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Three new anthraquinones, 1-methyl-2,4-dimethoxy-3-hydroxyanthraquinone (6), 1-methoxy-3-hydroxy-2-ethoxymethylanthraquinone (7), and 2-methyl-3-O-β-D-primeveroside (14), together with 15 known compounds, including seven anthraquinones, one iridoid glucoside, three phenolic compounds, three flavone glucosides, and one flavone, were isolated from Paederia scandens. The isolated compounds were elucidated by extensive spectroscopic methods. To the best of our knowledge, six known anthraquinones (1, 2, 5, 9, 10, and 13) and two known phenolic acids (4, 11) were isolated from this plant for the first time.

We consider the problem of sequential, blind source separation in some specific order from a mixture of sub- and sup-Gaussian sources. Three methods of separation are developed, specifically, kurtosis maximization using (a) particle swarm optimization, (b) differential evolution, and (c) artificial bee colony algorithm, all of which produce the separation in decreasing order of the absolute kurtosis based on the maximization of the kurtosis cost function. The validity of the methods was confirmed through simulation. Moreover, compared with other conventional methods, the proposed method separated the various sources with greater accuracy. Finally, we performed a real-world experiment to separate electroencephalogram (EEG) signals from a super-determined mixture with Gaussian noise. Whereas the conventional methods separate simultaneously EEG signals of interest along with noise, the result of this example shows the proposed methods recover from the outset solely those EEG signals of interest. This feature will be of benefit in many practical applications.