In mammalian eggs, glycogen may well play an important role as an energy source during cleavage. Although the presence of glycogen in rat and rabbit eggs and the fluctuation of its concentration during development have been reported (ISHIDA 1954, 1963), histochemical demonstration of enzymes related to glycogen metabolism has not yet been published. Studies of glycogen metabolism are generally ...

Knowledge of altitude, attitude and motion is essential for an Unmanned Aerial Vehicle during critical maneuvers such as landing and take-off. In this paper we present a hybrid stereoscopic rig composed of a fisheye and a perspective camera for vision-based navigation. In contrast to classical stereoscopic systems based on feature matching, we propose methods which avoid matching between hybrid...

The "axonal flow" theory holds that the nerve cell body is continuously forming new cytoplasm which enters the axon and travels along its length. This theory was formulated by Weiss and collaborators (Weiss and Hiscoe, '48) to account for the accumulation of material in front of a nerve constriction and for the high concentration of enzymes appearing in the proximal stump of a sectioned nerve (...

Resumen. Objetivo/contexto: En la segunda mitad del siglo xix en Francia, revistas como Le Tour du Monde y las novelas ilustradas impulsaron ciencias geográficas propaganda educativa política de Tercera República sus intereses económicos a partir los relatos exploración viajeros franceses. Este artículo presenta un análisis imaginarios geográficos Orinoco estudio caso publicaciones viajes Jules...

When the railway appeared as a new means of transportation in the first half of the 19th century, its top speed of 30 to 40 km/h was considered dangerous. In Germany, where Adler transported two barrels of beer between Nuremberg and Fürth in 1835 as the first German rail freight, physicians warned people against such perilous adventures and farmers were worried that their cows grazing alongside...