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Structural and evolutionary features of red algal UV sex chromosomes
No full textInternational audienceAbstract Background Sex chromosomes in red algae have remained relatively understudied, despite their fundamental role in understanding the evolution of sex determination across eukaryotes. In this study, we investigate the structure, gene composition, and evolutionary history of the U and V sex chromosomes in four Gracilaria species, which diverged approximately 100 million years ago. Results Our findings reveal that UV sex chromosomes, previously identified in green and brown algae as well as bryophytes, have also evolved in red algae, contributing to the diversity of sex determination systems across eukaryotes. The shared orthology of conserved sex-determining region genes between Gracilaria and distantly related red algae suggests that this system may have originated approximately 390 million years ago, making it one of the oldest known sex chromosome systems. The sex-determining region in Gracilaria is relatively small but contains conserved gametologs and V-specific genes involved in transcriptional regulation and signaling, suggesting their essential role in sexual differentiation. Unlike the conserved V-specific genes, U-specific genes appear absent, pointing to a dominant role of the V chromosome in sex determination. Despite their ancient origin, the sex chromosomes show low levels of degeneration, likely due to haploid purifying selection during the gametophytic phase of the life cycle. Conclusions This study provides the first large-scale comparative genomic and transcriptomic analysis of the U and V sex chromosomes across multiple red algal species, preparing the ground for future studies on reproductive life cycles and speciation in this understudied group of eukaryotes
Exploring Marine Biomineralization on the Al–Mg Alloy as a Natural Process for In Situ LDH Growth to Improve Corrosion Resistance
No full textInternational audienceThis study provides a detailed characterization of the AA5083 aluminum alloy, surface, and interface over 6 months of immersion in seawater, employing techniques such as SEM/EDX, GIXRD, μ-Raman and XPS. The purpose was to evaluate the evolution of the biomineralization process that occurs on the Al–Mg alloy. By investigating the specific conditions that favor the in situ growth of layered double hydroxide (LDH) during seawater immersion as a result of biomineralization, this research provides insights into marine biomineralization, highlighting its potential as an innovative and sustainable strategy for corrosion protection
"Un roman d’aventure réel": reporting on the Irish war of independence for a French audience
No full textInternational audienceDuring the revolutionary period, Ireland was on the frontpages of newspapers everywhere in the world. If the 1916 Easter Rising seems to have been misunderstood by the French journalists, the war of independence was described by Joseph Kessel, who was sent to cover the conflict, as the “romantic” rebellion of a small country against one of the most powerful empires in the world. The reporters travelled around Ireland and met many important figures including British officers and Sinn Féin leaders. Added to the textual reporting, in left and right-leaning newspapers alike, was added visual commentary with editorial cartoons and photographs. Articles were to be found on an almost daily basis, revealing how intensive – and almost serialized – the press coverage proved to be. The journalists’ mission was to make the readers discover a country that they knew nothing about in a context that resonated with their personal experience of the First World War. They used different narrative techniques to provoke an emotional reaction in readers whose memories of destruction and suffering were still fresh. The journalists sympathized with the Irish, and many articles reveal their indignation at the brutal British repression. The articles reveal the grey zone between fiction and non-fiction and show the strings they pulled to captivate the French audience, and put pressure on the British government at a time when negative news coverage could already prove detrimental
Optimization of the insulation domain for heat transfer in building walls
No full textInternational audienceThe objective of this paper is to minimize the energy consumption of a building wall by finding the optimal locations of the insulation elementary blocks. The direct problem considers a 2D steady state heat transfer equation. A density (in the mathematical sense) function is introduced to represent the thermal properties of the wall, i.e. insulation blocks and load bearing materials. On the outside boundary surface, the convection and incident short-wave radiation flux vary with space. The objective function is defined as the total heat flux on the inside part of the wall. It is optimized respecting the constraint of proportion insulation/load bearing material given by standard wall configurations. The optimal locations of the insulation material blocks are retrieved using an exchange algorithm. It ensures to find a local minimum solution with a reduced computational effort. Finally, a case study located in Paris investigates the thermal design optimization. Results show the efficiency of the numerical strategy. On the top of that, the aim of the study is reached by obtaining an improved energy efficient wall with optimized insulation locations.</div
D5.3: Exploitation plan
No full textThe present deliverable provides an overview of the exploitation activities related to the research outcomes of the ANR Mitik project. This report outlines how the project consortium has engaged in the application of its research findings to maximize their impact. The aim is to ensure that the knowledge generated throughout the project contributes to both academic advancements and broader societal benefits. Through these exploitation activities, the project seeks to foster innovation, enhance collaboration, and create pathways for future research and development
Development of a GHG-based control strategy for a fleet of hybrid heat pumps to decarbonize space heating and domestic hot water
No full textInternational audienceIn Europe, the building sector accounts for approximately 35 % of the energy-related emissions. Hybrid systems coordinating heat pumps and gas boilers can avoid greenhouse gas (GHG) emissions from carbonized electricity production by providing demand-side flexibility without any service interruption. This work aimed to develop a control strategy for a fleet of hybrid heat pumps to reduce GHG emissions. The electricity and gas consumption of a fleet of 3000 hybrid heat pumps, heating 100,000 dwellings spread throughout France, was evaluated. A Modelica model of a district archetype was simulated in seven cities representative of the French climatic zones to obtain the national heating demand. The marginal emission factor of the electricity consumption was assessed using a French power system model coupled with marginal emission factors for interconnected power systems, which were assessed through linear regressions. Two types of control strategies (prioritizing the heat pump and fuel switch) are evaluated considering 4 different sizing for the heat pump (120 %, 50 %, 35 %, and 20 %). Between July 2018 and June 2019, a strategy prioritizing the heat pumps would have avoided between 8000 and 26,000 tCO2eq for the power system. A strategy switching between the heat pump and the boiler based on the marginal emission factor of the electricity consumption would have avoided around 38,000 tCO2eq, with a limited influence of the sizing of the heat pump
