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[en] Non-equilibrium systems are characterized by a rich variety of dynamical behaviors, which may sensitively depend on control parameters. Here, we investigate and provide a quantitative analysis of the role of disorder on the transitions between different dynamical regimes in extended heterogeneous systems of excitable and passive cells, induced by varying the strength of the coupling between cells. The random distribution of passive cells provides a quenched disorder in important biological contexts, such as the appearance of contractions in the pregnant uterus. We observe a large variability between different realizations of the disorder (replicas) in a lattice of excitable cells, each cell being coupled to a random number of passive cells. The statistics of these large disorder-induced fluctuations are related to the properties of the coarse-grained distribution of passive cells, in particular, to its extreme values. We show that these fluctuations can be characterized by a simple scaling relation, involving the strength of the coupling between excitable cells, the mean passive cell density and the logarithm of the system size. Our results provide a quantitative understanding of the important effect of a quenched disorder in the transition between dynamical regimes in extended dynamical systems. (paper)
[en] This guide, intended for elected officials responsible for climate-energy issues, will allow to better understand the major current and future energy issues as well as the skills and role that communities have to play. It also aims to provide the operational elements to set up a transversal policy aimed at accelerating the energy transition at the local level and benefiting all citizens. This guide proposes to the elected official the keys to acting on the following themes: - Develop and implement a public energy policy in its territory with the right planning, monitoring and animation tools; - Control the energy consumption of its heritage and its territory (public buildings, lighting, mobility, etc.); - Accelerate the energy renovation of housing and fight against energy insecurity; - Support the development of all renewable and recovery energies (biomass, geothermal energy, waste heat, wind, photovoltaic, biogas, etc.) as well as hydrogen; - Putting its energy networks at the service of the energy transition (electricity, gas, heat).
[fr]Ce guide, destine aux elus charges des questions climat-energie, vous permettra de mieux apprehender les grands enjeux energetiques actuels et a venir de meme que les competences et le role que les collectivites ont a jouer. Il a egalement comme objectif d'apporter les elements operationnels pour mettre en place une politique transversale visant a accelerer la transition energetique au niveau local et en faire beneficier l'ensemble des citoyens. Vous trouverez ainsi dans ce guide les cles pour agir sur les thematiques suivantes: - Elaborer et mettre en oeuvre une politique publique energetique sur son territoire avec les bons outils de planification, de suivi et d'animation; - Maitriser les consommations d'energie de son patrimoine et de son territoire (batiments publics, eclairage, mobilites...); - Accelerer la renovation energetique des logements et lutter contre la precarite energetique; - Accompagner le developpement de toutes les energies renouvelables et de recuperation (biomasse, geothermie, chaleur fatale, eolien, photovoltaique, biogaz...) ainsi que l'hydrogene; - Mettre ses reseaux d'energie au service de la transition energetique (electricite, gaz, chaleur). Elabore en partenariat avec la Banque des territoires - Caisse des Depots, ce guide est le fruit de l'expertise d'Amorce au contact de l'ensemble des collectivites et des acteurs impliques sur le territoire dans le domaine de l'energie.
[en] PET acquisition requires several minutes which can lead to respiratory motion blurring, to increase partial volume effect and SUV under-estimation. To avoid these artifacts, conventional 10-min phase-based respiratory gating (PBRG) can be performed but is time-consuming and difficult with a non-compliant patient. We evaluated an automatic amplitude-based gating method (AABG) which keeps 35% of the counts at the end of expiration to minimize respiratory motion. We estimated the impact of AABG on upper abdominal lesion detectability, quantification and patient management. Methods: We consecutively included 31 patients (82 hepatic and 25 perihepatic known lesions). Each patient underwent 3 acquisitions on a Siemens Biograph mCT (4 rings and time-of-flight): a standard free-breathing whole-body (SWB, 5–7 steps/2.5 min per step, 3.3 ± 0.4 MBq/kg of 18F-FDG), a 10-min PBRG with six bins and a 5-min AABG method. All gated acquisitions were performed with an ANZAI respiratory gating system. SUV_m_a_x and target to background ratio (TBR, defined as the maximum SUV of the lesion divided by the mean SUV of a region of interest drawn in healthy liver) were compared. Results: All 94 lesions in SWB images were detected in the gated images. 10-min PBRG and 5-min AABG acquisitions respectively revealed 9 and 13 new lesions and relocated 7 and 8 lesions. Four lesions revealed by 5-min AABG were missed by 10-min PBRG in 3 non-compliant patients. Both gated methods failed to relocate 2 lesions seen on SWB acquisition. Compared to SWB, TBR increased significantly with 10-min PBRG and with 5-min AABG (respectively 41 ± 59%, p = 4.10–3 and 66 ± 75%, p = 6.10–5) whereas SUV_m_a_x did not (respectively 14 ± 43%, p = 0.29 with 10-min PBRG, and 24 ± 46%, p = 0.11 with 5-min AABG). Conclusion: The AABG is a fast and a user-friendly respiratory gating method to increase detectability and quantification of upper abdominal lesions compared to the conventional PBRG procedure and the SWB acquisition
[en] In the first version, this report first introduces the challenge of climate change and the emergence of the commitment of local communities. It describes how a community could better consume, produce and distribute energy, how it could better organise transports and land planning, and intervene on building quality, how it can inform inhabitants and incite individuals and enterprises, how it can struggle against climate change, how energy actions can be financed. It also recalls European objectives and proposes sheets of presentation of examples. The second report contains similar information, but also addresses issues related to the definition of a local energy-climate policy: to perform and to share a diagnosis, to define ambitious objectives through a participative operational approach, to implement structuring actions for such a policy, to address issues related to assessment and follow-up, and to finance these actions. Several examples are as well presented.
