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The energy challenge is a complex issue that EU is facing. A sustainable, safe and competitive energy supply and climate change mitigation are nowadays key priorities of EU energy policy and a need for each EU Member State. Sustainable energy development at the regional level is a multiple and complex activity, involving various stakeholders and different measures. Three main thematic pillars, policy making, energy market and community involvement, have been identified as crucial in order to implement effective and feasible policy and measures at the regional scale. In this framework, the initial assessment of regional energy systems is an essential step to set up customized sustainable energy strategies. In the framework of the INTERREG IVC RENERGY project a structured methodology for the initial assessment of local communities (Self-Assessment -SAA) was defined and applied to the analysis of the partners' communities located in nine European Countries (Lithuania, Denmark, Italy, Portugal, United Kingdom, Germany, Austria, Hungary and Romania) in order to outline the status of local energy infrastructures, renewable and energy efficiency potentials and to highlight the key issues to be exploited in the local implementation plans. The holistic approach of the SAA methodology is aimed at characterising the energy systems in terms of policy background, energy uses and infrastructures as well as market behaviour and community attitude for sustainable development, valorising the interrelationships among the project thematic pillars.

Farming of shellfish and seaweeds is a tested tool for mitigating eutrophication consequences in coastal environments, however as many other marine economic activities it should be a subject of marine spatial planning for designating suitable sites. The present study proposes site selection framework for provisional zebra mussel farming in a eutrophic lagoon ecosystem, aimed primarily at remediation purposes. GIS-based multi-criteria approach was applied, combining data from empirical maps, numerical models and remote sensing to estimate suitability parameters. Site selection and prioritisation of suitable areas considered 15 environmental and socio-economic criteria, which contributed to 4 optimisation models (settlement, growth and survival of mussels, environmental and socio-economic) and 3 predefined scenarios representing provisional goals of mussel cultivation: spat production, biomass production and bioremediation. The relative importance of each criterion was assessed utilizing the Analytical Hierarchy Process. Site suitability index was calculated and the final result of the site selection analysis was summarized for 3 scenarios and overall suitability map. Four suitability classes (unsuitable, least, moderately and most suitable) were applied, and 3 most suitable zones for provisional zebra mussel cultivation with 12 candidate sites were selected accordingly. The integrated approach presented in this study can be adjusted for designating zebra mussel farming sites in other estuarine lagoon ecosystems, or cultivation of other mussel species for bioremediation purposes. The analytical framework and the workflow designed in this study are also adoptable for addressing other aquaculture-related spatial planning issues.

Dispersed transient absorption spectra collected at variable excitation intensities in combination with time-resolved signals were used to explore the underlying connectivity of the electronic excited-state manifold of the carotenoid rhodopin glucoside in the light-harvesting 2 complex isolated from Rhodopseudomonas acidophila. We find that the S state, which was recently identified as an excited state in carotenoids bound in bacterial light-harvesting complexes, exhibits a different response to the increase of excitation intensity than the S(1) state, which suggests that the models used so far to describe the excited states of carotenoids are incomplete. We propose two new models that can describe both the time-resolved and the intensity-dependent data; the first postulates that S(1) and S* are not populated in parallel after the decay of the initially excited S(2) state but instead result from the excitation of distinct ground-state subpopulations. The second model introduces a resonantly enhanced light-induced transition during excitation, which promotes population to higher-lying excited states that favors the formation of S* over S(1). Multiwavelength target analysis of the time-resolved and excitation-intensity dependence measurements were used to characterize the involved states and their responses. We show that both proposed models adequately fit the measured data, although it is not possible to determine which model is most apt. The physical origins and implications of both models are explored.

The Authors tested a new mini-baler system designed for the recovery of pruning residues in vineyards inaccessible to conventional tractors. Under these conditions, growers manually take the residues to the field edge and burn them there. Such practice is expensive, and generates substantial emissions. Use of the new mini-baler system would substitute burning, with significant advantages on air quality and landscape amenity. The system works well, but productivity is low (mean 0.38t per scheduled machine hour) and baling cost still too high (mean 80EURt-1). Productivity can be increased and cost decreased through a better preparation of the residues before collection. Farm use of the baled product may dramatically increase value recovery and is facilitated by the availability of newly designed boilers. The versatility and the small purchase cost of the mini-baler makes it an ideal machine for those cases where labour cost is low and investment capacity is limited. © 2014 Elsevier B.V.

The functionalized soluble poly(p-phenylene vinylene) derivative bearing polar molecules (NLO-PPV) was designed and synthesized to investigate effects of molecular orientation in single-layer polymer photovoltaic devices. The active molecule is the 4-(N-butyl-N-2-hydroxyethyl)-1-nitro-benzene group on the copolymer. The grafting of the molecule with a donor/transmitter/acceptor structure, possessing a large ground state dipole moment, enables their orientation by a DC-electric field. An internal electric field in such layer facilitates exciton dissociation and improves charge transport. We report increase of the external quantum efficiency by a factor of 1.5 to 2 upon orientation. The associated effects on the carrier injection and transport depending on the orientation direction were evidenced.

We have compared picosecond fluorescence decay kinetics for stacked and unstacked photosystem II membranes in order to evaluate the efficiency of excitation energy transfer between the neighboring layers. The measured kinetics were analyzed in terms of a recently developed fluctuating antenna model that provides information about the dimensionality of the studied system. Independently of the stacking state, all preparations exhibited virtually the same value of the apparent dimensionality, d = 1.6. Thus, we conclude that membrane stacking does not affect the efficiency of the delivery of excitation energy toward the reaction centers but ensures a more compact organization of the thylakoid membranes within the chloroplast and separation of photosystems I and II.

Complex multi-exponential fluorescence decay kinetics observed in various photosynthetic systems like photosystem II (PSII) have often been explained by the reversible quenching mechanism of the charge separation taking place in the reaction center (RC) of PSII. However, this description does not account for the intrinsic dynamic disorder of the light-harvesting proteins as well as their fluctuating dislocations within the antenna, which also facilitate the repair of RCs, state transitions, and the process of non-photochemical quenching. Since dynamic fluctuations result in varying connectivity between pigment-protein complexes, they can also lead to non-exponential excitation decay kinetics. Based on this presumption, we have recently proposed a simple conceptual model describing excitation diffusion in a continuous medium and accounting for possible variations of the excitation transfer pathways. In the current work, this model is further developed and then applied to describe fluorescence kinetics originating from very diverse antenna systems, ranging from PSII of various sizes to LHCII aggregates and even the entire thylakoid membrane. In all cases, complex multi-exponential fluorescence kinetics are perfectly reproduced on the entire relevant time scale without assuming any radical pair equilibration at the side of the excitation quencher, but using just a few parameters reflecting the mean excitation energy transfer rate as well as the overall average organization of the photosynthetic antenna.

Dispersed multipump-probe (PPP) spectroscopy was used to explore the role of saturation, annihilation, and structured pulses in recent coherent control experiments on the light-harvesting 2 complex from Rhodopseudomonas acidophila (Herek et al. Nature 2002, 417, 533). We discuss the complimentary aspects between the PPP technique and coherent control studies, in particular the ability to dissect complicated pulse structures and the utility in exploring incoherent mechanisms. With the aid of a simple multistate model involving only population dynamics, we illustrate how the optimized structured pulses may be explained in terms of an interplay between excited-state populations, saturation, and annihilation. Furthermore, we discuss the experimental conditions that are required for incoherent effects to contribute to control experimental signals, with particular emphasis on pulse intensities, and show that the optimization of a ratio of conservative signals (i.e., not modulated by external dynamics) is required to exclude saturation effects from coherent control studies.