Gerardo León

Learn More
Phyllodistomum inecoli n. sp. is described from the twospot livebearer, Heterandria bimaculata (Teleostei: Poeciliidae), collected in the Río La Antigua basin, Veracruz, Mexico. The new species is described and characterised by using a combination of morphology, scanning electron microscopy, and sequences of nuclear and mitochondrial genes. Diagnostic(More)
The taxonomic history and species composition of the genus Clinostomum has been unstable. Two species, Clinostomum complanatum Rudolphi, 1814 and Clinostomum marginatum Rudolphi, 1819, have been particularly problematic and its validity has been disputed for nearly 200 years. In this paper, we have made use of an integrative taxonomy approach, and we used,(More)
Heavy metals removal/recovery from industrial wastewater has become a prime concern for both economic and environmental reasons. This paper describes a comparative kinetic study of the removal/recovery of copper(II) from aqueous solutions by bulk liquid membrane using two types of coupled facilitated transport mechanisms and three carriers of different(More)
The presence of heavy metals in aqueous solutions above certain limits represents a serious threat to the environment due to their toxicity and non-degradability. Thus, the removal of these metals from contaminated waters has received increasing attention during recent decades. This paper describes the removal of Cu(II) from aqueous solutions by emulsion(More)
We provide a summary overview of the diversity of trematode parasites in freshwater fishes of the ‘New World’, i.e. the Americas, with emphasis on adult forms. The trematode fauna of three regions, South America, Middle America, and USA and Canada (North America north of Mexico), are considered separately. In total, 462 trematode species have been reported(More)
The systematic position of two genera of Macroderoididae McMullen, 1937, Perezitrema Baruš & Moravec, 1967 and Magnivitellinum Kloss, 1966 is reviewed based on a phylogenetic analysis of the interrelationships of 15 species of the family allocated into six genera, along with 44 species of plagiorchioid trematodes, using partial sequences of the 28S rRNA(More)
Caligus serratus Shiino, 1965 (Copepoda: Caligidae), a parasite on 11 fish species caught in Chamela Bay off the Pacific Coast of Mexico, is redescribed based on material found on Pacific agujon needlefish Tylosurus pacificus (Steindachner, 1876). Caligus serratus can be distinguished from its congeners by the combination of the following characters: i)(More)
  • Olmos, Jorge-Botana, G León, Escudero
  • 2013
This research has three main objectives: (1) following the procedure for interpreting LSA space dimensions (Hu, et al, 2005), we implement a change of basis, from the original canonical basis into a basis whose vectors are real terms; (2) we show that a simple change of basis alone is not enough for this purpose; and (3) we present Gram-Schmitdt(More)
 Engineers are involved in the implementation, application, operation, design and management of projects and processes, changing the type of work with the specific engineering field. The world in which engineers operates at the beginning of this century, is characterised by the diverse, profound and incessant changes occurring in technology, natural(More)
 Engineering can be considered as a broad discipline that embraces knowledge and training in science, mathematics, business and management, social science and computer technology. A wide range of skills can be defined as necessary to an actual engineer. Among them, technical knowledge skills and intellectual skills play a very important role. The teaching(More)