Evaluation of Environmental Accounting Methodologies for the assessment of global environmental impacts of traded goods and services.

Environmental accounting methods (EAM) are currently getting a strong interest from political entities, multinational corporations and citizens. EAMs are applied to a large range of socio-techno-economic activities for monitoring and managing their environmental performance over time: at macro-level to implement the environmental pillar of sustainable development, at meso-level for companies reporting and at micro-level for comparing the environmental footprints of products. IMEA project (IMports Environmental Accounting) is a SKEP-Era-net project (Scientific Knowledge for Environmental Protection) aiming at assessing the potential of EAMs to consider the challenges from globalization and environmental impacts linked to international trade. It was lead by MINES ParisTech/ARMINES with partners from the Institute of Social Ecology, Vienna, TNO, University of Oulu, and VITO, carried out between June 2008 and September 2009. The global aim of IMEA is to provide elements to answer the following question: "Does a given EAM meet societal expectations and how does it cope with new challenges from globalization?". IMEA has focused on the analysis of these challenges based on what EAMs "are", "how" they function and the use of their results in decision-making by the means of an archetypical workflow and an analytical framework. Based on this comprehensive analytical framework, the following EAMs. have been assessed in detail: Life Cycle Assessment, Economy-Wide Material Flow Analysis, Physical Input Output Tables, Environmentally Extended Input-Output Analysis, land use indicators like the Human Appropriation of Net Primary Production, the Actual Land Demand or the Ecological Footprint, and the Water Footprint

Assessing Regional Sustainability with the EPSILON Project

http://www.smia.info/files/eh94g6x4.f1_fr-1254.pdfInternational audienceThe EPSILON project (Environmental Policy via Sustainability Indicators On a European-wide level --2002-2005) is delivering a GIS integrated computerized model for benchmarking European regions through an aggregation of indicators represented on sustainability maps. Assessing sustainability within the EPSILON project has been addressed over four spheres/pillars: the environmental, the economic, the social and the institutional dimension as defined by the UN Commission on Sustainable Development. A coherent objective based structure has been defined relying strongly on the analytical DPSIR framework (Driving-Forces, Pressures, State, Impact and Response model from the European Environmental Agency). Such structure has been defined through a relevant definition of Indicators, sub-themes, themes and pillars for which maps at national level over 15 European countries are provided. Regional maps are also provided at regional levels (NUTS II and NUTS III levels). These results should not be considered as absolute figures but rather as an attempt of a relative sustainability assessment. Such regional sustainability assessment illustrates the interest to move down from a national assessment to a more local level by revealing higher data dispersion and detecting for example specific environmental issues, which would have been levelled otherwise at national scale

DFT study of the solubility of hydrogen and carbon in Ni3Nb-D0a and Ni3Nb-D022 systems

The influence of the local environment on C and H atoms was investigated in Ni3Nb-D0a (space group 59) and Ni3Nb-D022 (space group 139) crystals. The interstitial positions of these atoms and their solubility energies were studied by analyzing the results of first-principles calculations based on density functional theory. The results were compared with those obtained in pure and Nb alloyed fcc Ni. For C atoms, several possible interstitial sites were found, but only one (per structure) is slightly more stable than the others: the 4d sites for D0a and the 4c sites for D022. The C atom is slightly soluble and its solubility energy is equivalent in the two intermetallic structures: approximately equal to 1.06 eV, which is significantly larger than in fcc Ni (0.55 eV). In the case of hydrogen, other interstitial sites were identified: the 4e positions for both D0a and D022. The solubility energy in D0a (approximately 0.12 eV, without the zero-point energy correction) was found to be smaller than that in D022 (0.17 eV) but larger than that in nickel (0.09 eV). With the zero-point energy correction, the solubility in both Ni3Nb alloys is therefore equivalent. These results were finally used to assess the fraction of light elements in Ni3Nb relative to that in fcc Ni and that in Ni doped Nb

Effect of trapping and temperature on the hydrogen embrittlement susceptibility of alloy 718

Ni-based alloy 718 is widely used to manufacture structural components in the aeronautic and nuclear industries. Numerous studies have shown that alloy 718 may be sensitive to hydrogen embrittlement. In the present study, the susceptibilities of three distinct metallurgical states of alloy 718 to hydrogen embrittlement were investigated to identify both the effect of hydrogen trapping on hydrogen embrittlement and the role of temperature in the hydrogen-trapping mechanism. Cathodic charging in a molten salt bath was used to saturate the different hydrogen traps of each metallurgical state. Tensile tests at different temperatures and different strain rates were carried out to study the effect of hydrogen on mechanical properties and failure modes, in combination with hydrogen content measurements. The results demonstrated that Ni-based superalloy 718 was strongly susceptible to hydrogen embrittlement between 25 °C and 300 °C, and highlighted the dominant roles played by the hydrogen solubility and the hydrogen trapping on mechanical behavior and fracture modes

Regioselective Synthesis of Indene from 3-Aryl Propargylic gem -Dipivalates Catalyzed by N -Heterocyclic Carbene Gold(I) Complexes