[en] A first set of contributions presents heat networks as a tool at the service of local communities for a successful energy transition. The second set discusses the role of these networks as they are perceived by project holders in terms of economic attractiveness for a community and a territory. The third set discusses how to ease the creation or the development of a heat network. The fourth set presents heat networks as an efficient, ecological and innovative tool to the massification of renewable and recovery energies. Experimentations are then reported and commented (experiment in a company, user expectations, urban heat network, low temperature solutions with solar thermal, geothermal or heat recovery, high temperature solutions). The next set addresses financial tools from the point of view of users and of financing actors. Some specific contributions address the individual and collective housing sector (stakes, design, support, roles of local communities and available tools), stakes of the domestic wood heating sector, the role of industrial solar heat, waste energy, stakes of deep geothermal energy, the key factors for a successful wood energy project, and the production of renewable heat from renewable gases.
[en] This huge publication contains contributions and sessions of a conference which addressed the following issues: new abilities and professions in the energy sector, perspectives for local and energy policies and for the society after the COP21 and the role of local communities (tools and actions, education, development of cold networks, and so on), a discussion about what happened during the past year with notably the French law for energy transition and a green growth, an overview of the GRHYD demonstrator (the first Power-to-Gas demonstrator in France), how to finance energy transition, how to shift towards a societal transition, sustainable mobility (a city without car made by its inhabitants), urban agriculture as a lever for action for energy transition, the role of citizen in tomorrow's energy, the post-COP21 European, national and local agenda, energy transition and jobs. Workshops and forums related to various aspects related to these issues are also reported
[en] Single crystals of LuAP co-doped with divalent (Ca2+) and tetravalent (Hf4+, Zr4+, Si4+) ions were grown from the melt using Bridgman method. Characterization is done in terms of optical absorption spectra in as-grown and UV or gamma-ray irradiated crystals
[en] The oldest (2012) of two reports proposes a definition and some key figures regarding heat networks. Then, it outlines the strong national and European dynamics, presents heat networks as an unavoidable tool of territorial energy policies, describes the process of development, creation and exploitation of a heat network, and how to manage and extend such a network. It also presents cold networks, discusses the various aspects of the relationships with subscribers and users, and discusses the relationship between land planning and heat networks. The most recent report (2017), after the same kind of presentation of heat networks, of their key figures and of their role in energy policy, discusses their strategic role for the community of the development of heat or cold networks, discusses how to assess the opportunity of their development on a territory, describes how to implement a heat or cold network project, how to manage and extend an existing heat network, and also how to manage relationships with subscribers and users.
[en] After a justification of the interest of local investments in renewable energy projects, this report defines what could be these projects in terms of nature and of project holders. It outlines that local investments are now easier thanks to recent regulatory and legal texts (law for energy transition, easier crowd-funding). It presents the different legal frameworks and financing modes, and discusses the different financial stakes associated with the different phases of the project (identification, exploration, development, financing and construction, exploitation). It also identifies the best moments for investments in such projects.
[en] Performance properties of LuAP, a material of highly promising potential for future PET scanners, are presented, as they relate to crystal growth and composition. The light yield measured in 2x2x10 mm3 elements with 0.4-0.5% Ce and cut from large size crystals (100 mm long and 15 mm in diameter) grown by the Bridgman technique is improved to 40% LSO. The ratio between light yield measured in vertical and horizontal arrangements in the best crystals is near 90%. The role of chemical purity in respect to divalent impurities is studied