[ES] Una de las herramientas más utilizadas de la Biotecnología son las moléculas sonda fluorescentes que permitan extraer información analítica, no sólo cualitativa sino sobre todo cuantitativa, de diferentes procesos biológicos. Desde el punto de vista químico, todos estos compuestos presentan unas características fisicoquímicas especialmente apropiadas para cada aplicación concreta, pero todas ellas deben presentar una alta solubilidad en medios acuosos y fluidos biológicos. En este sentido, la búsqueda de nuevos quimiosensores debe enfocarse, por un lado, al diseño y síntesis de moléculas altamente fluorescentes capaces de modificar sus propiedades fotofísicas al interaccionar con analitos de importancia biológica y, por otro lado, aumentar su hidrosolubilidad y selectividad por los compuestos diana deseados. Por todo ello, la familia de derivados de perileno en general y las perilenodiimidas en particular presentan estos requisitos para poder ser aplicados en sistemas de detección biotecnológicos. Así, se pretende sintetizar una perilenodiimida bifuncionalizada mediante la condensación de dos unidades perilenomonoanhídridodiéster con cadenas pegiladas derivadas del etilenglicol que, por un lado, aumenten la solubilidad de la molécula en medios biológicos y, por otro lado, sirven para interaccionar con cationes fisiológicamente importantes debido a interacciones con dichas cadenas | [EN] One of the most used tools of biotechnology are fluorescent probe molecules which can extract, not only qualitative but mostly quantitative analytical information, about different biological processes. From the chemical point of view, all these compounds have the appropriate physicochemical features for each particular application, but all of them should have a high solubility in aqueous media and biological fluids. As a result, the search for new chemosensors should focus on the one hand, on the design and synthesis of highly fluorescent molecules capable to modify their photophysical properties at the time they interact with analytes of biological significance and, on the other hand, increase their water solubility and selectivity for desired target compounds. Therefore, the family of perylene derivatives in general and perylenediimides in particular present these requirements to be applied in biotechnological systems detection. Thus, it is intended to synthesize a bifunctionalized perylendiimide by condensing two units of perylenemonoanhidridediester with pegylated chains derived from ethylene glycol in order to, on the one hand, increase the solubility of the molecule in biological media and, on the other hand, serve to interact with physiologically important cations due to interactions with such chains. | Montes Navajas, PM. (2017). Síntesis de perilenodiimidas solubles en agua como sensores fluorescentes. http://hdl.handle.net/10251/89640

El objetivo de este trabajo fue comparar, con valores ya publicados y otros tomados para este fin, las características ecofisiológicas (potencial hídrico, ψ, fotosíntesis, A; conductancia estomática, gs; eficiencia instantánea de uso de agua, EUA; ganancia diaria de carbono integrada, AD; eficiencia cuántica relativa del PSII, ΦPSII ) en especies xerófitas de diferentes formas de vida y metabolismo fotosintético en cuatro localidades costeras del norte de Venezuela durante los períodos de lluvia y sequía. Los valores de ψ de todas las especies variaron en un intervalo de -0.3 a -4.8 MPa. Las mayores A (22 μmol m-2 s-1) y gs (0.4 mol m-2 s-1) fueron observadas en Calotropis procera en el período de lluvia y las menores (1 μmol m-2 s-1 de A y 0.03 mol m-2 s-1 de gs) en Cissus trifoliata en sequía. Todas las formas de vida estudiadas mostraron una alta correlación lineal entre A y gs. La fotosíntesis máxima diurna (Amax) permitió estimar la AD en muchas de las especies estudiadas. La EUA disminuyó con la sequía en las formas de vida caducifolias, mientras que permaneció constante en árboles y arbustos siempreverdes e incrementó en las hierbas. La sequía causó un descenso en ΦPSII acoplado a un incremento en el coeficiente de extinción no fotoquímico (NPQ), lo cual sugiere una regulación descendente del aparato fotoquímico. | This work compares, with values already published and others taken for this purpose, the ecophysiological characteristics (water potential, ψ, photosynthetic rate, A; stomatal conductance, gs; water use efficiency, WUE; integrated daily carbon gain, AD; and PSII relative quantum efficiency, ΦPSII) in xerophytes of different life forms and photosynthetic metabolisms in four northern coastal locations of Venezuela in the rainy and dry seasons. Water potential of all species varied between -0.3 and -4.8 MPa. The highest A (22 μmol m-2 s-1) and gs (0.4 mol m-2 s-1) were found during the rainy season in Calotropis procera while the lowest (1 μmol m-2 s-1, A and 0.03 mol m-2 s-1, gs) corresponded to Cissus trifoliata during the dry season. In all life forms A was highly correlated to gs. Daily carbon gain in most of the studied species may be estimated from maximum photosynthetic rate (Amax). In deciduous life forms, WUE was reduced with drought, whereas it did not change in evergreen trees and shrubs and decreased in herbs. Drought reduced ΦPSII while non-photochemical quenching (NPQ) increased, suggesting down-regulation of the photochemical system. | El Consejo de Desarrollo Científico de la Universidad Central de Venezuela financió esta investigación con las subvenciones CDCH PI 03-33-5383-2006 y CDCH PI 03.5733.2007/2.

