Algorithmic Hexahedral Mesh Generation
ERC Starting Grant
Principal investigator: Prof. David Bommes, Institute of Computer Science
Digital geometry representations are nowadays a fundamental ingredient of many applications, as for instance CAD/CAM, fabrication, shape optimization, bio-medical engineering and numerical simulation. Among volumetric discretizations the “holy grail” are hexahedral meshes, i.e. a decomposition of the domain into conforming cube-like elements. For simulations they offer accuracy and efficiency that cannot be obtained with alternatives like tetrahedral meshes, specifically when dealing with higher-order PDEs. So far, automatic hexahedral meshing of general volumetric domains is a long-standing, notoriously difficult and open problem.
The main goal of the AlgoHex team is to develop algorithms for automatic hexahedral meshing of general volumetric domains that are (i) robust, (ii) scalable and (iii) offer precise control on regularity, approximation error and element sizing/anisotropy. The scientific approach is designed to replicate the success story of recent integer-grid map based algorithms for 2D quadrilateral meshing. The underlying methodology offers the essential global view on the problem that was lacking in previous attempts, mostly failing due to local considerations inducing global inconsistencies. Preliminary results of integer-grid map hexahedral meshing are encouraging and a breakthrough is in reach.
Unique Method for a Neutron Electric Dipole Moment Search using a Pulsed Beam
ERC Starting Grant
Principal investigator: Prof. Florian Piegsa, Albert Einstein Center for Fundamental Physics
The BEAM-EDM project encompasses the research and application of novel precision methods in the field of low energy particle physics. The goal of the program is to lead an independent and highly competitive experiment to search for a CP-symmetry violating neutron electric dipole moment (EDM), as well as for new exotic interactions, employing highly sensitive neutron and proton spin resonance techniques.
The measurement of the neutron EDM is considered to be one of the most important fundamental physics experiments at low energy. It represents a promising route for finding new physics beyond the standard model (SM) and describes an important mechanism to understand the observed large matter/antimatter asymmetry in our universe. The project will follow a novel concept, which plans to employ a pulsed neutron beam at high intensity, instead of the established use of storable ultracold neutrons. This complementary method provides the possibility to distinguish between the signal due to a neutron EDM and previously limiting systematic effects, and should lead to an improved result compared to the present best neutron EDM beam experiment. The findings of these investigations will form the cornerstone for the success of a full-scale experiment intended for the European Spallation Source in Sweden.
A second scientific campaign focusing on the search for exotic short-range interactions and associated light bosons will be addressed by employing nuclear spin precession techniques. This is a burgeoning field of research motivated by various extensions to the SM. The goal of this project, using neutrons and protons, is to search for additional interactions between ordinary particles mediated by new bosons and for so-called dark-matter axions.
Both topics describe ambitious and unique efforts. They use related techniques, address important questions in fundamental physics, and have the potential of substantial scientific impact.
ERC Advanced Grant
Principal invesitgator: Prof. Hubertus Fischer, Climate and Environmental Physics
Arguably, the most ambitious objective of the international ice core community for the future is the goal to drill an ice core that continuously covers the last 1.5 Myr. Among others, this will allow to study the greenhouse gas influence on the enigmatic shift from glacial/interglacial cycles with a periodicity of 40,000 years prior to 900,000 years before present to the 100,000 year cycles encountered in the late Quaternary. The European ice core community, of which the ice core group at the division for Climate and Environmental Physics at the University of Bern is an integral part, will drill such an ice core in the coming years within the EU project "Beyond EPICA - Oldest Ice Core", funded through the EU and national contributions for example by the SNF.
However, due to glacier flow, the climate record older than 700 kyr of such an Oldest Ice core will be confined to the bottom-most 200 m of the ice sheet. Accordingly, this record will be highly compressed and the amount of ice available for ice core analyses will be strongly limited. Thus, the goal of obtaining all the climate records from this limited amount of ice can only be achieved using novel analysis techniques, which excel in sensitivity, precision, and sample consumption over previous approaches. In the ERC advanced grant deepSLice of Prof. Hubertus Fischer exactly such a new analytical approach is currently developed, consisting of a new quantitative semi-continuous sublimation extraction for ice core gas samples connected to a dual-wavelength Quantum Cascade Laser Spectrometer to measure CO2, CH4, N2O and CO2 isotopes on only 15 g of ice. The laser spectrometer is developed in close collaboration with the grouf of Dr. Lukas Emmengger at the Swiss Federal Laboratories for Materials Science and Technology, Empa.
