Derivations of forms along a map: the framework for time-dependent second-order equations

AbstractA comprehensive theory is presented concerning derivations of scalar and vector-valued forms along the projection π : R × TM → R × M. It is the continuation of previous work on derivations of forms along the tangent bundle projection and is prompted by the need for a scheme which is adapted to the study of time-dependent second-order equations. The overall structure of the theory closely follows the pattern of this preceding work, but there are many features which are certainly not trivial transcripts of the time-independent situation. As before, a crucial ingredient in the classification of derivations is a non-linear connection on the bundle π. In the presence of a given second-order system, such a connection is canonically defined and gives rise to two important operations: the dynamical covariant derivative, which is a derivation of degree 0, and the Jacobi endomorphism, which is a type (1, 1) tensor field along π. The theory is developed in such a way that all results readily apply to the more general situation of a bundle π : J1 E → E, where E is fibred over R, but need not be the trivial fibration R × M → R

Configuration of a reference scenario for the land use modelling platform

The definition of the Reference Scenario, given in the Energy Trends to 2030 publication by DG ENER (2009 update ), assumes full implementation of the Climate and Energy package. The legislation included within the Climate and Energy Package is reflective of the legally binding targets to ensure that the EU meets its climate and energy targets for 2020. This scenario assumes that national targets under the Renewables directive (2009/28/EC) and the GHG Effort-sharing decision (2009/406/EC) are achieved. The Reference scenario is one of three energy trends scenarios, used so far for the Energy 2050 Roadmap Impact assessment . The scenarios are derived with the PRIMES model by a consortium led by the National Technical University of Athens (E3MLab). The PRIMES model is key to the definition of the scenarios because of its energy focus. The Reference Scenario itself is derived within PRIMES and is supported by other specialised models downstream. The purpose of this document is to describe how the LUMP was configured in order to be consistent with the PRIMES and other upstream models within the integrated modelling chain, including the incorporation of the legally binding objectives, directives and guidelines. In order to be coherent with the IA accompanying the Communication on the Energy Roadmap 2050, new policies adopted up until March 2010 were implemented in so far as possible. The implementation has not yet been finalized and this document will be refreshed and re-distributed in its final form once the Reference Scenario has been fully configured.JRC.H.8-Sustainability Assessmen

Finite size effects on transport coefficients for models of atomic wires coupled to phonons

We consider models of quasi-1-d, planar atomic wires consisting of several, laterally coupled rows of atoms, with mutually non-interacting electrons. This electronic wire system is coupled to phonons, corresponding, e.g., to some substrate. We aim at computing diffusion coefficients in dependence on the wire widths and the lateral coupling. To this end we firstly construct a numerically manageable linear collision term for the dynamics of the electronic occupation numbers by following a certain projection operator approach. By means of this collision term we set up a linear Boltzmann equation. A formula for extracting diffusion coefficients from such Boltzmann equations is given. We find in the regime of a few atomic rows and intermediate lateral coupling a significant and non-trivial dependence of the diffusion coefficient on both, the width and the lateral coupling. These results, in principle, suggest the possible applicability of such atomic wires as electronic devices, such as, e.g., switches.Comment: 9 pages, 5 figures, accepted for publication in Eur. Phys. J.

Recombinant expression of the voltage-dependent anion channel enhances the transfer of Ca2+ microdomains to mitochondria

Although the physiological relevance of mitochondrial Ca2+ homeostasis is widely accepted, no information is yet available on the molecular identity of the proteins involved in this process. Here we analyzed the role of the voltage-dependent anion channel (VDAC) of the outer mitochondrial membrane in the transmission of Ca2+ signals between the ER and mitochondria by measuring cytosolic and organelle [Ca2+] with targeted aequorins and Ca2+-sensitive GFPs. In HeLa cells and skeletal myotubes, the transient expression of VDAC enhanced the amplitude of the agonist-dependent increases in mitochondrial matrix Ca2+ concentration by allowing the fast diffusion of Ca2+ from ER release sites to the inner mitochondrial membrane. Indeed, high speed imaging of mitochondrial and cytosolic [Ca2+] changes showed that the delay between the rises occurring in the two compartments is significantly shorter in VDAC-overexpressing cells. As to the functional consequences, VDAC-overexpressing cells are more susceptible to ceramide-induced cell death, thus confirming that mitochondrial Ca2+ uptake plays a key role in the process of apoptosis. These results reveal a novel function for the widely expressed VDAC channel, identifying it as a molecular component of the routes for Ca2+ transport across the mitochondrial membranes

An assessment of dedicated energy crops in Europe under the EU Energy Reference Scenario 2013. Application of the LUISA modelling platform - Updated Configuration 2014

