The Fixed Points of Solutions of Some q

The purpose of this paper is to investigate the fixed points of solutions f(z) of some q-difference equations and obtain some results about the exponents of convergence of fixed points of f(z) and f(qjz)  (j∈N+), q-differences Δqf(z)=f(qz)-f(z), and q-divided differences Δqf(z)/f(z)

Multimodal estimation of distribution algorithms

Taking the advantage of estimation of distribution algorithms (EDAs) in preserving high diversity, this paper proposes a multimodal EDA. Integrated with clustering strategies for crowding and speciation, two versions of this algorithm are developed, which operate at the niche level. Then these two algorithms are equipped with three distinctive techniques: 1) a dynamic cluster sizing strategy; 2) an alternative utilization of Gaussian and Cauchy distributions to generate offspring; and 3) an adaptive local search. The dynamic cluster sizing affords a potential balance between exploration and exploitation and reduces the sensitivity to the cluster size in the niching methods. Taking advantages of Gaussian and Cauchy distributions, we generate the offspring at the niche level through alternatively using these two distributions. Such utilization can also potentially offer a balance between exploration and exploitation. Further, solution accuracy is enhanced through a new local search scheme probabilistically conducted around seeds of niches with probabilities determined self-adaptively according to fitness values of these seeds. Extensive experiments conducted on 20 benchmark multimodal problems confirm that both algorithms can achieve competitive performance compared with several state-of-the-art multimodal algorithms, which is supported by nonparametric tests. Especially, the proposed algorithms are very promising for complex problems with many local optima

Triangular bounded consistency of fuzzy preference relations

There are typically two types of consistency of fuzzy preference relations (FPR), namely additive and multiplicative consistency. They are defined based on the assumption that decision makers are rational and can provide strictly consistent FPRs. To take into consideration the bounded rationality of decision makers, the current study relaxes this assumption and proposes a new measure called triangular bounded consistency for judging the consistency of FPRs. To define triangular bounded consistency, a directed triangle is used to represent three FPRs among any three alternatives, with each directed edge representing an FPR. The condition of restricted max–max transitivity (RMMT) in the directed triangle is quantitatively examined. Under the assumption that the bounded rationality of a decision maker is characterized by their historical FPRs, which are represented by directed triangles that satisfy RMMT, triangular bounded consistency is determined using the historical FPRs. We then illustrate how triangular bounded consistency can be used to verify the consistency of FPRs that are newly provided by decision makers and how to estimate some missing FPRs that are not provided by decision makers. Finally, to demonstrate the application of triangular bounded consistency of FPRs in multi-attribute decision analysis, we investigate a problem that involves selecting areas to market products for a company

Styrene-assisted maleic anhydride grafted poly(lactic acid) as an effective compatibilizer for wood flour/poly(lactic acid) bio-composites

This study aimed to evaluate the effect of styrene-assisted maleic anhydride-grafted poly(lactic acid) (PLA-g-St/MAH) on the interfacial properties of wood flour/poly(lactic acid) (PLA) bio-composites. PLA-g-St/MAH was synthesized by free-radical melt grafting using styrene as a comonomer and dicumyl peroxide as an initiator. The structure of PLA-g-St/MAH was characterized by Fourier transform infrared spectroscopy. Wood flour/PLA composites were prepared by compression molding using PLA-g-St/MAH as a compatibilizer. The effects of PLA-g-St/MAH on the rheological and mechanical properties, as well as on the fractured surface morphology of the composites were investigated. Results indicated that storage modulus, complex viscosity, equilibrium torque, and shear heat were significantly increased. The mechanical properties of the wood flour/PLA composites were also significantly increased after the addition of PLA-g-St/MAH. The maximum values were achieved at the loading rate of 3 wt % because of the improved interfacial adhesion between the wood flour and the PLA matrix

Hexaaqua­nickel(II) bis­[4-(2-hydroxy­benzyl­ideneamino)benzene­sulfonate]

In the title compound, [Ni(H2O)6](C(C13H10NO4S)2, the nickel(II) atom, lying on a center of symmetry, is six-coordinated by six aqua O-atom donors. The dihedral angle between the two benzene rings is 33.1 (3)°. The crystal structure is stabilized by aqua–anion O—H⋯O hydrogen bonds. Intra­molecular O—H⋯N and C—H⋯O hydrogen-bonding inter­actions occur in the anion

Pharmacological isolation of postsynaptic currents mediated by NR2A- and NR2B-containing NMDA receptors in the anterior cingulate cortex

NMDA receptors (NMDARs) are involved in excitatory synaptic transmission and plasticity associated with a variety of brain functions, from memory formation to chronic pain. Subunit-selective antagonists for NMDARs provide powerful tools to dissect NMDAR functions in neuronal activities. Recently developed antagonist for NR2A-containing receptors, NVP-AAM007, triggered debates on its selectivity and involvement of the NMDAR subunits in bi-directional synaptic plasticity. Here, we re-examined the pharmacological properties of NMDARs in the anterior cingulate cortex (ACC) using NVP-AAM007 as well as ifenprodil, a selective antagonist for NR2B-containing NMDARs. By alternating sequence of drug application and examining different concentrations of NVP-AAM007, we found that the presence of NVP-AAM007 did not significantly affect the effect of ifenprodil on NMDAR-mediated EPSCs. These results suggest that NVP-AAM007 shows great preference for NR2A subunit and could be used as a selective antagonist for NR2A-containing NMDARs in the ACC

Licoflavanone exerts anticancer effects on human nasopharyngeal cancer cells via caspase activation, suppression of cell migration and invasion, and inhibition of m-TOR/PI3K/AKT pathway

Purpose: To study the anticancer effect of licoflavanone against human nasopharyngeal HKI carcinoma, and the mechanism involved. Methods: The 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay was used to determine the effect of licoflavanone on cell viability, while DAPI staining and western blotting were used to study its proapoptotic effect. Morphological examination was performed under phase contrast microscopy. Transwell chamber assays were used to study cell migration and invasion. The expression levels of mTOR/PI3K/AKT signal pathway-related proteins were assayed by Western blotting. Results: Licoflavanone markedly suppressed the proliferation of nasopharyngeal HK1 cancer cells in a concentration-reliant pattern (p < 0.01). The anticancer effects of licoflavanone were mediated via induction of pro-apoptotic effects and blocking of mTOR/PI3K/AKT signal pathway. Licoflavanone enhanced the activities of caspase-3, caspase-8, caspase-9 and cleaved caspase-3, as well as Bax and Bad. Moreover, licoflavanone blocked the migration and invasion of HK1 nasopharyngeal cancer cells. Conclusion: Licoflavanone exerts potent anticancer effects on human nasopharyngeal cancer cells via caspase activation, inhibition of cell migration and cell invasion, and down-regulation of m-TOR/PI3K/AKT signal pathway. Therefore, licoflavanone may be a useful lead drug for the development of a treatment strategy for nasopharyngeal cancer