EXMOTIF is a useful and efficient tool in discovering structured motifs, especially in DNA sequences.
Discovering structured motifs in a set of DNA sequences is a computationally hard problem that has been addressed by a number of authors using either a direct approach, or via the preliminary identification and successive combination of simple motifs.
Lewis Dartnell, an astrobiologist at the University of Westminster, says that if the newly discovered structures are indeed stromatolites, the authors have "struck gold" given that plate tectonics and metamorphism of rocks typically destroys such structures.
But while the authors say the shape of the newly discovered structures, together with clues from their chemical make-up and signs of layers within them, suggests that they were formed by microbes, not everyone is convinced.
"Although remnants of soft tissues have previously been discovered in rare, exceptionally preserved fossils, what is particularly exciting about our study is that we have discovered structures reminiscent of blood cells and collagen fibres in scrappy, poorly preserved fossils.
If the object of the survey is to delineate already discovered structures, the surveyor sets up a grid over the area and makes measurements at each station on the grid.
Our discovered structure-activity relationships (SARs) of these analogues may serve as an important clue for further optimizations.
Bräuchle suggests that the tracks are tube-shaped invaginations of the nuclear membrane, recently discovered structures never before known to ferry viruses.
This paper presents three newly discovered structures that include tufted microbial mat, biological soil crusts, and gas-escape features, in addition to three previously documented structures that include roll up features, sand cracks, and wrinkled features.
Researchers do not know if the newly discovered structure was used for this purpose.
