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Exponentiation in finite fields is an essential operation used in many applications ranging from error control coding to cryptographic computations, while representation in Gaussian normal basis (GNB) offers low complexity arithmetic, especially in hardware architectures. In this article, we propose several new hardware architectures for binary exponentiation in GNB. The proposed architectures make use of different levels of precomputation and the efficient digit-level parallel-in parallel-out, and hybrid-double multipliers. We support our new designs with novel countermeasures against side-channel analysis that require minimal implementation overhead. Moreover, we obtain implementation results for all architectures and provide realistic and fair comparisons with the previously known works available in the literature. It is shown that our newly proposed architectures outperform the existing hardware architectures in terms of area and time complexities and security. [ABSTRACT FROM AUTHOR]

Bridging strategies are required to repair peripheral nerve injuries that result in gaps >5–8 mm. Limitations such as donor‐site morbidity and size mismatches with receptor sites for autografts, together with immunological problems associated with allografts and xenografts, have created an increased interest in the field of manufactured nerve guide conduits. In this study, zein, a plant protein‐based polymer, was electrospun to prepare nanofibrous mats. An important challenge with zein mats is the rapid change from fibre to film under aqueous conditions. Tannic acid (TA), which is a polyphenol, was selected to prepare a blend of zein/TA with different weight ratios to investigate its effect on the wetting resistance of nanofibres. The electrospun mats were characterised and evaluated by Fourier transform infrared spectroscopy and scanning electron microscopy (SEM). Also, degradation and mechanical properties of the mats were studied. Results showed that TA had a significant effect on the resistance to film formation in nanofibres. Moreover, the degradation and elongation at break of mats were increased with increase in TA concentration. For the investigation of the peripheral nerve regeneration potential, Schwann cells were selected for cytotoxicity evaluation by the 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5 diphenyltetrazolium bromide assay and cell morphology by SEM. Schwann cells had good biocompatibility with zein/TA blends (%) of 90/10 and 80/20. [ABSTRACT FROM AUTHOR]

The multiplicative inverse over binary fields is one of main arithmetic operations used in cryptography. This paper presents two new inversion architectures. First, an improved architecture for classic inversion scheme using single multiplier is presented. The new improved inverter achieves lower latency through loading input registers during last multiplication cycle, at the expense of higher propagation delay. After this, a novel inversion architecture which uses half the latency to process the classic-based addition chains (or improved ones) is presented. The latter architecture, named Classical-Interleaved, is constructed based on a novel fully-serial-in square-multiply processor (FSISM). The FSISM, squares one operand, and multiply it to the second one, concurrently while the two inputs are absorbed serially digit-by-digit. The new classical inverter and the new classical-interleaved inverter reduce the latency compared to other schemes. In addition, the proposed classical and interleaved inverters outperform the original Itoh-Tsujii algorithm (ITA) and Ternary Itoh-Tsujii / optimal 3-chain algorithms in terms of its higher throughput and improved hardware efficiency for a number of digit sizes. The efficiency of the proposed field inverters are demonstrated by comparisons based on application specific integrated circuits (ASIC) implementations results using the standard 65 nm CMOS technology libraries. [ABSTRACT FROM AUTHOR]

Owing to their unique chemo-physical and structural characteristics, amorphous bulk metallic glasses (BMGs) are of great demand for fabrication of variety of advanced and innovative products including surgical and biomedical tools and devices. In this study, a series of Ni-free Zr-based BMGs in Zr-Cu-Fe-Al system are fabricated using copper-mold casting technique, and their biocorrosion and biocompatibility are evaluated with respect to their corrosion behavior in the phosphate buffered saline (pH = 7.4) solution. Anodic polarization curves, scanning electron microscopy combined with energy-dispersive X-ray, and wettability analyses are conducted to characterize the surfaces of BMG samples. The biocompatibility of the BMG and control samples is studied by comparing cell-substrate interactions among different samples. It is found that Zr60Cu20Fe10Al10 displays a higher passive region compared with that of Zr60Cu22.5Fe7.5Al10, but both BMGs exhibit lower corrosion resistance compared with Ti-6Al-4V alloy. By addition of titanium to Zr-Cu-Fe-Al system (Zr60Ti6Cu19Fe5Al10), a significant increase in the passive region of the polarization curve is detected. The cell culture experiments reveal that the number of attached and grown cells is significantly higher on the surface of the treated BMGs as compared with Ti-6Al-4V substrates and the culture plate as controls. There is no noticeable difference in cellular morphology among the BMG samples, and no cytotoxicity is detected. We speculate that the interaction of water molecules and matrix proteins with the surfaces of BMGs plays an important role in cell-substrate interactions and improved cell response. Copyright © 2013 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]