22 research outputs found

    Regional uptake of direct reduction iron production using hydrogen under climate policy

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    The need to reduce CO2 emissions to zero by 2050 has meant an increasing focus on high emitting industrial sectors such as steel. However, significant uncertainties remain as to the rate of technology diffusion across steel production pathways in different regions, and how this might impact on climate ambition. Informed by empirical analysis of historical transitions, this paper presents modelling on the regional deployment of Direction Reduction Iron using hydrogen (DRI-H2). We find that DRI-H2 can play a leading role in the decarbonisation of the sector, leading to near-zero emissions by 2070. Regional spillovers from early to late adopting regions can speed up the rate of deployment of DRI-H2, leading to lower cumulative emissions and system costs. Without such effects, cumulative emissions are 13% higher than if spillovers are assumed and approximately 15% and 20% higher in China and India respectively. Given the estimates of DRI-H2 cost-effectiveness relative to other primary production technologies, we also find that costs increase in the absence of regional spillovers. However, other factors can also have impacts on deployment, emission reductions, and costs, including the composition of the early adopter group, material efficiency improvements and scrap recycling rates. For the sector to achieve decarbonisation, key regions will need to continue to invest in low carbon steel projects, recognising their broader global benefit, and look to develop and strengthen policy coordination on technologies such as DRI-H2

    Etude de l'impact des avions sur la composition chimique de l'atmosphĂšre

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    TOULOUSE3-BU Sciences (315552104) / SudocSudocFranceF

    Response in ozone and methane to small emission changes and dependence on cruise altitude

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    Within the scope of the LEEA (Low Emissions Effect Aircraft) project the effects of small changes in aircraft NOX emissions on CH4-NOX-O3 chemistry were systematically investigated with the ultimate objective to develop a parametric relationship between the amount / altitude / location of emissions and their effect on the climate system. A large number of sensitivity experiments were carried out with the global 3D CTM p-TOMCAT. Aircraft emission data was used from the European AERO2k Global Aviation Emissions Inventory for 2002. In the experiments the standard emission profile was altered such that, within discrete cruise altitude bands in the altitude range 5–15 km, emissions were globally increased by 5–20%. Investigation of ozone precursor concentrations, ozone production efficiency and methane lifetime has shown both highly linear and additive behaviour in the atmospheric response to the emission perturbations that were applied. This suggests that in future a linear parameterisation can be used to predict the effects of small emission changes on the chemistry in the UTLS region. The LEEA project was funded by Airbus UK and the Department for Trade and Industry

    Climate impact of supersonic air traffic: an approach to optimize a potential future supersonic fleet – results from the EU-project SCENIC

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    The demand for intercontinental transportation is increasing and people are requesting short travel times, which supersonic air transportation would enable. However, besides noise and sonic boom issues, which we are not referring to in this investigation, 5 emissions from supersonic aircraft are known to alter the atmospheric composition, in particular the ozone layer, and hence affect climate significantly more than subsonic aircraft. Here, we suggest a metric to quantitatively assess different options for supersonic transport with regard to the potential destruction of the ozone layer and climate impacts. Options for fleet size, engine technology (nitrogen oxide emission level), cruis10 ing speed, range, and cruising altitude, are analyzed, based on SCENIC emissions scenarios for 2050, which underlay the requirements to be as realistic as possible in terms of e.g. economic markets and profitable market penetration. This methodology is based on a number of atmosphere-chemistry and climate models to reduce mode dependencies. The model results differ significantly in terms of the response to a re15 placement of subsonic aircraft by supersonic aircraft. However, model differences are smaller when comparing the different options for a supersonic fleet. The base scenario, where supersonic aircraft get in service in 2015, a first fleet fully operational in 2025 and a second in 2050, lead in our simulations to a near surface temperature increase in 2050 of around 7mK and with constant emissions afterwards to around 21mK in 2100. The related total radiative forcing amounts to 22 mW/m2 20 in 2050, with an uncertainty between 9 and 29 mW/m2 . A reduced supersonic cruise altitude or speed (from March 2 to Mach 1.6) reduces both, climate impact and ozone destruction, by around 40%. An increase in the range of the supersonic aircraft leads to more emissions at lower latitudes since more routes to SE Asia are taken into account, which increases ozone 25 depletion, but reduces climate impact compared to the base case

    Plasmodium berghei leucine-rich repeat protein 1 downregulates protein phosphatase 1 activity and is required for efficient oocyst development.

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    Protein phosphatase 1 (PP1) is a key enzyme for Plasmodium development. However, the detailed mechanisms underlying its regulation remain to be deciphered. Here, we report the functional characterization of the Plasmodium berghei leucine-rich repeat protein 1 (PbLRR1), an orthologue of SDS22, one of the most ancient and conserved PP1 interactors. Our study shows that PbLRR1 is expressed during intra-erythrocytic development of the parasite, and up to the zygote stage in mosquitoes. PbLRR1 can be found in complex with PbPP1 in both asexual and sexual stages and inhibits its phosphatase activity. Genetic analysis demonstrates that PbLRR1 depletion adversely affects the development of oocysts. PbLRR1 interactome analysis associated with phospho-proteomics studies identifies several novel putative PbLRR1/PbPP1 partners. Some of these partners have previously been characterized as essential for the parasite sexual development. Interestingly, and for the first time, Inhibitor 3 (I3), a well-known and direct interactant of Plasmodium PP1, was found to be drastically hypophosphorylated in PbLRR1-depleted parasites. These data, along with the detection of I3 with PP1 in the LRR1 interactome, strongly suggest that the phosphorylation status of PbI3 is under the control of the PP1-LRR1 complex and could contribute (in)directly to oocyst development. This study provides new insights into previously unrecognized PbPP1 fine regulation of Plasmodium oocyst development through its interaction with PbLRR1

    Napoléon et les Amériques

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    Ce volume prĂ©sente des travaux rĂ©cents sur une dimension peu Ă©tudiĂ©e de l’histoire napolĂ©onienne et atlantique, rassemblant des spĂ©cialistes de l’histoire nord-amĂ©ricaine, latino-amĂ©ricaine et europĂ©enne. Sans prĂ©tendre fournir un traitement exhaustif du vĂ©ritable choc qu’a produit NapolĂ©on dans le monde atlantique - de la vente de la Louisiane aux Etats-Unis et de la rĂ©volution haĂŻtienne jusqu’aux mouvements d’indĂ©pendance ibĂ©ro-amĂ©ricains - dans l’ensemble les diffĂ©rents chapitres permettent de suivre les consĂ©quences directes et indirectes du retrait français de l’AmĂ©rique aprĂšs 1804-1805, et suggĂšrent comment les guerres mondiales et les programmes rĂ©formateurs de l’ùre napolĂ©onienne ont contribuĂ© aux sociĂ©tĂ©s post-impĂ©riales qui ont Ă©mergĂ© dans l’espace atlantique. En tant que tel, ce livre offre aux spĂ©cialistes des Ă©tudes napolĂ©oniennes une nouvelle approche des thĂšmes classiques de la modernisation dans les domaines militaire, religieux, juridique et administratif et s’étend jusqu’aux politiques artistiques et aux influences culturelles dans les AmĂ©riques
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