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Tantalum (Ta) oxides and their coatings have been proved to increase their applications in the biomedical fields by improving osseointegration and wear resistance. In this study, Ta oxide coatings containing different proportions of Ag are deposited on SS304 materials. A twin-gun magnetron sputtering system is used to deposit the tantalum oxide-Ag coating. In this study, Staphylococcus aureus, which exhibits physiological commensalism on the human skin, nares, and mucosal and oral areas, is chosen as the model for in vitro antibacterial analyses via a fluorescence staining method using Syto9. The cytocompatibility and adhesive morphology of human skin fibroblast cells (CCD-966SK) on the coatings are also determined by using the microculture tetrazolium assay. This study shows that Ta2O5 and Ta2O5-Ag coatings with 12.5 at. % of Ag exhibit improved antibacterial effects against S. aureus and have good skin fibroblast cell cellular biocompatibility.

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This paper presents an inverse scattering problem for through-wall imaging. Two separate perfect-conducting cylinders of unknown shapes are behind a homogeneous building wall and illuminated by the transverse magnetic (TM) plane wave. After an integral formulation, a discretization using the method of moment (MoM) is applied. The through-wall imaging (TWI) problem is recast as a nonlinear optimization problem with an objective function defined by the norm of a difference between the measured and calculated scattered electric field. Thus, the shape of the metallic cylinder can be obtained by minimizing the objective function. The asynchronous particle swarm optimization (APSO) is employed to find out the global extreme solution of the object function. Numerical results demonstrate that even when the initial guesses are far away from the exact shapes, and the multiple scattered fields between two conductors are serious, good reconstruction still can be obtained. In addition, the effect of Gaussian noise on the reconstruction result is investigated and the numerical simulation shows that even though the signal-noise ratio (SNR) is 20 dB, we can still get good results of reconstructions.

This paper presents a statistically-driven two-step flash sub-analog-to-digital converter (ADC) to construct the high-speed time-interleaved ADC in wireline communication applications. The comparators in the flash sub-ADC are divided into the large probability first stage and the small probability second stage to take advantage of the nonuniform probability distribution of the input signal. At the first step of operation, the large probability first stage is activated while the small probability second stage is suspended. If the input signal is beyond the input range of the first stage, the segment selection signal will trigger proper segment in the second stage. Feed-forward equalization is proposed to manipulate the probability distribution of the ADC input signal. A possible implementation of the proposed ADC as well as the modulation and equalization scheme is presented to comply with the IEEE 802.3ap 10[Formula: see text]G Ethernet standard. In the case of a PAM-4 pseudorandom signal, the proposed solution achieves [Formula: see text] reduction on the average number of activated comparators compared to a conventional flash ADC.