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The lack of data due to the high cost of experiments, limited knowledge of system structure, and coupling failure mechanism make it necessary to consider uncertainties when analyzing the reliability of complex systems. This paper provides a comprehensive work for system reliability analysis under consideration of mixed uncertainties. First, Bayesian networks (BNs) are used to model the structure of complex systems. Second, mixed uncertainties are described via a probability box and accurately quantified by the Bhattacharyya distance, which can synthetically represent the mean and variance of two data sets. Then, the importance of components with mixed uncertainties is defined and analyzed. Finally, a comprehensive sensitivity index is proposed for sensitivity analysis and epistemic uncertainty tracing of data sources based on the Bhattacharyya distance. This method is used to analyze the reliability of an auxiliary power supply system of a train and verifies the feasibility and accuracy of the proposed method. [ABSTRACT FROM AUTHOR]

On-line continuous sampling, ionic liquid-based dynamic microwave-assisted extraction high performance liquid chromatography has been developed and applied to the extraction of lipophilic constituents from root of Salvia miltiorrhiza Bunge. Several operating parameters were optimized by single-factor and Box- Behnken design experiments. The type and concentration of ionic liquids, power of microwave irradiation, flow rate of sample suspension, amount, and particle size of sample were investigated. The limits of detection for tanshin-one I, cryptotanshinone, and tanshinone IIA are 0.014, 0.009, and 0.009 mg/g, respectively. The RSDs of interday and intraday were lower than 2.02 and 2.16%, respectively. The recoveries for target analytes were in the range of 90.7-101.8%. The homogeneity of the suspension and stability of the analytes were investigated and the results were satisfactory. The proposed method was compared with the off-line ionic liquid-based dynamic microwave-assisted extraction, off-line ethanol-based dynamic microwave-assisted extraction, ionic liquid-based ultrasonic-assisted extraction, and ionic liquid-based maceration extraction. The results indicated that the proposed method is effective for the extraction of the active components in Chinese herbal medicine and has some advantages over the other methods. [ABSTRACT FROM AUTHOR]

Advancement of RNAi therapies is mainly hindered by the development of efficient delivery vehicles. The ability to create small size (<30 nm) oligonucleotide nanoparticles is essential for many aspects of the delivery process but is often overlooked. In this report, we describe diblock star polymers that can reproducibly complex double-stranded oligonucleotides into monodisperse nanoparticles with 15, 23, or 30 nm in diameter. The polymer-nucleic acid nanoparticles have a core-shell architecture with dense PEG brush coating. We characterized these nanoparticles using ITC, DLS, FRET, FCS, TIRF, and TEM. In addition to small size, these nanoparticles have neutral zeta-potentials, making the presented polymer architecture a very attractive platform for investigation of yet poorly studied polyplex size range for siRNA and antisense oligonucleotide delivery applications.

Here we show that the multifunctionality of Janus particles can be exploited for in vitro T cell activation. We engineer bifunctional Janus particles on which the spatial distribution of two ligands, anti-CD3 and fibronectin, mimics the "bull's eye" protein pattern formed in the membrane junction between a T cell and an antigen-presenting cell. Different levels of T cell activation can be achieved by simply switching the spatial distribution of the two ligands on the surfaces of the "bull's eye" particles. We find that the ligand pattern also affects clustering of intracellular proteins. This study demonstrates that anisotropic particles, such as Janus particles, can be developed as artificial antigen-presenting cells for modulating T cell activation.