ERC FUNDED PROJECTS

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

"Electrical motors consume about 40 % of the electrical energy produced in the European Union. About 90 % of this energy is converted to mechanical work. However, 0.5-2.5 % of it goes to so called additional load losses whose exact origins are unknown. Our ambitious aim is to reveal the origins of these losses, build up numerical tools for modeling them and optimize electrical motors to minimize the losses. As the hypothesis of the research, we assume that the additional losses mainly result from the deterioration of the core materials during the manufacturing process of the machine. By calorimetric measurements, we have found that the core losses of electrical machines may be twice as large as comprehensive loss models predict. The electrical steel sheets are punched, welded together and shrink fit to the frame. This causes residual strains in the core sheets deteriorating their magnetic characteristics. The cutting burrs make galvanic contacts between the sheets and form paths for inter-lamination currents. Another potential source of additional losses are the circulating currents between the parallel strands of random-wound armature windings. The stochastic nature of these potential sources of additional losses puts more challenge on the research. We shall develop a physical loss model that couples the mechanical strains and electromagnetic losses in electrical steel sheets and apply the new model for comprehensive loss analysis of electrical machines. The stochastic variables related to the core losses and circulating-current losses will be discretized together with the temporal and spatial discretization of the electromechanical field variables. The numerical stochastic loss model will be used to search for such machine constructions that are insensitive to the manufacturing defects. We shall validate the new numerical loss models by electromechanical and calorimetric measurements."

2 489 949 €

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

Atmospheric Gas-to-Particle conversion (ATM-GTP) is a 5-year project focusing on one of the most critical atmospheric processes relevant to global climate and air quality: the first steps of atmospheric aerosol particle formation and growth. The project will concentrate on the currently lacking environmentally-specific knowledge about the interacting, non-linear, physical and chemical atmospheric processes associated with nano-scale gas-to-particle conversion (GTP). The main scientific objective of ATM-GTP is to create a deep understanding on atmospheric GTP taking place at the sub-5 nm size range, particularly in heavily-polluted Chinese mega cities like Beijing and in pristine environments like Siberia and Nordic high-latitude regions. We also aim to find out how nano-GTM is associated with air quality-climate interactions and feedbacks. We are interested in quantifying the effect of nano-GTP on the COBACC (Continental Biosphere-Aerosol-Cloud-Climate) feedback loop that is important in Arctic and boreal regions. Our approach enables to point out the effective reduction mechanisms of the secondary air pollution by a factor of 5-10 and to make reliable estimates of the global and regional aerosol loads, including anthropogenic and biogenic contributions to these loads. We can estimate the future role of Northern Hemispheric biosphere in reducing the global radiative forcing via the quantified feedbacks. The project is carried out by the world-leading scientist in atmospheric aerosol science, being also one of the founders of terrestrial ecosystem meteorology, together with his research team. The project uses novel infrastructures including SMEAR (Stations Measuring Ecosystem Atmospheric Relations) stations, related modelling platforms and regional data from Russia and China. The work will be carried out in synergy with several national, Nordic and EU research-innovation projects: Finnish Center of Excellence-ATM, Nordic CoE-CRAICC and EU-FP7-BACCHUS.

2 500 000 €

Start date: 2017-06-01, End date: 2022-05-31

Biomechanical interactions between cells and their environment are essential in almost any biological process, from embryonic development to organ function to diseases. Hence, biomechanical interactions are crucial for health and disease. Examples are hydrodynamic interactions through fluid flow, and forces acting directly on cells. Existing methods to analyze and understand these interactions are limited however, since they do not offer the required combination of precisely controlled flow and accurate applying and sensing of forces. Also, they often lack a physiological environment. A breakthrough in biomechanical analysis is therefore highly needed. We will realize a novel microfluidic platform for biomechanical analysis with unprecedented possibilities of controlling fluid flow and applying and sensing time-dependent forces at subcellular scales in controlled environments. The platform will be uniquely based on bio-inspired magnetic artificial cilia, rather than on conventional microfluidic valves and pumps. Cilia are microscopic hairs ubiquitously present in nature, acting both as actuators and sensors, essential for swimming of microorganisms, transport of dirt out of our airways, and sensing of sound, i.e. they exactly fulfill functions needed in biomechanical analysis. We will develop novel materials and fabrication methods to realize microscopic polymeric artificial cilia, and integrate these in microfluidic devices. Magnetic actuation and optical readout systems complete the platform. We will apply the novel platform to address three fundamental and unresolved biomechanical questions: 1. How do hydrodynamic interactions with actuated cilia steer cellular and particle transport? 2. How do local and dynamic mechanical forces on cells fundamentally influence their motility and differentiation? 3. How do hydrodynamic interactions between cilia steer embryonic development? This unique platform will enable to address many other future biomechanical questions.

3 083 625 €

Start date: 2019-10-01, End date: 2024-09-30