33 resultados para Iterative Closest Point (ICP) Algorithm
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Contém resumo
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AuNPs are versatile systems used for different biomedical application including imaging, drug and gene delivery. These systems support the intracellular transport of active molecules, a step that is considered one of the crucial problems in drug delivery. Nevertheless, in order to design optimal multifunctional AuNPs for specific and efficient nanomedicine applications, the mechanism by which AuNPs interact with living cells must be fully understand. The main goal of this work consisted in the assessment of the cellular uptake mechanism of 14 nm spherical AuNPs by A549 cells, through fluorescent spectroscopy and microscopy, in combination with quantitative analysis by ICP-MS. TAMRA labeled AuNPs were characterized by UV-visible and fluorescent spectroscopy and the final hydrodynamic diameter of 22.5 ± 0.33 nm was obtained by DLS. Regarding the cellular uptake studies, the AuNPs presented a fast cellular uptake kinetics reaching a saturation point after 6 hours of incubation in A549 cells. Further investigation concerning the internalization mechanism of this AuNPs was evaluated using specific inhibitors for different endocytic pathways. Optimal inhibition was achieved using chlorpromazine, inhibitor of clathrin-mediated endocytosis, resulting in a 23.5 % inhibition of AuNPs after 1 hour of incubation. This preliminary result obtained by fluorescent spectroscopy suggests that these AuNPs were predominantly uptake by clathrin-mediated endocytosis, meaning that other endocytic pathways must be involved in the cellular uptake of this AuNPs. In what cell viability is concern, the prepared AuNPs and the endocytic inhibitors revealed no significant effect on the cell viability in A549 cell line.
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Ship tracking systems allow Maritime Organizations that are concerned with the Safety at Sea to obtain information on the current location and route of merchant vessels. Thanks to Space technology in recent years the geographical coverage of the ship tracking platforms has increased significantly, from radar based near-shore traffic monitoring towards a worldwide picture of the maritime traffic situation. The long-range tracking systems currently in operations allow the storage of ship position data over many years: a valuable source of knowledge about the shipping routes between different ocean regions. The outcome of this Master project is a software prototype for the estimation of the most operated shipping route between any two geographical locations. The analysis is based on the historical ship positions acquired with long-range tracking systems. The proposed approach makes use of a Genetic Algorithm applied on a training set of relevant ship positions extracted from the long-term storage tracking database of the European Maritime Safety Agency (EMSA). The analysis of some representative shipping routes is presented and the quality of the results and their operational applications are assessed by a Maritime Safety expert.