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HiPEAC Vision 2025
No full textInternational audienceIn the wake of a series of reports painting a bleak picture of European competitiveness – and hence future prosperity – the HiPEAC Vision 2025 takes a clear-eyed look at the computingsector in the European Union and sets out a series of actionable recommendations applicable to the next 10 years of computing research, covering the computing continuum from edge to cloud to high-performance computing, and tailored to the European context.Taking an analysis of the state of the technology sector as its starting point, the roadmap describes how to implement the “next computing paradigm” (NCP): a computing continuumtailored to the user, where data and code migrate to where it makes sense to process and execute them, and which draws on European strengths such as edge computing, digital twins,factory automation, and management of complex systems to deliver technological solutions to real-world problems.Chapters in this year’s HiPEAC Vision cover the state of the European Union, the NCP, artificial intelligence (AI), new hardware, tools, cyber-physical systems, cybersecurity and sustainability. The document also includes a series of recommendations covering technological themes, methodological approaches, standardization issues, and policy directions
Ultrasensitive interferons quantification reveals different cytokine profile secretion in inflammatory myopathies and can serve as biomarkers of activity in dermatomyositis
No full textInternational audienceObjective The objective of this study was to evaluate the presence of different types of interferon in idiopathic inflammatory myopathies (IIM) and their subgroups using ultrasensitive cytokine detection techniques (SIMOA) and to assess their potential as activity biomarkers. Methods Disease activity was measured at the time of serum collection and assessed by manual muscle testing eight (MMT8 score 0-150), muscle enzymes to calculate the Physician Global Assessment (PGA) (0-10). Patients were classified as active if PGA>5.Serum IFN-α and IFN-γ levels was measured using the single molecule array (SIMOA) technique. Serum IFN-β level was measured by Elisa. Correlation between IFN levels and disease activity were performed. Results We included 242 IIM patients and found a good correlation between type I Interferon (IFN) and dermatomyositis disease activity. IFN-α and IFN-β was highly correlated with disease activity (r=0.76 and r=0,58). To evaluate whether the different types of Interferons could serve as biomarkers of activity, we generated ROC curves. Patients with active DM had a higher median IFN-α level (0.49 pg/ml [0.1-3.7]) compared with non-active patients (0.03 pg/ml [0.01-0.07] p<0.05). The area under the curve was 0.90 IC95 (0.76-0.97) p<0.05. Furthermore, Myositis-specific antibodies appear to be associated with a different secretion profile; patients with anti-MDA 5 antibodies had higher level of IFN-α than most other antibodies (6.58 vs 0.14 p<0.005). NXP2 had higher IFN-β level than patients with Tif1γ antibodies. Conclusion Serum IFN-α level measured by SIMOA is a reliable biomarker of DM activity. Myositis-specific antibodies appear to be associated with a different secretion profile. This data needs to be confirmed in order to select the good therapeutics strategies in DM
Determining the key drivers of the potential secondary battery raw materials supply from the urban mine in the European Union
No full textInternational audienceVehicle stocks in the European Union (EU) can serve as an urban mine for secondary battery raw materials and reduce reliance on international supply chains. A prospective material flow analysis (MFA) model is developed to evaluate the potential of the EU urban mine until 2050. It can support the development of policies concerning focus areas to achieve a circular economy and the definition of target values. The secondary supply is differentiated into production scrap and End-of-Life batteries and the number of recycling loops the materials potentially traverse is analysed. The analysed scenarios show that market developments (e.g., dominant cell chemistries and shared mobility) can influence material demand and the potential secondary supply the most. Meeting the recycled content target values by the EU Batteries Regulation is only realistic with production scrap recycling. The share of material recycled more than once is most likely below 5 % at all times
Interplay of deposition kinetics with metal diffusion in MoO3 -Cu heterojunctions
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Investigating the p- and p-p- dynamics with femtoscopy in pp collisions at TeV
No full textInternational audienceThe interaction between pions and nucleons plays a crucial role in hadron physics. It represents a fundamental building block of the low-energy QCD dynamics and is subject to several resonance excitations. This work studies the p- dynamics using femtoscopic correlations in high-multiplicity pp collisions at TeV measured by ALICE at the LHC. As the final-state interaction between protons and pions is well constrained by scattering experiments and the study of pionic hydrogen, the results give access to information on the particle-emitting source in pp collisions using the femtoscopy methods. The scaling of the source size of primordial protons and pions against their pair transverse mass is extracted. The results are compared with the source sizes studied with p-p, p-K, and - pairs by ALICE in the same collision system and are found to be in agreement for the different particle pairs. This reinforces recent findings by ALICE of a common emission source for all hadron-pairs in pp collisions at LHC energies. Furthermore, the p-p- systems are studied using three-particle femtoscopy in pp collisions at TeV. The presence of three-body effects is analyzed utilizing the cumulant expansion method. In this formalism, the known two-body interactions are subtracted in order to isolate the three-body effects. For both, p-p- and p-p-, a non-zero cumulant is found, indicating effects beyond pairwise interactions. These results give information on the coupling of the pion to multiple nucleons
Forecasting the performance of the Minimally Informed foreground cleaning method for CMB polarization observations
