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The development of efficient and compact photonic systems in support of mid-infrared integrated optics is currently facing several challenges. To date, most mid-infrared glass-based devices are employing fluoride or chalcogenide glasses (FCGs). Although the commercialization of FCGs-based optical devices has rapidly grown during the last decade, their development is rather cumbersome due to either poor crystallization and hygroscopicity resilience or poor mechanical-thermal properties of the FCGs. To overcome these issues, the parallel development of heavy-metal oxide optical fiber from the barium-germanium-gallium oxide vitreous system (BGG) has revealed a promising alternative. However, over 30 years of fiber fabrication optimization, the final missing step of drawing BGG fibers with acceptable losses for meters-long active and passive optical devices had not yet been reached. In this article, we first identify the three most important factors that prevent the fabrication of low-loss BGG fibers i.e., surface quality, volumic striae and glass thermal-darkening. Each of the three factors is then addressed in setting up a protocol enabling the fabrication of low-loss optical fibers from gallium-rich BGG glass compositions. Accordingly, to the best of our knowledge, we report the lowest losses ever measured in a BGG glass fiber i.e., down to 200 dB km−1 at 1350 nm. [ABSTRACT FROM AUTHOR]

Leptospirosis is a disease widely prevalent in tropical areas, but may also be present in urban areas. The present study aims to determine the seroprevalence of Leptospira in the district of Puente Piedra, where there have been cases of severe leptospirosis in recent years. We collected data related to risk factors associated with leptospirosis and blood samples from 250 participants, selected by random sampling. We found a high prevalence of risk factors in the population and using the microscopic agglutination test, antibodies were found in only 3 participants (1.2%).