Abstract The objective was to evaluate the effect of different levels potassium fertilization on initial growth forage cactus (Nopalea cochenillifera Salm Dyck) clones. experiment lasted six months, arranged in a randomized block design, 5 x 2 factorial scheme, with five (0, 250, 500, 750, and 1,000 kg K2O ha-1) two clones (Little Sweet Giant Sweet), four replicates. One cladode planted per pot...

The film growth of the conjugated organic molecule rubicene on silicon dioxide was studied in detail. Since no structural data of the condensed material were available, we first produced high quality single crystals from solution and determined the crystal structure. This high purity material was used to prepare ultrathin films under ultrahigh vacuum conditions, by physical vapor deposition. Th...

Due to their extremely high genetic diversity, which is a direct consequence of high mutation rates, RNA viruses are often described as molecular quasispecies. According to this theory, RNA virus populations cannot be understood in terms of individual viral clones, as they are clouds of interconnected mutants, but this prediction has not yet been demonstrated experimentally. The goal of this st...

Dust grain growth and settling time inside initial gaseous giant protoplanets in the mass range 0.3 to 5 Jovian masses, formed by gravitational instability, have been investigated. We have determined the distribution of thermodynamic and physical variables inside the protoplanets solving the structure equations assuming their gas blobs to be fully convective and with this distribution we have c...