ERC FUNDED PROJECTS

The overall goal of 14Constraint is to enhance the availability and use of radiocarbon data as constraints for process-based understanding of the age distribution of carbon in and respired by soils and ecosystems. Carbon enters ecosystems by a single process, photosynthesis. It returns by a range of processes that depend on plant allocation and turnover, the efficiency and rate of litter decomposition and the mechanisms stabilizing C in soils. Thus the age distribution of respired CO2 and the age of C residing in plants, litter and soils are diagnostic properties of ecosystems that provide key constraints for testing carbon cycle models. Radiocarbon, especially the transit of ‘bomb’ 14C created in the 1960s, is a powerful tool for tracing C exchange on decadal to centennial timescales. 14Constraint will assemble a global database of existing radiocarbon data (WP1) and demonstrate how they can constrain and test ecosystem carbon cycle models. WP2 will fill data gaps and add new data from sites in key biomes that have ancillary data sufficient to construct belowground C and 14C budgets. These detailed investigations will focus on the role of time lags caused in necromass and fine roots, as well as the dynamics of deep soil C. Spatial extrapolation beyond the WP2 sites will require sampling along global gradients designed to explore the relative roles of mineralogy, vegetation and climate on the age of C in and respired from soil (WP3). Products of this 14Constraint will include the first publicly available global synthesis of terrestrial 14C data, and will add over 5000 new measurements. This project is urgently needed before atmospheric 14C levels decline to below 1950 levels as expected in the next decade.

2 283 747 €

Start date: 2016-12-01, End date: 2021-11-30

The scientific goal of the proposal is to answer central questions related to diffeomorphism groups of manifolds of dimension 2 and 3, and to their deformation invariant analogs, the mapping class groups. While the classification of surfaces has been known for more than a century, their automorphism groups have yet to be fully understood. Even less is known about diffeomorphisms of 3-manifolds despite much interest, and the objects here have only been classified recently, by the breakthrough work of Perelman on the Poincar\'e and geometrization conjectures. In dimension 2, I will focus on the relationship between mapping class groups and topological conformal field theories, with applications to Hochschild homology. In dimension 3, I propose to compute the stable homology of classifying spaces of diffeomorphism groups and mapping class groups, as well as study the homotopy type of the space of diffeomorphisms. I propose moreover to establish homological stability theorems in the wider context of automorphism groups and more general families of groups. The project combines breakthrough methods from homotopy theory with methods from differential and geometric topology. The research team will consist of 3 PhD students, and 4 postdocs, which I will lead.

724 992 €

Start date: 2009-11-01, End date: 2014-10-31

For many years, the ubiquitin-26S proteasome degradation pathway was considered the primary route for proteasomal degradation. However, it is now becoming clear that proteins can also be targeted for degradation by a ubiquitin-independent mechanism mediated by the core 20S proteasome itself. Although initially believed to be limited to rare exceptions, degradation by the 20S proteasome is now understood to have a wide range of substrates, many of which are key regulatory proteins. Despite its importance, little is known about the mechanisms that control 20S proteasomal degradation, unlike the extensive knowledge acquired over the years concerning degradation by the 26S proteasome. Our overall aim is to reveal the multiple regulatory levels that coordinate the 20S proteasome degradation route. To achieve this goal we will carry out a comprehensive research program characterizing three distinct levels of 20S proteasome regulation: Intra-molecular regulation- Revealing the intrinsic molecular switch that activates the latent 20S proteasome. Inter-molecular regulation- Identifying novel proteins that bind the 20S proteasome to regulate its activity and characterizing their mechanism of function. Cellular regulatory networks- Unraveling the cellular cues and multiple pathways that influence 20S proteasome activity using a novel systematic and unbiased screening approach. Our experimental strategy involves the combination of biochemical approaches with native mass spectrometry, cross-linking and fluorescence measurements, complemented by cell biology analyses and high-throughput screening. Such a multidisciplinary approach, integrating in vitro and in vivo findings, will likely provide the much needed knowledge on the 20S proteasome degradation route. When completed, we anticipate that this work will be part of a new paradigm – no longer perceiving the 20S proteasome mediated degradation as a simple and passive event but rather a tightly regulated and coordinated process.

1 500 000 €

Start date: 2015-04-01, End date: 2020-03-31

2D-PnictoChem aims at exploring the Chemistry of a novel class of graphene-like 2D layered elemental materials of group 15, the pnictogens: P, As, Sb, and Bi. In the last few years, these materials have taken the field of Materials Science by storm since they can outperform and/or complement graphene properties. Their strongly layer-dependent unique properties range from semiconducting to metallic, including high carrier mobilities, tunable bandgaps, strong spin-orbit coupling or transparency. However, the Chemistry of pnictogens is still in its infancy, remaining largely unexplored. This is the niche that 2D-PnictoChem aims to fill. By mastering the interface chemistry, we will develop the assembly of 2Dpnictogens in complex hybrid heterostructures for the first time. Success will rely on a cross-disciplinary approach combining both Inorganic- and Organic Chemistry with Solid-state Physics, including: 1) Synthetizing and exfoliating high quality ultra-thin layer pnictogens, providing reliable access down to the monolayer limit. 2) Achieving their chemical functionalization via both non-covalent and covalent approaches in order to tailor at will their properties, decipher reactivity patterns and enable controlled doping avenues. 3) Developing hybrid architectures through a precise chemical control of the interface, in order to promote unprecedented access to novel heterostructures. 4) Exploring novel applications concepts achieving outstanding performances. These are all priorities in the European Union agenda aimed at securing an affordable, clean energy future by developing more efficient hybrid systems for batteries, electronic devices or applications in catalysis. The opportunity is unique to reduce Europe’s dependence on external technology and the PI’s background is ideally suited to tackle these objectives, counting as well on a multidisciplinary team of international collaborators.

1 499 419 €

Start date: 2018-11-01, End date: 2023-10-31