Three new chromones, pisonins A (1), B (2), and D (4), two new flavonoids, pisonivanone [(2S)-5,7,2'-trihydroxy-8-methylflavanone] (7) and pisonivanol [(2R,3R)-3,7-dihydroxy-5,6-dimethoxyflavanone] (8), one new isoflavonoid, pisonianone (5,7,2'-trihydroxy-6-methoxy-8-methylisoflavone) (9), and five compounds first isolated from nature, namely, pisonins C (3), E (5), and F (6), pisoniamide (10), and pisonolic acid (11), together with 18 known compounds have been isolated from the methanol extract of the combined stem and root of Pisonia aculeata. Among these isolates, 2, 7, 14, 16, and 19 exhibited antitubercular activities (MICs≤50.0 μg/mL) against Mycobacterium tuberculosis H37Rv in vitro.

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Palladium complexes supported with the mixed ligands carbodicarbene (CDC) and different phosphine ligands (PPh3, PTol3, and PCy3) were prepared, and their molecular structures were characterized. Examination of the structures of 2-PPh 3 and 2-PTol 3 with cis configuration discloses the existence of an unexpected π–π interaction between one phenyl group of the phosphine and the benzimidazole ring of a CDC. The palladium complex 2-PPh 3 is an active Suzuki–Miyaura catalyst with a wide scope of substrates containing various functional groups and steric demands. In contrast to electron-withdrawing aryl bromide, the yield of product for electron-rich substrates was improved by adding a catalytic amount of DMSO under aerobic conditions. The solution NMR and structural analysis has revealed that the intramolecular π–π interaction between CDC and phosphine ligands has a positive influence on the activity of the reaction, which is further supported by quantum chemical calculations.

This paper presents the algorithms used in a prototypical software system for automatic pronunciation assessment of Mandarin Chinese. The system uses forced alignment of HMM (Hidden Markov Models) to identify each syllable and the corresponding log probability for phoneme assessment, through a ranking-based confidence measure. The pitch vector of each syllable is then sent to a GMM (Gaussian Mixture Model) for tone recognition and assessment. We also compute the similarity of scores for intensity and rhythm between the target and test utterances. All four scores for phoneme, tone, intensity, and rhythm are parametric functions with certain free parameters. The overall scoring function was then formulated as a linear combination of these four scoring functions of phoneme, tone, intensity, and rhythm. Since there are both linear and nonlinear parameters involved in the overall scoring function, we employ the downhill Simplex search to fine-tune these parameters in order to approximate the scoring results obtained from a human expert. The experimental results demonstrate that the system can give consistent scores that are close to those of a human's subjective evaluation.