18 pages, 15 figures, 3 tables | [EN] In a global context of climate change affecting the marine environment, it is important to consider the effect of extreme events in driving ecological change and to gain a better understanding of conditions to be expected under future scenarios. In this study we focus on monthly oceanographic data collected off Barcelona city during the period 2002-2012, in which extreme air temperatures and exceptional oceanographic events were reported in the western Mediterranean basin. These included two extreme heat waves and major episodes of dense water formation that produced unusually large deep-water contributions, induced oceanographic changes in the coastal zone and caused significant alterations to the marine ecosystem. To determine whether routine monitoring of oceanographic variables in a coastal zone can provide information for recognizing such large-scale events, temperature, salinity, turbidity and fluorescence were analysed to identify their signatures. The results provide an additional tool for monitoring oceanographic events and improving forecasts and future projections | [ES] En un contexto global de cambio climático es importante considerar los efectos que producen los eventos extremos de escala regional sobre la ecología de las zonas costeras, para conseguir una mejor comprensión de las condiciones esperables en futuros escenarios. En este trabajo se aborda el estudio de una serie temporal de parámetros oceanográficos obtenida frente a la ciudad de Barcelona durante el período 2002-2012, cuando en el Mediterráneo occidental se identificaron episodios de temperaturas extremas y eventos oceanográficos poco habituales. Estos episodios incluyen dos olas de calor severas y episodios de formación de agua densa de especial intensidad que alcanzaron profundidades inusuales, indujeron a cambios oceanográficos en la zona costera y causaron alteraciones significativas del ecosistema marino a escala regional. La monitorización rutinaria de parámetros oceanográficos en la zona costera ha demostrado ser una herramienta valiosa para identificar estos eventos de gran escala y caracterizar su huella a partir de las medidas de temperatura, salinidad, turbidez y fluorescencia en la columna de agua. Los resultados obtenidos proporcionan una herramienta adicional para la monitorización de eventos oceanográficos y para mejorar su predicción | The sampling also received funding from the HABES (Ref. EVK2-CT-2000-00092), PUDEM (Ref.REN2003-06637-C02) and SEDMET (Ref. CTM2006–06919) projects. JG, PP, GS and AP belong to the CRG on Littoral and Oceanic Processes, supported by Grant 2014 SGR 1642 of the Generalitat of Catalonia | Peer Reviewed

Variations in the sedimentary organic matter were documented throughout the Agua de la Mula Member (late Hauterivian) of the Agrio Formation, at a combined section in the type area of the Agrio Formation; the base at Agrio del Medio and the middle to top at Bajada del Agrio. A main organic-rich interval was identified in the basal Agua de la Mula Member, dominated by marine-derived Amorphous Organic Matter (AOM), coinciding with the highest Total Organic Carbon (TOC) content, between 1.4 and 3.8 wt.%, suggesting dysoxic conditions. The rest of the Member is predominantly characterized by terrestrially-derived organic matter, mainly phytoclasts, with low TOC values, around 1% or lower, indicating predominantly oxic depositional settings. By integrating stacking pattern and shell beds analysis, four depositional sequences SQ1–SQ4 were recognized. The organic-rich, finely laminated bituminous black shales of the Spitidiscus riccardii zone constitute a mayor and rapid inundation defining a Transgressive System tract (TST), related to a third order asymmetrical mesosequence dominated by a thick High System Tract (HST). It represents the most widespread and important flooding episode within the Neuquén Basin during the late Hauterivian. Inside sequences of higher frequency (SQ1, SQ2, SQ3, SQ4) of probably fourth order were recognized and analysed including several ammonids zones (Spitidiscus riccardii, Crioceratites schlagintweiti, C. diamantensis and Paraspiticeras groeberi). With the exception of the oxygen-controlled, basinal and outer ramp settings indicated for the TST1, which is equivalent to the TST of a lower order sequence, and the lower TST2, respectively, the prevalence of well oxygenated, inner to middle ramp depositional environments, is suggested for the rest of the sedimentary succession and emphasized in HST of SQ2, SQ3 and SQ4. Thus, a shallowing-upward trend with improved oxygenation is recorded through the Agua de la Mula Member, reflected by decreasing TOC, AOM content and preservation state of the organic matter. Based on the whole rock fluorescence analysis of the two selected organic-rich intervals from the Spitidiscus riccardii and the lowermost Crioceratites diamantensis zones, the presence of hydrocarbons suggests a very early in situ generation.