ERC FUNDED PROJECTS

"The A2C2 project treats two major challenges in climate and atmospheric research: the time dependence of the climate attractor to external forcings (solar, volcanic eruptions and anthropogenic), and the attribution of extreme climate events occurring in the northern extra-tropics. The main difficulties are the limited climate information, the computer cost of model simulations, and mathematical assumptions that are hardly verified and often overlooked in the literature. A2C2 proposes a practical framework to overcome those three difficulties, linking the theory of dynamical systems and statistics. We will generalize the methodology of flow analogues to multiple databases in order to obtain probabilistic descriptions of analogue decompositions. The project is divided into three workpackages (WP). WP1 embeds the analogue method in the theory of dynamical systems in order to provide a metric of an attractor deformation in time. The important methodological step is to detect trends or persisting outliers in the dates and scores of analogues when the system yields time-varying forcings. This is done from idealized models and full size climate models in which the forcings (anthropogenic and natural) are known. A2C2 creates an open source toolkit to compute flow analogues from a wide array of databases (WP2). WP3 treats the two scientific challenges with the analogue method and multiple model ensembles, hence allowing uncertainty estimates under realistic mathematical hypotheses. The flow analogue methodology allows a systematic and quasi real-time analysis of extreme events, which is currently out of the reach of conventional climate modeling approaches. The major breakthrough of A2C2 is to bridge the gap between operational needs (the immediate analysis of climate events) and the understanding long-term climate changes. A2C2 opens new research horizons for the exploitation of ensembles of simulations and reliable estimates of uncertainty."

1 491 457 €

Start date: 2014-03-01, End date: 2019-02-28

The emergence of coherent behaviour is ubiquitous in the natural world and has long captivated biologists and physicists alike. One area of growing interest is the collective motion and synchronization arising within and between simple motile organisms. My goal is to develop and use a novel experimental approach to unravel the origins of spontaneous coherent motion in three model systems of biofluids: (1) the synchronization of the two flagella of green algae Chlamydomonas Rheinhardtii, (2) the metachronal wave in the cilia of protist Paramecium and (3) the collective motion of swimming microorganisms in active suspensions. Understanding the mechanisms leading to collective motion is of tremendous importance because it is crucial to many biological processes such as mechanical signal transduction, embryonic development and biofilm formation. Up till now, most of the work has been theoretical and has led to the dominant view that hydrodynamic interactions are the main driving force for synchronization and collective motion. Recent experiments have challenged this view and highlighted the importance of direct mechanical contact. New experimental studies are now crucially needed. The state-of-the-art of experimental approaches consists of observations of unperturbed cells. The key innovation in our approach is to dynamically interact with microorganisms in real-time, at the relevant time and length scales. I will investigate the origins of coherent motion by reproducing synthetically the mechanical signatures of physiological flows and direct mechanical interactions and track precisely the response of the organism to the perturbations. Our new approach will incorporate optical tweezers to interact with motile cells, and a unique μ-Tomographic PIV setup to track their 3D micron-scale motion. This proposal tackles a timely question in biophysics and will yield new insight into the fundamental principles underlying collective motion in active biological matter.

1 500 000 €

Start date: 2017-04-01, End date: 2022-03-31

My proposal seeks to explain the complex interplay between genetic and environmental causes of individual variation in substance use and the risk for abuse. Substance use is common. Substances like nicotine and cannabis have well-known negative health consequences, while alcohol and caffeine use may be both beneficial and detrimental, depending on quantity and frequency of use. Twin studies (including my own) demonstrated that both heritable and environmental factors play a role. My proposal on substance use (nicotine, alcohol, cannabis and caffeine) is organized around several key objectives: 1. To unravel the complex contribution of genetic and environmental factors to substance use by using extended twin family designs; 2. To identify and confirm genes and gene networks involved in substance use by using DNA-variant data; 3. To explore gene expression patterns with RNA data in substance users versus non-users; 4. To investigate biomarkers in substance users versus non-users using blood or urine; 5. To unravel relation between substance use and health by linking twin-family data to national medical databases. To realize these aims I will use the extensive resources of the Netherlands Twin Register (NTR); including both the longitudinal phenotype database and the biological samples. I have been involved in data collection, coordination of data collection and analyzing NTR data since 1999. With my comprehensive experience in data collection, data analyses and my knowledge in the field of behavior genetics and addiction research I will be able to successfully lead this cutting-edge project. Additional data crucial for the project will be collected by my team. Large samples will be available for this study and state-of-the art methods will be used to analyze the data. All together, my project will offer powerful approaches to unravel the complex interaction between genetic and environmental causes of individual differences in substance use and the risk for abuse.

1 491 964 €

Start date: 2011-12-01, End date: 2017-05-31

The rise of atmospheric O2 ~2,500 million years ago is one of the most profound transitions in Earth's history. Yet, despite its central role in shaping Earth's surface environment, the cause for the rise of O2 remains poorly understood. Tight coupling between the O2 cycle and the biogeochemical cycles of redox-active elements, such as C, Fe and S, implies radical changes in these cycles before, during and after the rise of O2. These changes, too, are incompletely understood, but have left valuable information encoded in the geological record. This information has been qualitatively interpreted, leaving many aspects of the rise of O2, including its causes and constraints on ocean chemistry before and after it, topics of ongoing research and debate. Here, I outline a research program to address this fundamental question in geochemical Earth systems evolution. The inherently interdisciplinary program uniquely integrates laboratory experiments, numerical models, geological observations, and geochemical analyses. Laboratory experiments and geological observations will constrain unknown parameters of the early biogeochemical cycles, and, in combination with field studies, will validate and refine the use of paleoenvironmental proxies. The insight gained will be used to develop detailed models of the coupled biogeochemical cycles, which will themselves be used to quantitatively understand the events surrounding the rise of O2, and to illuminate the dynamics of elemental cycles in the early oceans. This program is expected to yield novel, quantitative insight into these important events in Earth history and to have a major impact on our understanding of early ocean chemistry and the rise of O2. An ERC Starting Grant will enable me to use the excellent experimental and computational facilities at my disposal, to access the outstanding human resource at the Weizmann Institute of Science, and to address one of the major open questions in modern geochemistry.

1 472 690 €

Start date: 2013-09-01, End date: 2018-08-31