The water footprint of olives and olive oil in Spain

This paper evaluates the water footprint of Spanish olives and olive oil over the period 1997-2008. In particular, it analyses the three colour components of the water footprint: green (rainwater stored in the soil), blue (surface and groundwater) and grey (freshwater required to assimilate load of pollutants). Apparent water productivity and virtual water embedded in olive oil exports have also been studied. Results show more than 99.5% of the water footprint of one liter of bottled olive oil is related to the olive production, whereas less than 0.5% is due to the other components such as bottle, cap and label. Over the studied period, the green water footprint in absolute terms of Spanish olive oil production represents about 72% in rainfed systems and just 12% in irrigated olive orchards. Blue and grey water footprints represent 6% and 10% of the national water footprint, respectively. It is shown that olive production is concentrated in regions with the smallest water footprint per unit of product. However, the increase of groundwater consumption in the main olive producing region (Andalusia), from 98 to 378 Mm3 between 1997 and 2008, has added significant pressure in the upstream Guadalquivir basin. This raises questions about the sustainability of irrigated olive orchards for export from the region. Finally, the virtual water related to olive oil exports illustrate the importance of green water footprint of rainfed olives amounting to about 77% of the total virtual water exports

Evidence of a new state in 11^{11}Be observed in the 11^{11}Li β\beta-decay

Coincidences between charged particles emitted in the $\beta$-decay of $^{11}$Li were observed using highly segmented detectors. The breakup channels involving three particles were studied in full kinematics allowing for the reconstruction of the excitation energy of the $^{11}$Be states participating in the decay. In particular, the contribution of a previously unobserved state at 16.3 MeV in $^{11}$Be has been identified selecting the $\alpha$ + $^7$He$\to\alpha$ + $^6$He+n channel. The angular correlations between the $\alpha$ particle and the center of mass of the $^6$He+n system favors spin and parity assignment of 3/2$^-$ for this state as well as for the previously known state at 18 MeV.Comment: 13 pages, 6 figure

Effect of charge regulation and conformational equilibria in the 2 stretching properties of weak polyelectrolytes

Weak polyelectrolytes can modulate their charge in response to external perturbations, such as changes in the pH, ionic strength (I), or electrostatic interactions with other charged species, a phenomenon known as charge regulation (CR). On the other hand, it is well established that CR is highly coupled with the conformational degrees of freedom. In this paper, the influence of CR in the stretching properties of weak polyelectrolytes is analyzed, and the possibility of CR induced by mechanical stretching is explored. With this aim, we make use of a minimal model, which captures the fundamental aspects present in the stretching of a flexible weak linear polyelectrolyte: internal angle rotation, bond stretching, bond bending, and proton binding, which is the paradigmatic mechanism of CR. The angle rotation is described by using the rotational isomeric state approximation, while for protonation, the site binding model is assumed. Mechanical stretching is studied by performing semi-grand canonical Monte Carlo simulations at different pH and ionic strength conditions. The simulations simultaneously provide both conformational (bond state probabilities, persistence length lP, and chain elongation) and protonation properties (degree of protonation θ and the effective protonation constant Kc). The obtained force−extension curves suggest that the pH value and the ionic strength I have a significant effect on polyelectrolyte stretching. Three different force regimes can be observed. For large forces (F > 100 pN for typical force constants), the force−extension curve is almost independent of the pH and I. For low forces, the persistence length lP is force-independent, although it strongly increases with the pH value. Under this regime, linear and Pincus scaling behaviors are observed. Finally, in the intermediate-force regime, both rotational and protonation degrees of freedom are mechanically activated, and the picture becomes more complicated. It is found that lP increases with F and, under certain conditions, a significant increase of θ with F is observed, indicating that CR could in principle be induced by means of mechanical stretching. This fact can be explained by analyzing the coupling between θ and the probability of a bond to be in the gauche state P(g). P(g) decreases with F as the bonds adopt the trans conformation so that the electrostatic repulsion is reduced and θ increases. Finally, the intricate interplay between short-range and long-range interactions is analyzed, leading to apparently contradictory behaviors (P(g) and lp simultaneously decrease with I), which can only be explained by CR and the presence of complex spatial correlations

Importancia del conocimiento de la huella hidrológica para la política española del agua

