Terra

Preciado-Rangel, Pablo;Baca-Castillo, Gustavo A.;Tirado-Torres, Juan L.;Kohashi-Shibata, Josué;Tijerina-Chávez, Leonardo;Martínez-Garza, Ángel Presión osmótica de la solución nutritiva y la producción de plántulas de melón TERRA Latinoamericana, Vol. 21, Núm. 4, octubre-...

Dal tempo della morte di Leonardo fino ad oggi non si sono esauriti i tentativi di identificare la donna ritratta nella tavola dipinta conosciuta col nome di Gioconda o Monna Lisa o, più recentemente, di individuare i luoghi ripresi nel paesaggio alle sue spalle. E' davvero solo un problema di identificazione il 'mistero' della Gioconda o c'è qualcosa di più? Questo saggio affronta l'ipotesi che il dipinto di Leonardo non sia un vero e proprio ritratto ma una rappresentazione allegorica. Di una persona che Leonardo amava appassionatamente più di ogni altra al Mondo: la Natura.

Mediante el uso de técnicas de programación lineal se desarrolló un modelo de optimización de recursos hídricos para el distrito de riego 005, localizado enDelicias, Chihuahua,México. Elmodelo planteado permitió estimar la superficie de riego y el patrón de cultivos óptimo para incrementar los beneficios netos de los productores. Se analizaron cuatro escenarios posibles, tomando en cuenta la disponibilidad de volúmenes clave en las fuentes de abastecimiento de agua, así como dos eficiencias de conducción de la red de canales. Los resultados indicaron que la superficie sembrada en el distrito fue de 70 459 ha. La superficie estimada por el modelo fue menor de 9643 ha con respecto a la superficie regable actualmente; por lo cual se concluye que es conveniente establecer estrategias para que, en situaciones próximas, la superficie excedente sea desincorporada del distrito de riego, o bien, reducir la concesión de agua con la finalidad de lograr la sustentabilidad de los módulos.

Cheko, a small lake located in Siberia close to the epicentre of the 1908 Tunguska explosion, might fill a crater left by the impact of a fragment of a Cosmic Body. Sediment cores from the lake’s bottom were studied to support or reject this hypothesis. A 175-cm long core, collected near the center of the lake, consists of an upper ∼1 m thick sequence of lacustrine deposits overlaying coarser chaotic material. 210Pb and 137Cs indicate that the transition from lower to upper sequence occurred close to the time of the Tunguska Event. Pollen analysis reveals that remains of aquatic plants are abundant in the top post-1908 sequence, but are absent in the lower pre-1908 portion of the core. These results, including organic C, N and δ13C data, suggest that Lake Cheko formed at the time of the Tunguska Event.

The present work aims to illustrate, through a mythocritical approach, how the product of Lucian Blaga’s lyrical mythopoiesis, specifically the moon named “zeul” ("god") in «Cântecul spicelor» («The Song of the Wheat Ears», published posthumously in 1970), may be classified as the divinity-type known as the “Fecundator” in the history of religions. In the first part, after identifying the waxing crescent with the phallus – the symbol par excellence of the Masculine principle –, a “lunar” Fecundator is associated with Blaga’s astral god. From his place in the sky this god has a “spécialisation génésico-taurine”, and the power to inseminate the earth through his spermatic rain, since he is endowed with a “phallic” horn. Moreover, the ophidian hypostasis of the moon, which further justifies its virility, is presented: the serpent – in the same way as the taurine horn – is isotopic with the phallic waxing crescent. The second part of the article describes how the Blagian moon awakens, in the virginal ears – symbolizing the daughters and hypostases of the Goddess Earth –, a fervent “dor” ("desire") . However, at the same time the Blagian moon produces a tremor of death due to its “seceră” form, since the sickle is the tool that severs the plant’s life, while also promising its future rebirth. Finally, this work underlines the key-role played by the fire element as an instrument of Eros: it is evoked in “în arderea vântului”, a syntagm epitomizing the ears’ hope for a kind of death which would allow them to ascend to the sky and rejoin the moon-god. Thus, the transience that the vegetation drama imposes upon them would disappear, and the moon’s harvesting would fill the chasm separating the sub-lunar world, which is the realm of eternal becoming, from the sempiternal dominion of the lunar world, i.e. the celestial realm.