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Abnormal activation of astrocytes in the amygdala contributes to anxiety after hemorrhagic shock and resuscitation (HSR). Nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB)-associated epigenetic reprogramming of astrocytic activation is crucial to anxiety. A bioactive monomer derived from Epimedium icariin (ICA) has been reported to modulate NF-κB signaling and astrocytic activation. The present study aimed to investigate the effects of ICA on post-HSR anxiety disorders and its potential mechanism of action. We first induced HSR in mice through a bleeding and re-transfusion model and selectively inhibited and activated astrocytes in the amygdala using chemogenetics. Then, ICA (40 mg/kg) was administered by oral gavage once daily for 21 days. Behavioral, electrophysiological, and pathological changes were assessed after HSR using the light-dark transition test, elevated plus maze, recording of local field potential (LFP), and immunofluorescence assays. Exposure to HSR reduced the duration of the light chamber and attenuated open-arm entries. Moreover, HSR exposure increased the theta oscillation power in the amygdala and upregulated NF-κB p65, H3K27ac, and H3K4me3 expression. Contrarily, chemogenetic inhibition of astrocytes significantly reversed these changes. Chemogenetic inhibition in astrocytes was simulated by ICA, but chemogenetic activation of astrocytes blocked the neuroprotective effects of ICA. ICA mitigated anxiety-like behaviors induced by HSR in mice via inhibiting astrocytic activation, which is possibly associated with NF-κB-induced epigenetic reprogramming. [ABSTRACT FROM AUTHOR]

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.ejor.2009.10.010 Byline: Jianyong Chen, Qiuzhen Lin, Zhen Ji Keywords: Multiple objective programming; Artificial immune systems; Clonal selection principle; Hybrid mutation; Artificial intelligence Abstract: In this paper, we develop a hybrid immune multiobjective optimization algorithm (HIMO) based on clonal selection principle. In HIMO, a hybrid mutation operator is proposed with the combination of Gaussian and polynomial mutations (GP-HM operator). The GP-HM operator adopts an adaptive switching parameter to control the mutation process, which uses relative large steps in high probability for boundary individuals and less-crowded individuals. With the generation running, the probability to perform relative large steps is reduced gradually. By this means, the exploratory capabilities are enhanced by keeping a desirable balance between global search and local search, so as to accelerate the convergence speed to the true Pareto-optimal front in the global space with many local Pareto-optimal fronts. When comparing HIMO with various state-of-the-art multiobjective optimization algorithms developed recently, simulation results show that HIMO performs better evidently. Author Affiliation: Department of Computer Science and Technology, Shenzhen University, Shenzhen 518060, PR China Article History: Received 8 September 2008; Accepted 14 October 2009

• A localized meshless method is proposed for the transient thermoelastic analysis. • A split-step method is proposed to improve the computational efficiency. • The proposed method can achieve more accurate results than the FEM in less time. • 3D thermoelastic problems are solved effectively using the proposed method. In this paper, a meshless collocation method, which combines the localized method of fundamental solutions (LMFS) with the Laplace transformation technique, is proposed for 3D uncoupled quasi-static thermoelasticity problems. The time domain thermoelasticity problem is transformed into Laplace domain first. Then, based on the Laplace domain fundamental solutions, the LMFS formulation is derived. Its sparse coefficient matrices make it available for large scale problems. To enhance the computational efficiency of the direct formulation of the LMFS, the LMFS is carried out by a split-step formulation. Based on the LMFS solutions in the Laplace space, the time domain results are finally obtained via numerical inversion of Laplace transforms. Three examples are presented to show the feasibility and accuracy of the proposed methods in which the superiority of the split-step formulation to the direct formulation is verified. Furthermore, the advantages of the LMFS are also discussed compared to the traditional method of fundamental solutions (MFS) and finite element method (FEM). [ABSTRACT FROM AUTHOR]

In this paper, an improved localized boundary knot method (LBKM) is proposed for 3D acoustic problems. The domain is divided into many small subdomains, and the solutions at the nodes of each subdomain are approximated by using the linear combination of the non-singular general solutions in the LBKM. However, the interpolant matrix generation for each subdomain in the original LBKM is associated with the variables at both domain and boundary nodes. In the present method, only the variables at domain nodes are considered for the matrix generation, and the boundary conditions are directly imposed during the matrix generation. As a consequence, the computational efficiency of the LBKM should be raised. Two examples are provided to illustrate the performance of the present method. [ABSTRACT FROM AUTHOR]