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Y chromosome abnormalities are frequently associated with male infertility. Men with ring Y chromosomes can present with sexual infantilism, ambiguous genitalia, hypospadias, or azoospermia. AZF microdeletions can result in spermatogenic defects in such patients. Here, we report an unusual karyotype of 45,X/46,X,r(Y)/46,X,dic r(Y) in an azoospermic man. However, the reason for this patient's azoospermia is not an AZF microdeletion but might be the abnormal structure of the r(Y) chromosome, the 45,X cell line, mosaicism of the 3 cell lines, or another unknown cause. In such cases, if the couple wishes to reproduce, cytogenetic, molecular and fluorescent in situ hybridization evaluations should be performed, and preimplantation genetic diagnosis should be used together with assisted reproductive technology. © 2013 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Abstract: Debris flows, landslides and rock falls are severe abrupt mass movement hazards, whose recorded occurrence in China has increased markedly in the past two decades. With the county- and city-based data, the debris flow hazard zonation for China was accomplished using the Rapid Zonation of Abrupt Mass-movement Hazard (RZAMH) approach, whose principles are described in the Part I companion paper. The entire area of China was classified into five regions with different degrees of hazard. Landslide and rock-fall hazard zonations for China were also presented. A sensitivity analysis demonstrated the robustness of the RZAMH approach. Direct validation was made with comparison of the zonation results and historical recordings on occurrence distribution of debris flows. The zonations produced by the RZAMH approach and other methods were compared by similarity analysis and paired-sample t-tests for the indirect validation of the accuracy of the RZAMH approach. [Copyright &y& Elsevier]

Abstract: The anode-supported solid state fuel cells were fabricated by tape-casting and co-sintering techniques. The effects of Ag-(La0.8Sr0.2)0.95MnO3 (LSM95) current-collecting layer at the cathode side on the electrochemical stability of anode-supported solid oxide fuel cells were investigated. The assembled cell was electrochemically characterized from 800 to 700°C with humidified H2 as fuel and O2 as oxidant. The open circuit voltages decreased with decreasing temperature which were opposite from the results calculated from the Nernst equation for each temperature, and the values were 1.14, 1.09 and 1.03V at 800, 750 and 700°C, respectively. EDX analysis revealed that Ag diffused from the cathode current-collecting layer to the surface of electrolyte which was caused by Ag electromigration under current. The phenomenon of Ag electromigration led to unstable cell performance during long-time operation. [Copyright &y& Elsevier]

Abstract: A Ni/scandia-stabilized zirconia (ScSZ) cermet anode was modified by coating with nano-sized gadolinium-doped ceria (GDC, Gd0.2Ce0.8O2) within the pores of the anode for a solid oxide fuel cell (SOFC). X-ray diffraction (XRD) and scanning electron microscopy (SEM) were employed in the anode characterizations. Open circuit voltages (OCVs) increased from 1.027 to 1.078V, and the maximum power densities increased from 238 to 825mW/cm2, as the operating temperature of a SOFC with 2.0wt.%GDC-coated Ni/ScSZ anode was increased from 700 to 850°C in humidified hydrogen. The coating of nano-sized Gd0.2Ce0.8O2 particle within the pores of the porous Ni/ScSZ anode significantly improved the performance of anode supported cell. Electrochemical impedance spectra (EIS) illustrated that the cell with Ni/ScSZ anode exhibited far greater impedances than the cell with 2.0wt.%GDC-coated Ni/ScSZ anode. Consequently, 2.0wt.%GDC-coated Ni/ScSZ anode could be used as a novel anode material for a SOFC due to better electrochemical performance. [Copyright &y& Elsevier]