The detailed characterization of proteins is a key step toward the understanding of biological processes on a molecular level. The determination of their three-dimensional structures, which is central to such a characterization, can resolve many mechanistic questions related to function. However, this static picture of biology on a molecular level ignores the dynamic nature of living processes, which is necessary to perform the molecular function. NMR spectroscopy is exquisitely suited to probe the dynamics of biomolecules, because of its capability to deliver atomic-resolution information about the conformational space that a protein samples and the rates at which different conformational states interconvert. This accessibility to both structural and kinetic aspects of protein flexibility has indeed made solution-state NMR spectroscopy an important technique for the understanding of protein function. An important part of biology, however, is actually not occurring in the solution state: exciting systems of outstanding biological relevance such as membrane proteins or amyloid fibrils are very difficult – if at all – amenable to solution-state NMR. Solid-state NMR has seen great progress in the past decade, and the structure and local dynamics of immobilized proteins can now also be studied at atomic resolution. While this promises exciting new insight into the function of these molecules, it remains to establish the methodology that will allow to extract information about dynamics on different time scales in an accurate and reliable manner. The project presented here aims at developing new methods and improving existing methods for the quantification of motional amplitudes and time scales in solid-state proteins. A particular emphasis will be made on solid-state NMR methods that address protein dynamics in the time window of microseconds to seconds. This is a particularly interesting time scale where the function of many proteins occurs. The understanding of intrinsic protein dynamics in this regime can therefore provide important insight into protein function. The methods developed in this project will allow to study a wide range of biophysical processes. They will be applied here to two membrane proteins: the potassium channel KcsA and the mitochondrial ADP/ATP transporter. The foreseen results will shed light onto the molecular mechanisms of trans-membrane transport in these two proteins.

The project VasKho articulates around the two major theories which revolutionized knot theory over the past twenty years, namely the notions of finite-type invariants and categorification. On one hand, the theory of finite-type invariants, initiated by Goussarov and Vassiliev, provides a unified framework for the study of invariants of knots and knotted objects which includes, in particular polynomial invariants. On the other hand, the theory of categorification considerably enhanced polynomial invariants by interpretating them as the graded Euler characteristic of some richer invariants of homological nature. It includes, for instance, the Khovanov and Heegaard-Floer homologies. There are two main parts in this project. The first one proposes to pursue the study of some of the central problems raised in each of these theories (Tasks 1 and 2). They concern knotted objects, such as usual/virtual/welded links and braids, as well as 3-manifolds. The second part aims at the study of the yet widely open problem of the nature of the connections between finite-type invariants and categorification (Task 3). The project involves four freshly hired Maîtres de Conférence who are all specialized in finite-type invariants or categorification, and aims at creating a french network on these subjects and their interactions.

