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In this article, an improved Gaussian distribution based quantum-behaved particle swarm optimization (IG-QPSO) algorithm is proposed to solve engineering shape design problems with multiple constraints. In this algorithm, the Gaussian distribution is employed to generate the sequence of random numbers in the QPSO algorithm. By decreasing the variance of the Gaussian distribution linearly, the algorithm is able not only to maintain its global search ability during the early search stages, but can also obtain gradually enhanced local search ability in the later search stages. Additionally, a weighted mean best position in the IG-QPSO is employed to achieve a good balance between local search and global search. The proposed algorithm and some other well-known PSO variants are tested on ten standard benchmark functions and six well-studied engineering shape design problems. Experimental results show that the IG-QPSO algorithm can optimize these problems effectively in terms of precision and robustness compared to its competitors. [ABSTRACT FROM AUTHOR]

Objective: Previous studies have shown conflicting results on the use of antiplatelet (AP) agent and its risk of symptomatic intracerebral hemorrhage (sICH) following thrombolysis for acute ischemic stroke. Our study was to explore the safety of intravenous (IV) thrombolysis in Chinese stroke patients who were on AP prior to stroke. Methods: Data were collected from the thrombolysis implementation and monitor of acute ischemic stroke in China (TIMS-China) registry. Symptomatic ICH defined per SITS-MOST (safe implementation of treatments in stroke-monitoring study), ECASS II (second European-Australasian acute stroke study), and NINDS (National Institute of Neurological Disorders and Stroke) criteria, 90-day functional outcome, and 7- day and 90-day mortalities were compared between the stroke patients who were on mono and dual AP therapy. Results: A total of 157 (14.2%) patients received at least one AP drug within 24 hours before thrombolysis. Patients with preexisting dual AP treatment had higher rate of sICH (14.3% (2/14) per SITS-MOST, 21.4% (3/14) per ECASS II definitions) than those on no AP treatment. No significant difference was found in the rate of sICH or 7-day or 90-day mortalities between the groups on aspirin (ASA) alone and on no AP treatment. Discussion: The risk of developing sICH is low when thrombolysis is given to patients who are on ASA alone. However, there is potential increased risk of sICH if a patient is on dual AP treatment. [ABSTRACT FROM AUTHOR]