ERC FUNDED PROJECTS

Neandertals and Denisovans, an Asian group distantly related to Neandertals, are the closest evolutionary relatives of present-day humans. They are thus of direct relevance for understanding the origin of modern humans and how modern humans differ from their closest relatives. We will generate genome-wide data from a large number of Neandertal and Denisovan individuals from across their geographical and temporal range as well as from other extinct hominin groups which we may discover. This will be possible by automating highly sensitive approaches to ancient DNA extraction and DNA libraries construction that we have developed so that they can be applied to many specimens from many sites in order to identify those that contain retrievable DNA. Whenever possible we will sequence whole genomes and in other cases use DNA capture methods to generate high-quality data from representative parts of the genome. This will allow us to study the population history of Neandertals and Denisovans, elucidate how many times and where these extinct hominins contributed genes to present-day people, and the extent to which modern humans and archaic groups contributed genetically to Neandertals and Denisovans. By retrieving DNA from specimens that go back to the Middle Pleistocene we will furthermore shed light on the early history and origins of Neandertals and Denisovans.

2 350 000 €

Start date: 2016-11-01, End date: 2021-10-31

Correlated electrons are at the forefront of condensed matter theory. Interacting quasi-1D electrons have seen vast progress in analytical and numerical theory, and thus in fundamental understanding and quantitative prediction. Yet, in the 1D limit fluctuations preclude important technological use, particularly of superconductors. In contrast, high-Tc superconductors in 2D/3D are not precluded by fluctuations, but lack a fundamental theory, making prediction and engineering of their properties, a major goal in physics, very difficult. This project aims to combine the advantages of both areas by making major progress in the theory of quasi-1D electrons coupled to an electron bath, in part building on recent breakthroughs (with the PIs extensive involvement) in simulating 1D and 2D electrons with parallelized density matrix renormalization group (pDMRG) numerics. Such theory will fundamentally advance the study of open electron systems, and show how to use 1D materials as elements of new superconducting (SC) devices and materials: 1) It will enable a new state of matter, 1D electrons with true SC order. Fluctuations from the electronic liquid, such as graphene, could also enable nanoscale wires to appear SC at high temperatures. 2) A new approach for the deliberate engineering of a high-Tc superconductor. In 1D, how electrons pair by repulsive interactions is understood and can be predicted. Stabilization by reservoir - formed by a parallel array of many such 1D systems - offers a superconductor for which all factors setting Tc are known and can be optimized. 3) Many existing superconductors with repulsive electron pairing, all presently not understood, can be cast as 1D electrons coupled to a bath. Developing chain-DMFT theory based on pDMRG will allow these materials SC properties to be simulated and understood for the first time. 4) The insights gained will be translated to 2D superconductors to study how they could be enhanced by contact with electronic liquids.

1 491 013 €

Start date: 2018-10-01, End date: 2024-03-31

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

Since its discovery, graphene has been indicated as a promising platform for quantum technologies (QT). The number of theoretical proposal dedicated to this vision has grown steadily, exploring a wide range of directions, ranging from spin and valley qubits, to topologically-protected states. The experimental confirmation of these ideas lagged so far significantly behind, mostly because of material quality problems. The quality of graphene-based devices has however improved dramatically in the past five years, thanks to the advent of the so-called van der Waals (vdW) heteostructures - artificial solids formed by mechanically stacking layers of different two dimensional (2D) materials, such as graphene, hexagonal boron nitride and transition metal dichalcogenides. These new advances open now finally the door to put several of those theoretical proposals to test. The goal of this project is to assess experimentally the potential of graphene-based heterostructures for QT applications. Specifically, I will push the development of an advanced technological platform for vdW heterostructures, which will allow to give quantitative answers to the following open questions: i) what are the relaxation and coherence times of spin and valley qubits in isotopically purified bilayer graphene (BLG); ii) what is the efficiency of a Cooper-pair splitter based on BLG; and iii) what are the characteristic energy scales of topologically protected quantum states engineered in graphene-based heterostructures. At the end of this project, I aim at being in the position of saying whether graphene is the horse-worth-betting-on predicted by theory, or whether it still hides surprises in terms of fundamental physics. The technological advancements developed in this project for integrating nanostructured layers into vdW heterostructures will reach even beyond this goal, opening the door to new research directions and possible applications.

1 806 250 €

Start date: 2019-09-01, End date: 2024-08-31