RESUMEN
Nitrogen fixation is a key process that sustains life on Earth. Nitrogenase is the sole enzyme capable of fixing nitrogen under ambient conditions. Extensive research efforts have been dedicated to elucidating the enzyme mechanism and its artificial activation through high applied voltage, photochemistry, or strong reducing agents. Harnessing light irradiation to minimize the required external bias can lower the process's high energy investment. Herein, we present the development of photo-bioelectrochemical cells (PBECs) utilizing BiVO4/CoP or CdS/NiO photoanodes for nitrogenase activation toward N2 fixation. The constructed PBEC based on BiVO4/CoP photoanode requires minimal external bias (200 mV) and suppresses O2 generation that allows efficient activation of the nitrogenase enzyme, using glucose as an electron donor. In a second developed PBEC configuration, CdS/NiO photoanode was used, enabling bias-free activation of the nitrogenase-based cathode to produce 100 µM of ammonia at a faradaic efficiency (FE) of 12%. The ammonia production was determined by a commonly used fluorescence probe and further validated using 1H-NMR spectroscopy. The presented PBECs lay the foundation for biotic-abiotic systems to directly activate enzymes toward value-added chemicals by light-driven reactions.
Asunto(s)
Técnicas Biosensibles , Nitrogenasa , Nitrogenasa/química , Nitrogenasa/metabolismo , Amoníaco/química , Fijación del Nitrógeno , Nitrógeno/químicaRESUMEN
BACKGROUND: Harmful preadolescent sexual behavior (HPSB) is an understudied phenomenon in the field of child sexual abuse (CSA). OBJECTIVE: The purpose of the present study was to analyze and describe the experiences and perceptions of adult survivors of HPSB. PARTICIPANTS AND SETTING: 16 survivors of HPSB were recruited as part of a purposeful sample. Their ages at the time of the study ranged from 21 to 50; they were Jewish-Israeli, secular, and Hebrew-speaking. METHODS: Semi-structured interviews and qualitative thematic analysis were conducted based on a descriptive phenomenological-psychological approach. RESULTS: Participants described elements of complexity in their perceptions of the "truthiness" of their memories and the mutuality of the HPSB experiences, as well as their primacy, seriousness, and life impact. They also described elements of support during disclosure, but mostly exposed the challenges and hardship involved, particularly the lack of legitimacy in exposing harmful sexual behavior perpetrated by other children. CONCLUSIONS: Both the HPSB experiences themselves and the subsequent disclosure contributed to the development of detached, mistrustful identities among the participants.