En casi todos los países áridos o semiáridos la adecuada gestión de los recursos hídricos es un tema tan importante como conflictivo. La mayor parte de los expertos en gestión de recursos hídricos suele admitir hoy que los conflictos hídricos no se deben normalmente a la escasez física de agua sino a su inadecuada gestión. Los avances en la Ciencia y en la Tecnología que se han producido en el último medio siglo permiten resolver muchos de los problemas relacionados con conflictos hídricos con medios que hace pocas décadas nadie podía imaginar. El presente documento se centra en el estudio de la HUELLA HIDROLÓGICA y sus relacionados conceptos de agua virtual y sus componentes verde y azul. Este trabajo se enfoca no sólo desde la clásica perspectiva hidrológica sino también enfatizando los datos económicos. El estudio de la huella hidrológica está haciendo cambiar los conceptos de seguridad alimentaria e hidrológica que han estado vigentes durante siglos en la mente de la mayor parte de los políticos de todo el mundo. Los datos disponibles ponen claramente de manifiesto que la producción de alimentos es, a escala mundial, el principal usuario de agua verde y azul a gran diferencia de los otros usos. Por ello, este trabajo preliminar de otros estudios en marcha, se dedica principalmente al estudio del agua en la agricultura. La política del agua de un país va a estar cada día más íntimamente relacionada con su política agrícola, tanto de producción de alimentos como de su importación y/o exportación. Al mismo tiempo hay que tener en cuenta que en los países industrializados, como es España, los condicionantes ambientales van adquiriendo más peso y que consciente o inconscientemente el viejo lema “more crops and jobs per drop” está cambiando al lema “more cash and nature per drop”

Production of PHB from Chicory Roots - Comparison of Three Cupriavidus necator Strains

Chicory roots from hydroponic salad cultivation are an abundant food residue in Navarra (Spain) that are underutilized to date. Aiming at a holistic utilization of resources, we report here the first process using chicory root hydrolysate for the production of poly([R]-3-hydroxybutyrate) (PHB). The polymer can be used for packaging material made for the locally produced vegetables. In the first step, we developed a pre-treatment process to obtain a hydrolysate, which contained 34 g L-1 sugars and 0.7 g L-1 total Kjeldahl nitrogen. This hydrolysate was used as fermentation substrate for three PHB-producing strains. Cupriavidus necator DSM 428 reached a dry biomass concentration of 11.3 g L-1 with a PHB content of 66 % in dry mass within 5 days. C. necator DSM 531 yielded 3.5 g L-1 dry biomass containing 46 % PHB within the same period. C. necator DSM 545 was superior over the other two in that 14.0 g L-1 of biomass containing 78 % PHB after only 3 days were obtained. These results show that even within the same species, the productivities on natural substrates are very different. The produced polymers were extracted using chloroform, and several thermo-physical parameters are in good accordance with published data. Overall, our holistic approach and the encouraging results prove that chicory roots are a viable fermentation substrate for PHB-production.This work was conducted as a part of the LEAD-ERA Project CARBIO, which was financed by the Basque Goverment and co-financed by the European Regional Development Fund (ERDF) of the European Union

Macromolecular diffusion in crowded media beyond the hard-sphere model

The effect of macromolecular crowding on diffusion beyond the hard-core sphere model is studied. A new coarse-grained model is presented, the Chain Entanglement Softened Potential (CESP) model, which takes into account the macromolecular flexibility and chain entanglement. The CESP model uses a shoulder-shaped interaction potential that is implemented in the Brownian Dynamics (BD) computations. The interaction potential contains only one parameter associated with the chain entanglement energetic cost (Ur). The hydrodynamic interactions are included in the BD computations via Tokuyama mean-field equations. The model is used to analyze the diffusion of a streptavidin protein among different sized dextran obstacles. For this system, Ur is obtained by fitting the streptavidin experimental long-time diffusion coefficient Dlong versus the macromolecular concentration for D50 (indicating their molecular weight in kg mol-1) dextran obstacles. The obtained Dlong values show better quantitative agreement with experiments than those obtained with hard-core spheres. Moreover, once parametrized, the CESP model is also able to quantitatively predict Dlong and the anomalous exponent (a) for streptavidin diffusion among D10, D400 and D700 dextran obstacles. Dlong, the short-time diffusion coefficient (Dshort) and a are obtained from the BD simulations by using a new empirical expression, able to describe the full temporal evolution of the diffusion coefficient

Positioning Axes of Sustainable Tourist Destinations: The Case of Aragón

The purpose of this research is to determine the optimal positioning strategies of Aragón as a sustainable tourist destination. An exploratory research is carried out based on the analysis of statistical information sources, the identification of global and multisectoral macro-trends with direct impact on the evolution of the tourist sector, and the use of the qualitative technique of the focus group. The main and secondary axes to provide a basis for the positioning strategy of the autonomous community are presented as a resul

Brownian dynamics computational model of protein diffusion in crowded media with dextran macromolecules as obstacles

The high concentration of macromolecules (i.e., macromolecular crowding) in cellular environments leads to large quantitative effects on the dynamic and equilibrium biological properties. These effects have been experimentally studied using inert macromolecules to mimic a realistic cellular medium. In this paper, two different experimental in vitro systems of diffusing proteins which use dextran macromolecules as obstacles are computationally analyzed. A new model for dextran macromolecules based on effective radii accounting for macromolecular compression induced by crowding is proposed. The obtained results for the diffusion coefficient and the anomalous diffusion exponent exhibit good qualitative and generally good quantitative agreement with experiments. Volume fraction and hydrodynamic interactions are found to be crucial to describe the diffusion coefficient decrease in crowded media. However, no significant influence of the hydrodynamic interactions in the anomalous diffusion exponent is found