Publications by authors named "Liang-qun Li"

Novel auxiliary truncated unscented Kalman filtering (ATUKF) is proposed for bearings-only maneuvering target tracking in this paper. In the proposed algorithm, to deal with arbitrary changes in motion models, a modified prior probability density function (PDF) is derived based on some auxiliary target characteristics and current measurements. Then, the modified prior PDF is approximated as a Gaussian density by using the statistical linear regression (SLR) to estimate the mean and covariance.

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Objective: To investigate the prognostic significance of Follicular Lymphoma International Prognostic Index 2 (FLIPI2) in FL patients treated with rituximab maintenance.

Methods: A tatol of 140 newly diagnosed FL patients who received Rituximab plus cyclophosphamide, doxorubicin, vincristine and prednisone (R-CHOP) chemotherapy in our department were retrospectively analyzed from December 2002 to December 2014. Among 140 patients with FL 122 patients achieved response, from them 56 patients received R maintenance (RM) every 2 months for median 8 times (RM group) while the rest 66 patients did not receive further anti-lymphoma treatment (non-RM group).

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Tracking the target that maneuvers at a variable turn rate is a challenging problem. The traditional solution for this problem is the use of the switching multiple models technique, which includes several dynamic models with different turn rates for matching the motion mode of the target at each point in time. However, the actual motion mode of a target at any time may be different from all of the dynamic models, because these models are usually limited.

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Catalytic asymmetric formal synthesis of (-)-Triptophenolide and (+)-Triptolide have been achieved. Key reaction involves Palladium catalyzed asymmetric conjugate addition of aryl boronic acid to 3-methyl cyclohexe-1-none to form quaternary carbon. Claisen rearrangement and subsequent aldol reaction furnished trans-decaline key intermediate, which assured a formal total synthesis of (-)-Triptophenolide and (+)-Triptolide.

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High contents of curcusones A and B and trace amounts of spirocurcasone exist in the roots of Jatropha curcas. Here, a one-step semisynthesis method of spirocurcasone and pyracurcasone was built, not only resulted an increased yield of spirocurcasone but also produced pyracurcasone, which exhibited greater cytotoxicity compared to curcusones A and B. The plausible mechanism of the formation of pyracurcasone was proposed, and the proposed biogenetic origin for spirocurcasone by Taglialatela-Scafati was confirmed.

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Four new phragmalin limonoids (chukfuransins A-D) were isolated from the twigs and leaves of Chukrasia tabularis. Chukfuransins A (1) and B (2) feature a unique C-15/C-20 linkage proposed to be built by a biogenetic pathway involving Michael addition. Chukfuransins C (3) and D (4) feature the C-15/C-21 linkage.

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Previous analyses of the naphthomycin biosynthetic gene cluster and a comparison with known naphthomycin-type products from Streptomyces sp. CS have suggested that new products can be found from this strain. In this study, screening by LC-MS of Streptomyces sp.

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The strain T1BF was isolated from the old bast tissue of Taxus yunnanensis and determined to be a member of Talaromyces. The extracts from the solid fermentation of Talaromycessp. T1BF were purified and obtained three azaphilones, including a new one.

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