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The results of a study of electroluminescence of silicon vacancy color centers (SiV centers) in a diamond merged diode with a structure involving parallel connection of a p–i–n diode and a Schottky diode are presented. To create color centers, the inner region of the diode is doped with silicon. In the luminescence spectrum, only a line at a wavelength of 738 nm is detected, corresponding to the emission of a SiV color center in a negative charge state. Emission at a wavelength of 946 nm, corresponding to the SiV color center in the neutral charge state, is not detected. The electroluminescence of color centers is observed only in the p–i–n region of the diode, that is, it is experimentally demonstrated that both types of charge carriers are necessary to excite electroluminescence. A pronounced dependence of the photoluminescence intensity of SiV centers on the applied voltage is found. [ABSTRACT FROM AUTHOR]

Development of effective vaccine candidates against tuberculosis (TB) is currently the most important challenge in the prevention of this disease since the BCG vaccine fails to guarantee a lifelong protection, while any other approved vaccine with better efficiency is still absent. The protective effect of the recombinant fusion protein CFP10–ESAT6–dIFN produced in a prokaryotic expression system (Escherichia coli) has been assessed in a guinea pig model of acute TB. The tested antigen comprises the Mycobacterium tuberculosis (Mtb) proteins ESAT6 and CFP10 as well as modified human γ-interferon (dIFN) for boosting the immune response. Double intradermal immunization of guinea pigs with the tested fusion protein (2 × 0.5 µg) induces a protective effect against subsequent Mtb infection. The immunized guinea pigs do not develop the symptoms of acute TB and their body weight gain was five times more as compared with the non-immunized infected guinea pigs. The animal group immunized with this dose of antigen displays the minimum morphological changes in the internal organs and insignificant inflammatory lesions in the liver tissue, which complies with a decrease in the bacterial load in the spleen and average Mtb counts in macrophages. [ABSTRACT FROM AUTHOR]

Diamond is desired for active semiconducting device because of it high carrier mobility, high voltage breakdown resistance, and high thermal diffusivity. Exploiting diamond as a semiconductor is hampered by the lack of shallow dopants to create sufficient electronic carriers at room temperature. In this work, nanometer thick, heavily boron doped epitaxial diamond 'delta doped' layers have been grown on ultra smooth diamond surfaces which demonstrate p type conduction with enhanced Hall mobilities of up to 120 cm2/Vs and sheet carrier concentrations to 6 × 1013 cm-2, thus enabling a new class of active diamond electronic devices. (© 2016 WILEY-VCH Verlag GmbH &Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]