This report presents a comprehensive analysis of dedicated energy crops (ENCR) performed with the LUISA (Land Use-based Integrated Sustainability Assessment) modelling platform across Europe between 2020 and 2050. LUISA is configured in compliance with the “EU Energy, Transport and GHG emissions trends until 2050” document in order to ensure that the EU meet its climate and energy targets up to 2050 (EU Reference Scenario 2013, updated LUISA configuration 2014). The spatial modelling of ENCR in LUISA requires determining a set of elements such as the land demand, availability and suitability of the land, and other land categories for the ENCR cultivation. Thus, the assessment is focused on the following steps: 1) Land accounts and dominant land use/cover flows for the expansion of energy crops at European scale, 2) A suitability analysis of the land dedicated to these crops based on suitability maps, 3) Recuperation of degraded and contaminated lands for energy purpose, 4) A detailed regional analysis per each Member State (factsheets) with a summary of the main important findings, and 5) Evaluation of energy crops’ impacts on a selection of environmental indicators (provision of ecosystem services). In LUISA, the displacement and cultivation of crops solely dedicated to energy production takes place on a specific land-use class named ‘energy crop’ (ENCR), which competes in particular with the demand for others land-uses, such as for food, feed and forest. The amount of ENCR reaches about 13,549 kha in 2050 that represents, on average, 3.6% of Europe’s total available land. This expansion occurs mainly at expenses of land for food and feed (90%). Forest and natural land (9% and 1%,) represent respectively the second and third land flows towards ENCR among total land-use changes (with these flows represented respectively 9 and 1% of all land use changes). As result of this land competition, there is an increasing shift of food and feed crops towards low quality land, due not only to the ENCR expansion but also to the growth of residential and economic-driven land uses. It should also be noted that intensive agriculture practices for ENCR production might have some negative impacts on soil, water, biodiversity, amongst others. Owing to this potential impacts, the analysis performed on the supply of a set of ecosystem services identifies some services more sensitive than others to ENCR growth. In particular, pollination potential, habitat quality for birds and also the Green-Infrastructure network are expected to decrease due to ENCR growth, while patterns for recreational opportunities and water retention services are less evident.JRC.H.8-Sustainability Assessmen

European landscape changes between 2010 and 2050 under the EU Reference Scenario: EU Reference Scenario 2013 LUISA platform – Updated Configuration 2014

The ‘Land-Use-based Integrated Sustainability Assessment’ modelling platform (LUISA) is primarily used for the ex-ante evaluation of EC policies that have a direct or indirect territorial impact. It is based on the concept of ‘land function’ for cross-sector integration and for the representation of complex system dynamics. Beyond a traditional land use model, LUISA adopts a new approach towards activity-based modelling based upon the endogenous dynamic allocation of population, services and activities. LUISA has been applied to address the competition for land arising from the energy, transport and climate dimensions of EU policies and configured according to the EU Energy Reference scenario 2013 (updated configuration 2014) to produce high-resolution land use/cover projections up to 2050 and a related series of thematic indicators. This report describes the stocks and the main land cover/use flows (LCF) taking place in Europe in the period 2010-2050 and the processes that cause those flows, thus providing insight on how the European landscape might change if the future happens according to a reference scenario consistent with settings (economic and demographic in particular) and policies in place in 2013 (hence including in particular the 2020 renewable energy targets). Main findings: • The extent of the land for housing and leisure (urban) and industrial/commercial and services (ICS) increases, while the area of agriculture, forest and natural land decreases; • Urban and industrial land are expected to represent the highest share of net formation as % of the initial year (2010); • Energy crops appear in the model as of 2020 and are expected to reach 135,479 km2 across Europe in 2050; • Energy crops become the second most important land transformation in Europe (17%); approximately 90 % of the land consumed for energy purposes comes from land for food and feed, followed by forest and natural land; • While a large proportion of land dedicated to food and feed crops is expected to be converted into dedicated energy crops, the net land losses are very small as a results of the conversion from forest land into food and feed production; • New forest and natural land compensate in some way for quantity of losses or consumption by other uses; however the high value of the turnover indicator, reveal that those land-uses are unstable and vulnerable to the fast changes driven by economic development and climate changes, thus compromising the biodiversity and habitat conservation status; • The conversion between farming types represent 35% over the total land changes between 2010 and 2050; The results show the loss of natural and agricultural land because of ever-ongoing urbanisation and industrialization processes. The loss of natural and agricultural land for food production is even larger because of the advent of energy crops production incited by shifts in the European Energy supply system.JRC.H.8-Sustainability Assessmen

Direct and Indirect Land Use Impacts of the EU Cohesion Policy. Assessment with the Land Use Modelling Platform

The Cohesion policy for the programming period 2014-2020 is analyzed in terms of its likely land use and environmental impacts using the Land Use Modelling Platform (LUMP). This report describes in detail the process and the methodology by which the ex-ante impact assessment was made, and presents the results for Austria, Czech Republic, Germany, and Poland. The modelling approach can provide insights on the trade-offs between economic growth, investment policies (such as the Cohesion policy), and land use and the environment. In addition, ways to mitigate potentially negative land use and environmental impacts were explored. The future development of the LUMP is discussed in view of planned future work.JRC.H.8-Sustainability Assessmen