Lotka-Volterra model with Allee effect: equilibria, coexistence and size scaling of maximum and minimum abundance.

The Lotka-Volterra competition model (LVCM) is a fundamental tool for ecology, widely used to represent complex communities. The Allee effect (AE) is a phenomenon in which there is a positive correlation between population density and fitness, at low population densities. However, the interplay between the LVCM and AE has been seldom analyzed in multispecies models.

Antihypertensive Activity of the Alkaloid Aspidocarpine in Normotensive Wistar Rats.

The alkaloid Aspidocarpine was isolated from the bark of Aspidosperma desmanthum. Its structure was elucidated by the spectral data of 1H and 13C-NMR (1D and 2D) and high-resolution mass spectrometry (HRESIMS). The antihypertensive activity was investigated by intravenous infusion in Wistar rats.

New hydroperoxycycloartane-complete chemical shifts assignment of C and H-and cytotoxicity evaluation of cycloartanes isolated from .

New cycloartane, 22-hydroxy-25-hydroperoxycycloart-23-en-3-one (), along with six known analogues () and three steroids (), were isolated from the leaves of . Structures were elucidated mainly on the basis of the analysis of 1D and 2D NMR (H and C) and HRESIMS spectroscopic data, involving comparison with data of the literature. The cytotoxic activities of and isolated compounds were also evaluated against human leukemia cell line Molt-4 (acute lymphoblastic) and exhibited good cytotoxic activity with IC values ranging from 10.

Chemical Compounds and Biologic Activities: A Review of Genus.

The genus P. Browne, which belongs to the Meliaceae family, has eighteen species. Trees of this genus are of economic interest due to wood quality, as well as being the focus of studies because of relevant biologic activities as in other Meliaceae species.