No full textInternational audienceAstrophysical foreground substraction is crucial to retrieve the cosmic microwave background (CMB) polarization out of the observed data. Recent efforts have been carried out towards the development of a minimally informed component separation method to handle a priori unknown foreground spectral energy distributions (SEDs), while being able to estimate both cosmological, foreground, and potentially instrumental parameters, jointly. In this paper, we develop a semi-analytical performance forecasting framework for the minimally informed method and we validate it by comparing its results against direct sampling of the harmonic-based likelihood and the pixel domain implementation MICMAC. We then use the forecasting tool to demonstrate the robustness of the bias correction procedure introduced in the minimally informed approach. We find that a data-driven approach based on the currently available observational data is enough to efficiently regularize the bias of the method
Evaluating present-day and future impacts of agricultural ammonia emissions on atmospheric chemistry and climate
No full textInternational audienceAgricultural practices are a major source of ammonia (NH 3 ) in the atmosphere, which has implications for air quality, climate, and ecosystems. Due to the rising demand for food and feed production, ammonia emissions are expected to increase significantly by 2100 and would therefore impact atmospheric composition such as nitrate (NO - 3 ) or sulfate (SO 2- 4 ) particles and affect biodiversity from enhanced deposition. Chemistryclimate models which integrate the key atmospheric physicochemical processes with the ammonia cycle represent a useful tool to investigate present-day and also future reduced nitrogen pathways and their impact on the global scale. Ammonia sources are, however, challenging to quantify because of their dependencies on environmental variables and agricultural practices and represent a crucial input for chemistry-climate models. In this study, we use the chemistry-climate model LMDZ-INCA (Laboratoire de Météorologie Dynamique-INteraction with Chemistry and Aerosols) with agricultural and natural soil ammonia emissions from a global land surface model ORCHIDEE (ORganising Carbon and Hydrology In Dynamic Ecosystems), together with the integrated module CAMEO (Calculation of AMmonia Emissions in ORCHIDEE), for the present-day and 2090-2100 period under two divergent Shared Socioeconomic Pathways (SSP5-8.5 and SSP4-3.4). Future agricultural emissions under the most increased level (SSP4-3.4) have been further exploited to evaluate the impact of enhanced ammonia emissions combined with future contrasting aerosol precursor emissions (SSP1-2.6 -low emissions; SSP3-7.0 -regionally contrasted emissions). We demonstrate that the CAMEO emission set enhances the spatial and temporal variability in the atmospheric ammonia in regions such as Africa, Latin America, and the US in comparison to the static reference inventory (Community Emissions Data System; CEDS) when assessed against satellite and surface network observations. The CAMEO simulation indicates higher ammonia emissions in Africa relative to other studies, which is corroborated by increased current levels of reduced nitrogen deposition (NH x ), a finding that aligns with observations in west Africa. Future CAMEO emissions lead to an overall increase in the global NH 3 burden ranging from 59 % to 235 %, while the NO - 3 burden increases by 57 %-114 %, depending on the scenario, even when global NO x emissions decrease. When considering the most divergent scenarios (SSP5-8.5 and SSP4-3.4) for agricultural ammonia emissions, the direct radiative forcing resulting from secondary inorganic aerosol changes ranges from -114 to -160 mW m -2 . By combining a high level of NH 3 emissions with decreased or contrasted future sulfate and nitrate emissions, the nitrate radiative effect can either overcompensate (net total sulfate and nitrate effect of -200 mW m -2 ) or be offset by the sulfate effect (net total sulfate and nitrate effect of +180 mW m -2 ). We also show that future oxidation of NH 3 could Published by Copernicus Publications on behalf of the European Geosciences Union. 2018M. Beaudor et al.: Evaluating present-day and future impacts of agricultural ammonia emissions lead to an increase in N 2 O atmospheric sources from 0.43 to 2.10 Tg N 2 O yr -1 compared to the present-day levels, representing 18 % of the future N 2 O anthropogenic emissions. Our results suggest that accounting for nitrate aerosol precursor emission levels but also for the ammonia oxidation pathway in future studies is particularly important to understand how ammonia will affect climate, air quality, and nitrogen deposition.</div
Corrosion du fer dans l'hexafluorure d'uranium à 80°C. Part II : Mécanisme de corrosion
No full textInternational audienceThanks to species identification and growth interface localization experiments, a mechanism of iron corrosion in liquid UF6 at 80 °C was suggested. After an UF6 dissociation step, resulting fluorine (HF, F or F•) was adsorbed at the FeF2 external interface and diffused into the iron fluoride layer via fluorine vacancy. FeF grew thus at the FeF/Fe interface. Two FeF growth kinetics were observed depending on the presence or absence of NOxF impurities. Both corrosion rates were controlled by the cathodic reaction and presence of NOF catalysed it
Atlantic overturning inferred from air-sea heat fluxes indicates no decline since the 1960s
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Enhancing the analysis of correlations in random bit sequences
No full textInternational audienceSince the security of cryptographic schemes relies heavily on RNGs, we need efficient methods to evaluate the statistical properties of numbers they produce. To that end, several statistical tests have been designed and gathered into batteries such as those found in the SP 800-90 and AIS 31 standards. Although these test batteries are aimed at analyzing several statistical anomalies, some of them may overlap in the anomalies they target, making them somewhat inefficient. In this paper, we will show how two tests, namely the Autocorrelation test and the Monobit test, overlap with one another. We will then propose a method to develop a new autocorrelation test which does not overlap with the Monobit test, before proving that our new test outperforms the standard test in all conceivable cases. Finally, we will propose and compare two methods for further analyzing correlations in bit sequences produced by random number generator