Publications by authors named "Yu-Qiang Wu"

Numerous flavonoid Diels-Alder-type natural products have been isolated and received great attention from the synthetic community. Herein, we reported a catalytic strategy for an asymmetric Diels-Alder reaction of 2'-hydroxychalcone with a range of diene substrates using a chiral ligand-boron Lewis acid complex. This method enables the convenient synthesis of a wide range of cyclohexene skeletons in excellent yields with moderate to good enantioselectivities, which is critical to prepare natural product congeners for further biological studies.

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This article concentrates on an adaptive backstepping control design of time-delay strict-feedback uncertain nonlinear systems subject to full state constraints. The tan-type barrier Lyapunov functions (tBLFs) and Lyapunov-Krasovskii function are united together, which successfully get over the difficulties of system design in which the first function is involved to ensure full state constraints satisfaction and the second is established to eliminate the effect of delayed states. By employing a new control scheme, asymptotic tracking performance is arrived, and all the states remain in the desirable regions for all the system running time.

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This paper addresses the problem of output feedback stabilization for a class of time-delay nonholonomic systems. One distinct characteristic or difficulty of this paper is that time-delay exists in polynomial nonlinear growing conditions. Based on input-state-scaling technique, homogeneous domination approach and Lyapunov-Krasovskii theorem, a new output feedback control law which guarantees all the system states converge to the origin is designed.

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Objectives: The National Institutes of Health Chronic Prostatitis Symptom Index (NIH-CPSI) was used to determine the chronic prostatitis syndrome in young men (from 20 to 48 years old) of clinical validity.

Methods: 227 patients with chronic prostatitis syndrome (CPS)/chronic pelvic pain syndrome and 32 patients with BPH were randomized to study using NIH-CPSI.

Results: 1.

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