O. Arcizet has been recruited as a Chargé de Recherche at CNRS in the Near Field Microscopies group at Institut Néel (Grenoble) in December 2009 and starts developing his own research activities, for which financial support by the ANR is requested. The goal of the QNAO project consists in extending the thematic of cavity optomechanics at low phonon number down to the nanoscale and observing the first quantum signatures on hybrid systems made of nanomechanical oscillators and single two-level-systems (TLS). From their low mass and higher mechanical susceptibility, nano-resonators are ideal tools for week forces measurements. Sensitivities at the attoNewton have already been reported, which could facilitate the access to the quantum regime of radiation pressure. Such systems could be naturally exploited in solid state physics experiments at the condition to be able to detect and control their Brownian motion. To do so, an ultrasensitive optical near-field sensor of the nano-motion based on ultra high-Q optical microcavities will be developed. The core part of the project aims at studying the coupling of a nano-resonator to a single quantum emitter: a color center in diamond, the Nitrogen Vacancy (NV) defect. These defects have been widely studied over the last decade, a consequence of their ability to generate single photons on demand and the important control gained on their electronic spin properties. Their fundamental ground state is a triplet whose spin state can be polarized and manipulated by pure optical means, and has been exploited as a quantum register demonstrating record lifetimes at room temperature. NV centre then represents a robust quantum emitter already working in a quantum regime, whose coupling to a nanomechanical oscillator close to its motional ground state will provide a fantastic playground for hybrid quantum optomechanics. For example, in analogy with trapped ion physics, this hybrid optomechanical coupling could be exploited to cool down to the nanomechanical oscillator down to its vibrational ground state. The goal of the project consists in observing the first quantum signatures in this new setting and studying the resonant optomechanical coupling to a single emitter. Both resonant optomechanical coupling (impulsion transfer, radiation pressure), and magnetic coupling to its electronic spin will be studied. As recently noticed, the latter could allow reaching the strong coupling regime. Diamond nanomechanical oscillators will be specifically developed and exploited for both their superior mechanical, thermal and superconducting properties and their ability to host distinguishable NV centers that will be created within the structure. The mechanical properties of the nanoresonators produced will be studied by means of the near field displacement sensor, while its optical and electronic spin properties will be investigated on a homebuilt confocal microscope integrating a microwave excitation for observing electronic spin resonances. A cryogenic experiment will be developed after a pre-characterization phase, aiming at observing the first quantum signatures in this new hybrid system. From the exponentially increasing amount of publications and the quality of the groups involved in the fields of both cavity optomechanics at low phonon number and NV physics, it is fair to say that this project is sitting at the verge of two extremely active and competitive fields of modern physic and requires a strong support from the ANR.

Most of our current knowledge of protoplanetary disks originates from studies of the dust component (e.g. spectral energy distributions (SED), scattered light images, emission maps) despite the fact that dust comprises only 1% of the initial mass of the disk.In contrast, the dominant and essential gas component of a protoplanetary disk has proven more difficult to observe thus far. Combining the gas and dust information from protoplanetary disks is particularly important for understanding disk evolution. The Herschel Space Observatory, due to be launched in April of this year, will open an unexplored wavelength window in the far infrared regime, providing access to high-quality observations of the gas in disks. I have been invited to join the "GAS in Protoplanetary Systems" (GASPS) Open Time Key Project that will observe both continuum (dust) and line (gas), namely [CII], [OI] and water, emission for an unbiased sample of 240 young stars, spanning a large range of stellar masses as well as the entire duration of planet formation. This DiskEvol program will tackle the complex problem of combining consistently the constraints on the gas phase of a disk, provided by the Herschel observations, with our existing studies of the dust phase. Interpretation of gas observations is complicated by the large number of physical processes at play: chemistry, excitation and destruction of molecules, freeze-out onto the dust grains, to name a few. But, this is of particular importance as the dissipation of abundant gas remnant from star formation limits the timescale for giant planet formation, controls the dynamics of planetary bodies (of all sizes) during their formation and determines the final architecture of the planetary system. This proposal will rely on 1) the preparation of a database including observations and models for the GASPS project, resultant from ancillary data for GASPS in the millimetre regime and the generation of grids of radiative transfer models (SEDs and line fluxes), respectively. This initial work will allow 2) a detailed analysis of the GASPS program through a statistical comparison of the GASPS observations with the predictions from the grid of models. This global study, of the large sample of disks observed by GASPS, will be 3) extended and completed through finer detailed modelling of a selected sample of representative sources for which we will obtain a complete view of the dust structure and gas chemistry using simultaneous interpretation of continuum observations, resolved emission maps in low-level rotational lines of CO, in addition to follow-up observations with HIFI, a high-spectral resolution instrument on-board Herschel. DiskEvol will provide an unprecedented inventory of gas and dust in protoplanetary disks, transforming our understanding of disk evolution by addressing key questions on the timescales and main mechanisms of dust and gas evolution within disks. In addition, the long-lasting value of DiskEvol results is of exceptional importance in the era of ALMA and JWST.