Abstract We modeled biological growth using a random differential equation (RDE), where the initial condition is variable, and rate suitable stochastic process. These assumptions let us obtain model that represents well process observed in nature, only few individuals of population reach maximal size species, curve for every individual behaves randomly. Since we assumed assigned priori density,...

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We have utilized immunofluorescence techniques to look for synaptic vesicle antigens on the plasma membrane of resting and active nerve terminals. Rabbit antiserum was raised against purified cholinergic synaptic vesicles from the electric organ of Narcine brasiliensis, a marine electric ray. Antibodies to synaptic vesicles were shown to bind selectively to nerve terminals in cryostat sections ...

Narcine entemedor and Rhinoptera steindachneri are 2 viviparous batoid species of commercial importance on the Pacific coast Mexico. However, no adequate management plan has been set forth for either them to ensure sustainable use. The aims this study were assess reproductive potential rate population increase (rʹ) both species, as well contrasting their strategies, infer how susceptible they f...