International audience1-Aryl-3,3-bis(pivaloyloxy)propynes can be converted in good to high yields into either 1,3-or 1,2-bis(pivaloyloxy)indenes, depending on the N-heterocyclic carbene (NHC) gold(I) hexafluoroantimonate catalyst used. Almost exclusive formation of 1,3-di(oxycarbonyl)indene derivatives was achieved with cationic gold complexes containing the embracing N,N'-1,3-bis(9-butylfluorenyl)benzimidazolylidene ligand (nBu FNHC). The regioselective issue of the reaction was rationalized by the specific spatial distribution of the steric bulk in the nBu FNHC ligand. In contrast, only modest selectivities in favor of 1,2-disubstituted indenes were observed with more classical NHC gold complexes, the best selectivity being then obtained with N,N'-1,3-bis(2,6-diisopropylphenyl)-4,5-dihydroimidazolylidene gold chloride (SIPrAuCl) as precatalyst

Plk4 Regulates Centriole Asymmetry and Spindle Orientation in Neural Stem Cells

Defects in mitotic spindle orientation (MSO) disrupt the organization of stem cell niches impacting tissue morphogenesis and homeostasis. Mutations in centrosome genes reduce MSO fidelity, leading to tissue dysplasia and causing several diseases such as microcephaly, dwarfism, and cancer. Whether these mutations perturb spindle orientation solely by affecting astral microtubule nucleation or whether centrosome proteins have more direct functions in regulatingMSO is unknown. To investigate this question, we analyzed the consequences of deregulating Plk4 (the master centriole duplication kinase) activity in Drosophila asymmetrically dividing neural stem cells. We found that Plk4 functions upstream of MSO control, orchestrating centriole symmetry breaking and consequently centrosome positioning. Mechanistically, we show that Plk4 acts through Spd2 phosphorylation, which induces centriole release from the apical cortex. Overall, this work not only reveals a role for Plk4 in regulating centrosome function but also links the centrosome biogenesis machinery with the MSO apparatus.ERC starting grant CentroStemCancer [242598]; Institut Curie; CNRS; NCI [P30CA23074]; NIGMS [R01 GM110166, GM126035]; FRM; IC; FRM installation grant; ATIP grantOpen access articleThis item from the UA Faculty Publications collection is made available by the University of Arizona with support from the University of Arizona Libraries. If you have questions, please contact us at [email protected]

Does the disturbance hypothesis explain the biomass increase in basin-wide Amazon forest plot data?

Positive aboveground biomass trends have been reported from old-growth forests across the Amazon basin and hypothesized to reflect a large-scale response to exterior forcing. The result could, however, be an artefact due to a sampling bias induced by the nature of forest growth dynamics. Here, we characterize statistically the disturbance process in Amazon old-growth forests as recorded in 135 forest plots of the RAINFOR network up to 2006, and other independent research programmes, and explore the consequences of sampling artefacts using a data-based stochastic simulator. Over the observed range of annual aboveground biomass losses, standard statistical tests show that the distribution of biomass losses through mortality follow an exponential or near-identical Weibull probability distribution and not a power law as assumed by others. The simulator was parameterized using both an exponential disturbance probability distribution as well as a mixed exponential–power law distribution to account for potential large-scale blowdown events. In both cases, sampling biases turn out to be too small to explain the gains detected by the extended RAINFOR plot network. This result lends further support to the notion that currently observed biomass gains for intact forests across the Amazon are actually occurring over large scales at the current time, presumably as a response to climate change

The endogenous retrovirus ENS-1 provides active binding sites for transcription factors in embryonic stem cells that specify extra embryonic tissue

<p>Abstract</p> <p>Background</p> <p>Long terminal repeats (LTR) from endogenous retroviruses (ERV) are source of binding sites for transcription factors which affect the host regulatory networks in different cell types, including pluripotent cells. The embryonic epiblast is made of pluripotent cells that are subjected to opposite transcriptional regulatory networks to give rise to distinct embryonic and extraembryonic lineages. To assess the transcriptional contribution of ERV to early developmental processes, we have characterized <it>in vitro </it>and <it>in vivo </it>the regulation of ENS-1, a host adopted and developmentally regulated ERV that is expressed in chick embryonic stem cells.</p> <p>Results</p> <p>We show that <it>Ens-1 </it>LTR activity is controlled by two transcriptional pathways that drive pluripotent cells to alternative developmental fates. Indeed, both Nanog that maintains pluripotency and Gata4 that induces differentiation toward extraembryonic endoderm independently activate the LTR. Ets coactivators are required to support Gata factors' activity thus preventing inappropriate activation before epigenetic silencing occurs during differentiation. Consistent with their expression patterns during chick embryonic development, Gata4, Nanog and Ets1 are recruited on the LTR in embryonic stem cells; in the epiblast the complementary expression of Nanog and Gata/Ets correlates with the <it>Ens-1 </it>gene expression pattern; and Ens-1 transcripts are also detected in the hypoblast, an extraembryonic tissue expressing Gata4 and Ets2, but not Nanog. Accordingly, over expression of Gata4 in embryos induces an ectopic expression of <it>Ens-1</it>.</p> <p>Conclusion</p> <p>Our results show that <it>Ens-1 </it>LTR have co-opted conditions required for the emergence of extraembryonic tissues from pluripotent epiblasts cells. By providing pluripotent cells with intact binding sites for Gata, Nanog, or both, <it>Ens-1 </it>LTR may promote distinct transcriptional networks in embryonic stem cells subpopulations and prime the separation between embryonic and extraembryonic fates.</p