Search results for "Artificial environment"
showing 3 items of 3 documents
S-34 and N-15 labelling to model S and N flux in plants and determine the different components of N and S use efficiency
2013
International audience; In order to highlight our understanding on ecosystems functioning and resource sharing/competition, either in artificial environment or agrosystems, according to changes in the climatic conditions, it is necessary to measure accurately element fluxes within plants. Stable isotopes allow tracking safely and accurately on a short time frame the behavior of elements in plants. After a short review devoted to isotopic studies of elemental flux within plants, we explain how a direct multiple labelling study might be conducted in a plant, so as to measure over short time nitrogen and sulfur acquisition, and assimilates arising from a labelled source.
Experiments on Concurrent Artificial Environment
2001
We show how the simulation of concurrent system is of interest for both behavioral studies and strategies of learning applied on prey-predator problems. In our case learning studies into unknown environment have been applied to mobile units by using genetic algorithms (GA). A set of trajectories, generated by GA, are able to build a description of the external scene driving a predators to a prey. Here, an example of prey-predator strategy,based on field of forces, is proposed. The evolution of the corespondent system can be formalized as an optimization problem and, for that purpose, GA can be use to give the right solution at this problem. This approach could be applied to the autonomous r…
Artificial environmental conditions can affect allozyme genetic structure of the marine gastropod Patella caerulea
2001
Samples of the Mediterranean limpet Patella caerulea collected from 10 sites were examined for genetic population structure. Six of the 20 identified enzymatic loci were polymorphic. The AAT* locus was polymorphic only in two samples from an artificial environment (TI2 and PE). The proportion of polymorphic loci ranged from 0.20 to 0.30, and the observed and expected mean heterozygosity varied between 0.098 and 0.076 and between 0.109 and 0.086, respectively. Mean Fis values were significantly positive in AAT*, ESTD*, PEPC-2*, and PEPD*, showing heterozygosity deficiency. In all, mean Fst value of 0.007 indicated high genetic homogeneity between the samples analyzed, whereas single-locus Fs…