati Walter Fernández Lapo Mola Cecilia Rossignoli 《Information Systems Journal》2018,28(1):6-47
On the basis of a four‐year exploratory study of a mandatory information systems implementation by an Italian, multibillion‐dollar dairy cooperative with 2200 members, this paper describes how key stakeholders engage in dynamic transformation processes that shape the technology, the users' practices and the organisation itself. In doing so, this study responds to calls for process‐oriented longitudinal explorations and suggests an alternative path of adoption in which the technology becomes the reification of a bi‐directional discourse about the transformation of practices for the entire network of organisations. In presenting this alternative path, this study unveils a five‐phase change process that both altered perceptions of the technology and its possibilities at the same time resolving tensions among the drivers and users of the mandated system. © 2016 John Wiley & Sons Ltd 相似文献
55.
Christopher R Fellin Steven M Adelmund Dylan G Karis Ryan T Shafranek Robert J Ono Cecilia G Martin Trevor G Johnston Cole A DeForest Alshakim Nelson 《Polymer International》2019,68(7):1238-1246
We describe the synthesis, characterization and direct‐write 3D printing of triblock copolymer hydrogels that have a tunable response to temperature and shear stress. In aqueous solutions, these polymers utilize the temperature‐dependent self‐association of poly(alkyl glycidyl ether) ‘A’ blocks and a central poly(ethylene oxide) segment to create a physically crosslinked three‐dimensional network. The temperature response of these hydrogels was dependent upon composition, chain length and concentration of the ‘A’ block in the copolymer. Rheological experiments confirmed the existence of sol–gel transitions and the shear‐thinning behavior of the hydrogels. The temperature‐ and shear‐responsive properties enabled direct‐write 3D printing of complex objects with high fidelity. Hydrogel cytocompatibility was also confirmed by incorporating HeLa cells into select hydrogels resulting in high viabilities over 24 h. The tunable temperature response and innate shear‐thinning properties of these hydrogels, coupled with encouraging cell viability results, present an attractive opportunity for additive manufacturing and tissue engineering applications. © 2018 Society of Chemical Industry 相似文献
56.
A. Quiroga María C. Añón María Cecilia Puppo 《Journal of the American Oil Chemists' Society》2010,87(5):507-514
This study investigated, with the aim of obtaining more flexible and hydrophobic proteins, the attachment of a low chain fatty acid, decanoic acid, to alkaline and acid soybean proteins; and the effect on their conformational and functional properties. The extent of esterification was high at acid pH and also increased with heating. Protein solubility decreased, mainly at the highest temperature (60 °C). Increasing levels of fatty acid formed a complex with a slightly more soluble protein with less surface hydrophobicity. Esterified proteins exhibited aggregation/dissociation and were stabilized by different protein subunits belonging to 7S and 11S globulins. Denaturation of these soybean protein fractions (7S and 11S) were also detected in these complexes. The highest level of fatty acids favored formation of a more ordered protein structure. 相似文献
57.
Sintorn IM Homman-Loudiyi M Söderberg-Nauclér C Borgefors G 《Computer methods and programs in biomedicine》2004,76(2):95-102
An automatic image analysis method for describing, segmenting, and classifying human cytomegalovirus capsids in transmission electron micrograph (TEM) images of host cell nuclei has been developed. Three stages of the capsid assembly process in the host cell nucleus have been investigated. Each class is described by a radial density profile, which is the average grey-level at each radial distance from the center. A template, constructed from the profile, is used to find possible capsid locations by correlation based matching. The matching results are further refined by size and distortion analysis of each possible capsid, resulting in a final segmentation and classification. 相似文献
58.
59.
Cecilia Tortajada 《国际水资源开发杂志》2000,16(1):73-87
Mexico is well ahead of many developed and developing countries in many ways, especially in terms of the numbers of water projects constructed, successful transfer of irrigation districts and development of informal markets for groundwater. However, the deterioration of the natural resources of the country, water resources being one of them, due to improper management is not improving the lifestyle of the vast majority of the population in any significant way. Accordingly, extensive modifications in the planning and management processes, including consideration of environmental and social factors and stakeholder participation, are urgently necessary for the water sector. This paper includes an analysis of the environmental impact statements of water projects in Mexico which are under the responsibility of the national water authority. It concludes that the unsatisfactory quality of the EIS of water projects in Mexico represents a serious limitation for developing any post-project evaluation or impact management. The institutional arrangements necessary for implementing the proposed measures are not defined, and the costs of implementing any recommendation are not properly budgeted for in the cost tables. Finally, not only should the reports be critically analysed, but also the whole process of their preparation and approval should be objectively and critically reviewed. This analysis should indicate clearly the shortcomings of the process, and then outline what steps could be taken to overcome them in order to ensure the sustainability of water projects in Mexico. The emphasis should be on producing a streamlined and implementable process . 相似文献
60.