Phylogenetic networks are a useful way of displaying relationships between nucleotide or protein ... more Phylogenetic networks are a useful way of displaying relationships between nucleotide or protein sequences. They diverge from phylogenetic trees as networks present cycles, several possible evolutionary histories of the sequences analysed, while a tree presents a single evolutionary relationship. Networks are especially useful in studying markers with a high level of homoplasy (same mutation happening more than once during evolution) like the control region of mitochondrial DNA (mtDNA), where the researcher does not need to compromise with a single explanation for the evolution suggested by the data. However in many instances, trees are required. One case where this happens is in the founder analysis methodology that aims at estimating migration times of human populations along history and prehistory. Currently, the founder analysis methodology implicates the creation of networks, from where a probable tree will be extracted by hand by the researcher, a time-consuming process, prone to errors and to the ambiguous decisions of the researcher. In order to automate the founder analysis methodology an algorithm that extracts a single probable tree from a network in a fast, systematic way is presented here.
The stripping of amorphous hydrogenated carbon films (a-C:H) using an rf oxygen plasma has been m... more The stripping of amorphous hydrogenated carbon films (a-C:H) using an rf oxygen plasma has been monitored using the optical emission from electronically excited CO, H and O species in the visible region of the spectrum. The end point has been detected by monitoring the emission intensity of O reactive species (777.2 nm) and CO emission (483.5 nm) intensity of the
Abstract The authors studied the electric field behavior in the vicinity of a triple junction, co... more Abstract The authors studied the electric field behavior in the vicinity of a triple junction, composed by metal, vacuum and dielectric parts, using computational simulations. A bi-dimensional model was constructed using ANSYS MAXWELL to analyze the magnitude of the electric field as a function of the contact angles of the materials. The results showed that a field enhancement or reduction could occur in vacuum for certain contact angles. The influence of the dielectric permittivity was also investigated, and the conclusions showed that the maximum electric field enhancement is proportional to the dielectric permittivity.
Phylogenetic networks are a useful way of displaying relationships between nucleotide or protein ... more Phylogenetic networks are a useful way of displaying relationships between nucleotide or protein sequences. They diverge from phylogenetic trees as networks present cycles, several possible evolutionary histories of the sequences analysed, while a tree presents a single evolutionary relationship. Networks are especially useful in studying markers with a high level of homoplasy (same mutation happening more than once during evolution) like the control region of mitochondrial DNA (mtDNA), where the researcher does not need to compromise with a single explanation for the evolution suggested by the data. However in many instances, trees are required. One case where this happens is in the founder analysis methodology that aims at estimating migration times of human populations along history and prehistory. Currently, the founder analysis methodology implicates the creation of networks, from where a probable tree will be extracted by hand by the researcher, a time-consuming process, prone to errors and to the ambiguous decisions of the researcher. In order to automate the founder analysis methodology an algorithm that extracts a single probable tree from a network in a fast, systematic way is presented here.
The stripping of amorphous hydrogenated carbon films (a-C:H) using an rf oxygen plasma has been m... more The stripping of amorphous hydrogenated carbon films (a-C:H) using an rf oxygen plasma has been monitored using the optical emission from electronically excited CO, H and O species in the visible region of the spectrum. The end point has been detected by monitoring the emission intensity of O reactive species (777.2 nm) and CO emission (483.5 nm) intensity of the
Abstract The authors studied the electric field behavior in the vicinity of a triple junction, co... more Abstract The authors studied the electric field behavior in the vicinity of a triple junction, composed by metal, vacuum and dielectric parts, using computational simulations. A bi-dimensional model was constructed using ANSYS MAXWELL to analyze the magnitude of the electric field as a function of the contact angles of the materials. The results showed that a field enhancement or reduction could occur in vacuum for certain contact angles. The influence of the dielectric permittivity was also investigated, and the conclusions showed that the maximum electric field enhancement is proportional to the dielectric permittivity.
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