70 research outputs found

    Oxidation mechanism of formic acid on the bismuth adatom-modified Pt(111) surface

    Full text link
    In order to improve catalytic processes, elucidation of reaction mechanisms is essential. Here, supported by a combination of experimental and computational results, the oxidation mechanism of formic acid on Pt(111) electrodes modified by the incorporation of bismuth adatoms is revealed. In the proposed model, formic acid is first physisorbed on bismuth and then deprotonated and chemisorbed in formate form, also on bismuth, from which configuration the C-H bond is cleaved, on a neighbor Pt site, yielding CO2. It was found computationally that the activation energy for the C-H bond cleavage step is negligible, which was also verified experimentally.This work has been financially supported by the MINECO (Spain) (project CTQ2013-44083-P) and Generalitat Valenciana (project PROMETEOII/2014/013).Perales Rondón, JV.; Ferre Vilaplana, A.; Feliu, J.; Herrero, E. (2014). Oxidation mechanism of formic acid on the bismuth adatom-modified Pt(111) surface. Journal of the American Chemical Society. 136(38):13110-13113. https://doi.org/10.1021/ja505943hS13110131131363

    Ocean Circulation over North Atlantic underwater features in the path of the Mediterranean Outflow Water: Ormonde and Formigas seamounts, and the Gazul mud volcano

    Get PDF
    Seamounts constitute an obstacle to the ocean circulation, modifying it. As a result, a variety of hydrodynamical processes and phenomena may take place over seamounts, among others, flow intensification, current deflection, upwelling, Taylor caps, and internal waves. These oceanographic effects may turn seamounts into very productive ecosystems with high species diversity, and in some cases, are densely populated by benthic organisms, such corals, gorgonians, and sponges. In this study, we describe the oceanographic conditions over seamounts and other underwater features in the path of the Mediterranean Outflow Water (MOW), where populations of benthic suspensions feeders have been observed. Using CTD, LADPC and biochemical measurements carried out in the Ormonde and Formigas seamounts and the Gazul mud volcano (Northeast Atlantic), we show that Taylor caps were not observed in any of the sampled features. However, we point out that the relatively high values of the Brunt–Väisälä frequency in the MOW halocline, in conjunction with the slope of the seamount flanks, set up conditions for the breakout of internal waves and amplification of the currents. This may enhance the vertical mixing, resuspending the organic material deposited on the seafloor and, therefore, increasing the food availability for the communities dominated by benthic suspension feeders. Thus, we hypothesize that internal waves could be improving the conditions for benthic suspension feeders to grow on the slope of seamounts.En prens

    Cognitive impairment induced by delta9-tetrahydrocannabinol occurs through heteromers between cannabinoid CB1 and serotonin 5-HT2A receptors

    Get PDF
    Delta-9-tetrahydrocannabinol (THC), the main psychoactive compound of marijuana, induces numerous undesirable effects, including memory impairments, anxiety, and dependence. Conversely, THC also has potentially therapeutic effects, including analgesia, muscle relaxation, and neuroprotection. However, the mechanisms that dissociate these responses are still not known. Using mice lacking the serotonin receptor 5-HT2A, we revealed that the analgesic and amnesic effects of THC are independent of each other: while amnesia induced by THC disappears in the mutant mice, THC can still promote analgesia in these animals. In subsequent molecular studies, we showed that in specific brain regions involved in memory formation, the receptors for THC and the 5-HT2A receptors work together by physically interacting with each other. Experimentally interfering with this interaction prevented the memory deficits induced by THC, but not its analgesic properties. Our results highlight a novel mechanism by which the beneficial analgesic properties of THC can be dissociated from its cognitive side effects

    Agrocombustibles: ¿Otro negocio es posible?

    Get PDF
    Hoy en día, los agrocombustibles (principalmente biodiesel y bioetanol) son objeto de políticas públicas e incentivos, y se ha acelerado su producción a gran escala, con la intención de reducir las emisiones de gases de efecto invernadero, y por tanto contribuir a la mitigación del cambio climático. Las y los autores de este libro integran el Grup de Bionegocis, un espacio multidisciplinario impulsado desde la Campaña “No te Comas el Mundo”, que investiga en Cataluña desde el año 2007 sobre la temática de los agrocombustibles. El principal objetivo de esta publicación se ubica en profundizar algunos aspectos con el objetivo de brindar herramientas de reflexión y de acción. Pretende responder a preguntas tales como: ¿Qué son los agrocombustibles? ¿Es positivo su rendimiento energético? ¿Cuál es la huella hídrica de estos carburantes? ¿Son realmente una respuesta ante el calentamiento global? ¿De dónde proviene la materia prima? ¿Mejoran las condiciones de vida en los países del Sur? ¿Cuáles son los intereses corporativos en este rubro? ¿Generarán los agrocombustibles una mayor Deuda ecológica? ¿Es la segunda generación una respuesta adecuada? ¿Qué perspectivas tenemos ante la Soberanía alimentaria y la Soberanía energética?Peer reviewe

    Power, Food and Agriculture: Implications for Farmers, Consumers and Communities

    Full text link

    Building on Local Traditional Knowledge in South Asia

    No full text
    Local traditional knowledge (LTK) is advocated by many international development and research institutes, as well as by local NGOs and grassroots civil society. When discussed within the climate change adaptation community, it is heralded as a crucial untapped knowledge source that may hold the key to sustainable adaptation to climate change. Yet organizations and scientific literature have been much vaguer as to how to tap into these resources; whether they will remain relevant in the context of accelerating, unprecedented changes (in climate, economic structures, and demographics); and to what extent locally-produced and -tailored practices might be transferable/scalable to other areas.Peer reviewe
    corecore