Reduced-reference (RR) image quality assessment (IQA) method aims to accurately measure quality with part of the reference data. The challenge for RR IQA is how to effectively represent the visual content of an image with limited data for quality measurement. Inspired by the orientation selectivity (OS) mechanism in the primary visual cortex, we introduce an OS based visual pattern (OSVP) to extract visual content for RR IQA. The OS arises from the arrangement of the excitatory and inhibitory interactions among connected cortical neurons. Inspired by this, we investigate the correlation among neighbor pixels, and propose the OSVP to represent the visual content of an image. Then, the quality degradation is measured as the changes of OSVP, and a novel RR IQA model is proposed. Experimental results demonstrate that the OSVP based RR IQA model uses limited reference data (9 values) and performs highly consistent with the subjective perception.

Electron transfer and lithium ion diffusion rates are the key factors limiting the lithium ion storage in anisotropic LiFePO4 electrodes. In this work, we employed a facile solvothermal method to synthesize a "platelet-on-sheet" LiFePO4/graphene composite (LFP@GNs), which is LiFePO4 nanoplatelets in situ grown on graphene sheets with highly oriented (010) facets of LiFePO4 crystals. Such a two-phase contact mode with graphene sheets cross-linked to form a three-dimensional porous network is favourable for both fast lithium ion and electron transports. As a result, the designed LFP@GNs displayed a high rate capability (∼56 mA h g(-1) at 60 C) and long life cycling stability (∼87% capacity retention over 1000 cycles at 10 C). For comparison purposes, samples ex situ modified with graphene (LFP/GNs) as well as pure LiFePO4 platelets (LFP) were also prepared and investigated. More importantly, the obtained LFP@GNs can be used as a basic unit for constructing more complex structures to further improve electrochemical performance, such as coating the exposed LFP surface with a thin layer of carbon to build a C@LFP@GN composite to further enhance its cycling stability (∼98% capacity retention over 1000 cycles at 10 C).

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This review study indicates that JNK pathway plays an important role in development and progression of OA, and targeting the JNK pathway might be a potential approach for the treatment of OA in future.