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Flexible pressure sensors present great potential in the application of human health monitoring, tactile function of prosthesis, and electronic skin for robotics. These applications require different trade-off between the sensitivity and sensing range, therefore, it is imperative to develop range-specific sensitivities in a single sensor. In this paper, a bioinspired strategy for a resistive pressure sensor using a graded porous material is proposed to measure pressures from several pascals to megapascals. Its fabrication is based on an easily accessible template method. The nest-architecture-based wide-range pressure sensor exhibits adequate sensitivity under an extensive pressure regime (20 Pa to 1.2 MPa). In addition, with rational structural design and subtle engineering of the material properties, the sensor achieves remarkable mechanical stability. To prove the concept, sensors were attached on a bicycle wheel to monitor the tire-pavement pressure and on human skin to detect biosignals such as venous and arterial blood pressure pulses.

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Synchrotron white-beam X-ray topography studies, in conjunction with Nomarski optical microscopy, have been carried out on 6H-SiC single crystals grown by the sublimation physical vapour transport technique. Two kinds of dislocations were observed using topography: dislocations exhibiting bimodal images of various widths and with line directions approximately parallel to the (0001) axis and dislocations confined to the basal plane, which appear to have emanated from the former dislocations. The larger bimodal image width dislocations were found to have hollow cores, known as 'micropipes'. Detailed contrast analysis of topographic images obtained in transmission and back-reflection geometries establishes that 'micropipes' are Frank-type hollow-core screw dislocations with Burgers vectors typically equal to 3-7 times the c lattice parameter. X-ray topography also revealed many line defects approximately parallel to the (0001) axis that were determined to be screw dislocations with Burgers vectors equal to the c lattice parameter and there were no discernible 'micropipes' associated with these latter screw dislocations.

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Fibroblast growth factor 21 (FGF-21) is an endocrine factor that can be secreted into circulation by the liver. FGF-21 takes part in metabolic actions and is thought to be a promising candidate for the treatment of diabetes. However, the role of FGF-21 in atherosclerosis is unknown. In this study, apoE(-/-) mice were fed an atherogenic diet for 4 weeks with and without subcutaneous injections of FGF-21. ApoE(-/-) mice fed an atherogenic diet showed hyperlipidemia, a large plaque area in aortas and increased vessel wall thickness. Plasma FGF-21 content and protein level of FGF receptor 1 (FGFR1) in aortas was greater in apoE(-/-) than C57BL/6J mice. Exogenous FGF-21 treatment significantly ameliorated dyslipidemia in apoE(-/-) mice. FGF-21-treated apoE(-/-) mice showed reduced number of aortic plaques and plaque area as well as reduced number of TUNEL-positive cells. Protein levels of the endoplasmic reticulum stress markers glucose-regulated protein 94, caspase-12 and C/EBP homologous protein were reduced by 34.5, 31.4 and 26.5 %, respectively, in apoE(-/-) mice. Endogenous expression of FGF-21 and its receptor FGFR1 were upregulated in apoE(-/-) mice, and exogenous administration of FGF-21 ameliorated the atherogenic-induced dyslipidemia and vascular atherosclerotic lesions. FGF-21 protecting against atherosclerosis might be in part by its inhibitory effects on endoplasmic reticulum stress-mediated apoptosis.