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Conductive polymer composites require high conductive filler loadings to achieve relatively ideal electromagnetic interference (EMI) shielding performance, which brings problems such as heavy weight and poor processability and ultimately limits their application in the aerospace field. To solve the above problems and realize the preparation of excellent EMI shielding composites with low filler loadings, a bipolar pulsed electric field-induced graphene nanoplatelets (GNPs) alignment method is proposed in this paper to improve the electrical conductivity and EMI shielding performance. The orientation and alignment of GNPs in the matrix were characterized by x-ray diffraction and scanning electron microscopy, and the results showed that GNPs formed a conductive network. The electrical conductivity of the composite material in the X-band was measured, and the results showed that the bipolar pulsed electric field could significantly improve the electrical conductivity of the composite material; the improvement percentage reached 100%–300% under the five filler loadings. In addition, the EMI shielding effectiveness of the composite material in the X-band was tested. The results showed that the EMI shielding effectiveness of the composite material with a mass fraction of 14% increased from 16.48–15.86 dB to 21.37–20.99 dB with the action of the bipolar pulsed electric field, and the improvement percentage was 32%. This is the first study on improving the EMI shielding performance of composite materials by applying a bipolar pulsed electric field, and it provides an effective method to prepare EMI shielding composites with low filler loadings. [ABSTRACT FROM AUTHOR]

Objective To identify differentially expressed genes (DEGs) and further analyze potential biological processes and pathways involved in isoflurane-induced anesthesia. Methods Microarray data (ID: GSE64617) from rat brains treated with exposure to either isoflurane in oxygen (2 %) (test group) or oxygen alone (control group) for 15 min were downloaded from Gene Expression Omnibus. Data pre-processing was performed using the Affy package, followed by DEG screening using the limma package. Protein-protein interactions (PPIs) among DEGs were obtained from STRING (Search Tool for the Retrieval of Interacting Genes/Proteins), and then visualized by constructing a network using Cytoscape. Functional and pathway enrichment analyses were further implemented to identify the biological processes and KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways enriched by DEGs. Results A total of 240 DEGs were identified between the test and control groups, including 128 up-regulated DEGs and 112 down-regulated DEGs in the test group, of which 17 DEGs with a connectivity degree >4 were identified as hub genes (e.g., Pik3r1 and Pik3r2) in the constructed PPI network. Additionally, Slc17a7 and Camk4 interacted with Syn1, and Pik3r1 interacted with Pik3r2. Enrichment analysis further revealed the significantly enriched biological processes of 'synaptic transmission', 'cell-cell signaling' and 'transmission of nerve impulse' (e.g., Slc17a7, Camk4, Syn1, Gria1, Prkcg and Lphn1), as well as KEGG pathways including 'focal adhesion', 'Fc [gamma] R-mediated phagocytosis' (e.g., Prkcg, Pik3r1 and Pik3r2), and 'regulation of actin cytoskeleton' (e.g., Pik3r1 and Pik3r2). Conclusions The identified DEGs significantly enriched in biological processes and KEGG pathways might be implicated in isoflurane-induced anesthesia., Author(s): Hai Wang[sup.1] , Yi Jin[sup.2] , Jinyan Dai[sup.1] Author Affiliations: (1) Department of Anesthesiology and Pain Medicine, Institute of Dermatology, Chinese Academy of Medical Sciences and Peking Union Medical [...]

One of the key challenges for the development of lithium‐ion batteries is the preparation of high‐performance anode materials. In this paper, a micro/nanostructured Si@SnS2‐rGO composite is reported in which Si nanoparticles with a particle size of 30 nm are electrostatically anchored on a 3D reduced graphene oxide (rGO) network and mixed with SnS2. The step‐wise lithiation/delithiation of SnS2 provided space‐constraining effects to accommodate volume expansion and particle aggregation, thereby alleviating the volume expansion of Si during cycling as well as enhancing the structural stability, whereas the rGO in the 3D network stabilized the composite. The composite had a high specific capacity of 1480.1 mAh g−1 after 200 cycles at a current density of 200 mA g−1 and a high stability at rates of 200–3000 mA g−1. The capacity attenuation after cycling was only 89.18 %. A stable specific capacity (425.5 mAh g−1) was achieved after 600 cycles at a current density of 3000 mA g−1. Therefore, the micro/nanostructured Si@SnS2‐rGO composite is a promising anode material for use in lithium‐ion batteries. [ABSTRACT FROM AUTHOR]