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In this experimental study, electrolyte-supported solid oxide fuel cells (SOFCs) with two different anodes were investigated. Specifically, the stability of cells with a nickel/8 mol % yttria-stabilized zirconia (Ni/8YSZ) cermet anodes was compared to those based on nickel/40 mol % gadolinia-doped ceria (Ni/CG40). For this, the cells were characterized by impedance spectroscopy as well as by four-point electrical conductivity measurements. A high frequency process was observed in the Ni/8YSZ anode, which was not detected in the Ni/CG40 anode. After eight redox cycles at 950°C , the cell with the Ni/8YSZ anode showed an increase in the polarization resistance mainly in the high frequency domain. However, the cell with the Ni/CG40 anode showed an increase in both ohmic and polarization resistances, the latter mainly in the low frequency domain. Compared with Ni/CG40, the degradation in Ni/8YSZ upon redox cycling was higher at 850°C but lower at 950°C . For the Ni/8YSZ anode, a significant degradation was seen in the first 3 h after a redox cycle. The increase in the ohmic resistance of the Ni/CG40-based cell is believed to correlate with a decrease in the electrical conductivity of the anode. The latter showed a strong decrease upon a subsequent redox cycling at 950°C . For the Ni/CG40 anode, the degradation in both the conductivity and electrochemical performance significantly improved by decreasing the operation temperature from 950 to 850°C .

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Prostatic diseases are a common health problem among males in Western countries, and include chronic prostatic diseases, which have an unclear pathogenesis and few treatment options. In vitro and in vivo studies describe oxidative stress as a major pathway involved in the occurrence of benign prostatic hyperplasia, prostatic cancer and chronic prostatitis. Thus, the oxidative stress cascade is a potential target for the treatment of prostatic diseases. This paper presents a systematic review of the available data concerning the association between oxidative stress and the most common chronic prostatic diseases, and describes the available treatment options that act upon this pathway.

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