Integrate and fire processes are fundamental mechanisms causing excitable and oscillatory behavior. Van der Pol [Philos. Mag. (7) 2 (11) (1926) 978] studied oscillations caused by these processes, which he called,relaxation oscillations' and pointed out their relevance, not only to…

The Upper Cenozoic flora of the Pie de Vaca Formation, Puebla, Mexico, is yielding important elements that contribute to a more complete knowledge of the Tertiary floras of southern latitudes of North America. Among the most abundant plant organs in…

El presente Seminario de Titulación es básicamente un trabajo de investigación y análisis sobre la Ciberinfraestructura disponible en la Web para el manejo y recuperación de literatura especializada en Ciencias Biomédicas, el cual incluye la descripción y una clasificación con…

The hydrological characteristics of the Peninsula of Yucatan have given cause for the systems training limnological very particular, that include exposed and underground waters of origin carstic. The aquatic fauna of the cenotes and caves yucatecos has been studied from…

The Gulf 0f Mexico constitutes a natural resource of immense ecological and economic importance foe Mexico and the World (Vidal, el al., 1997). Our capacity to exploitit rationallydepends on our knowledge of its nature, fundamentally of its circulation system, amongst…

Palm leaves are an important resource for family households. The effect of harvest on leaf production, growth and fecundity of wild individual palm trees has been studied, but little is known about palm harvest in agro-forestry systems. In the Maya…

While biologists have been aware of the existence of native Mexican trouts for over a century, they have received little study. The few early studies that did muchmore than mention their existence began in the 1930s and continued into the…

Knowledge of the population dynamics of tropical trees has expanded considerably in the past 20 years. An important observation deriving from these investigations is the confirmation that population behaviour varies both in time and space. A tool recently developed to…

Through the use of line transects on boats, contributions to the knowledge of vaquita Phocoena sinus distribution were made. Sightings made confirm the presence of vaquita near Rocas Consag. Stranded individuals were collected for anatomical, morphometric, and age estimation studies.…

The mammalian fauna of the State of Mexico is included in 20 families 61 genera and 103 species. Here we make a retrospective analysis and present an updated taxonomic checklist of the mammals of the state. In the list, the…