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1.
Philos Trans A Math Phys Eng Sci ; 368(1924): 3551-65, 2010 Aug 13.
Artículo en Inglés | MEDLINE | ID: mdl-20603367

RESUMEN

Emerging technologies offer new solutions to the construction industry, improving processes, enabling automation and effective decision-making mechanisms and changing current ways of work. Previous research has tended to consider a direct causal relationship between the emerging and prospective technologies and the future of construction. However, the future of construction will be influenced not only by the developments in the information technology (IT) industry, but also by other technological changes. Societal, economic, environmental and political factors will shape the future, together with emerging technologies. This paper presents a scenario-planning exercise that aimed to identify possible futures that the construction industry might face. In order to achieve the aims of the research, a literature review was carried out on scenario planning and future studies related to construction and construction IT, which was followed by a mini survey and two prospective workshops as part of the La Prospective scenario-planning approach. In a future study, it is important to understand the forces, issues and trends in order to inform and enable further thinking and action towards achieving a preferred future state whilst being prepared for what might be round the corner. Therefore, the paper first investigates the driving forces of change, main trends, issues and factors that might shape the future, focusing on factors related to society, technology, environment, economy and politics. Secondly, four future scenarios that were developed keeping these factors in mind are presented. The scenarios start from a global view and present the images of the future world in year 2030. They later focus on the construction industry, imagining how it will be shaped by the future world and trying to visualize the information and communication technology implications for construction. Finally, a preferred future scenario for 2030 is introduced based on the principle that the future can be influenced if we know what we want it to be. Focusing mainly on the IT vision, the paper concludes with recommendations in the areas related to innovation, communication and collaboration, education and training, process improvement, interoperability, user-centred IT and sustainability, in order to reach the desired state determined by the vision.

2.
J Chemother ; 21(2): 153-8, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19423467

RESUMEN

Escherichia coli is the most common causative agent of recurrent, uncomplicated urinary tract infections. Triplex pCR and the disc diffusion method were used to determine and correlate among the phylogenetic group, virulence determinants and antimicrobial resistance in 100 uropathogens. Group B2 represented 58% of the tested isolates with no isolates belonging to group B1. Isolates with the highest percentage of susceptibility to all antimicrobial agents used were within the B2 phylogenetic groups. 38% of the tested population were resistant to trimethoprim/sulfamethoxazole, 29% to ciprofloxacin and only 8% to nitrofurantoin. The majority of the isolates resistant to trimethoprim/sulfamethoxazole were from group B2 (52.7%), with 45% being positive to the three tested virulence determinants (efu, fbp and picU). These findings suggest that although virulence and antimicrobial resistance are mutually exclusive in Escherichia coli clinical isolates, the relationship between virulence and resistance to antimicrobial agents can vary according to the particular resistance phenotype.


Asunto(s)
Antiinfecciosos Urinarios/farmacología , Farmacorresistencia Bacteriana/genética , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Factores de Virulencia/genética , Humanos , Líbano , Pruebas de Sensibilidad Microbiana , Filogenia , Reacción en Cadena de la Polimerasa , Virulencia/genética
3.
Sci Total Environ ; 393(2-3): 385-93, 2008 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-18262597

RESUMEN

Municipal solid waste incinerator bottom ash (MSWI BA) can be used in road construction where it can become exposed to microbial attack, as it can be used as a source of oligoelements by bacteria. The extent of microbial colonization of the bottom ash and the intensity of microbial processes can impact the rate of leaching of potentially toxic elements. As a consequence, our objective was to highlight the mutual interactions between MSWI bottom ash and Pseudomonas aeruginosa, a common bacteria found in the environment. Experiments were carried out for 133 days at 25 degrees C using a modified soxhlet's device and a culture medium, in a closed, unstirred system with weekly renewal of the aqueous phase. The solid products of the experiments were studied using a laser confocal microscopy, which showed that biofilms formed on mineral surfaces, possibly protecting them from leaching. Our results show that the total mass loss after 133 days is systematically higher in abiotic medium than in the biotic one in proportions going from 31 to 53% depending on element. Ca and Sr show that rates in biotic medium was approximately 19% slower than in abiotic medium during the first few weeks. However, in the longer term, both rates decreased to reach similar end values after 15 weeks. By taking into account the quantities of each tracer trapped in the layers we calculate an absolute alteration rate of MSWI BA in the biotic medium (531 microg m(-2) d(-1)) and in the abiotic one (756 microg m(-2) d(-1)).


Asunto(s)
Incineración , Residuos Industriales , Metales Pesados/metabolismo , Pseudomonas aeruginosa/metabolismo
4.
J Hazard Mater ; 136(3): 889-95, 2006 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-16507331

RESUMEN

A basaltic glass and a vitrified bottom ash were incubated at 25 degrees C in a growth medium (based on casaminoacids) inoculated with Pseudomonas aeruginosa. Bacterial growth and mineral concentrations in different compartments (bacterial cells, growth medium and biofilm) were monitored in short-term (3 days), and long-term experiments involving repeated renewals of the culture medium during 174 days. In short-term experiments, while the concentration of iron increased in the presence of bacteria, a decrease in Ni and Zn was observed in the growth medium compared to the sterile condition. During long-term experiments, such differences gradually decreased and disappeared after 78 days. On the contrary, iron concentration remained higher in the biotic condition compared to the sterile one. Bacterial growth resulted within a few days in the formation of a biofilm, which lead to the cementation of the altered glass grains. Most of the constituents of the glass (Si, Mg, Fe, Ti, Ba, Co, Zn, Cu, Ni and Cr) were found in the biofilm, while the chemical composition of the bacterial cells was very different.


Asunto(s)
Biopelículas , Vidrio/química , Metales/química , Pseudomonas aeruginosa/metabolismo , Adsorción , Medios de Cultivo , Concentración de Iones de Hidrógeno , Residuos Industriales/análisis , Microscopía Electrónica , Microscopía Electrónica de Rastreo , Tetróxido de Osmio/química , Factores de Tiempo
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