The Climates and Habitability of Small Exoplanets Around Red Stars
ERC Consolidator Grant
Principal investigator: Prof. Kevin Heng, Center for Space and Habitability
The detection of life beyond our Solar System is possible only via the remote sensing of the atmospheres of exoplanets. The recent discovery that small exoplanets are common around cool, red stars offers an exciting opportunity to study the atmospheres of Earth-like worlds. Motivated by this revelation, the EXOKLEIN project proposes to construct a holistic climate framework to understand astronomical observations in the context of the atmosphere, geochemistry and biosignatures of the exoplanet. The proposed research is divided into three major themes. Research Theme 1 aims to construct a virtual laboratory of an atmosphere that considers atmospheric dynamics, chemistry and radiation, as well as how they interact. Research Theme 2 aims to generalize the carbonate-silicate cycle (also known as the long-term carbon cycle) by considering variations in rock composition, water acidity and atmospheric conditions. The carbonate-silicate cycle is important because it regulates the long-term presence of carbon dioxide (a vital greenhouse gas) in atmospheres. Research Theme 3 aims to investigate the long-term stability of biosignature gases in the context of the climate. Overall, the EXOKLEIN project will significantly advance our understanding of whether the environments of rocky exoplanets around red stars are stable and conducive for life, and whether the tell-tale signatures of life may be detected by astronomers.
Exploring the dynamics and causes of prehistoric land use change in the cradle of European farming
ERC Synergy Grant
Principal investigator: Prof. Willy Tinner, Institute for Plant Sciences & Oeschger Center for Climate Change Research/Prof. Albert Hafner, Institute for Archaeological Sciences
More than 8000 years ago, technological and social breakthroughs allowed the introduction of farming from western Asia to Greece and thus for the first time to Europe. In the ERC synergy-project EXPLO (Exploring the dynamics and causes of prehistoric land use change in the cradle of European farming) we work with archaeologists from University of Bern (head Albert Hafner), University of Oxford (head Amy Bogaard) and University of Thessaloniki (head Kostas Kotsakis). While the archaologists are working with on-site records (i.e. in former settlements), we as biologists and climate scientists are analyzing off-site natural archives (e.g. lakes) to study the linkages between vegetation, land use, fire activity and climate at very high chronological resolution and precision. The goal is to gain uninterrupted evidence of prehistoric land use performance through time that complements fragmentary on-site archaeological records. High precision and resolution chronologies will allow matching off-site time series (e.g. land use, climate, erosion, eutrophication, fire, browsing) with the on-site archaeological record. A central question is: was the introduction of agriculture in Europe successful from the beginning (revolution hypothesis) or did the introduction of crops and animals from the dry and hot Near East need long-lasting adjustment to the cool and humid local climates (evolution hypothesis)? As ecologists we are also interested in assessing how the dense forests of Europe responded to anthropogenic disturbance connected to first farming, e.g. to slash-and-burn approaches. The joined environmental and societal evidence will allow to gain better insights into causes and effects of prehistorical societal changes, including climate vulnerability and resilience e.g. through technological innovations.
Mechanisms of RNA-guided genome editing in eukaryotes
ERC Consolidator Grant
Principal Investigator: Prof. Mariusz Nowacki, Institute of Cell Biology
The ERC "G-EDIT" project focuses on investigating the role of trans-generational RNA in the elimination of transposable elements.
Organic semiconductors interfaced with biological environments
ERC Starting Grant
Principal investigator: Prof. Natalie Banerji, Department for Chemistry and Biochemistry
Prof. Banerji's team uses spectroscopy to better understand organic bioelectronics. The term "bioelectronics" refers to the use of electronics in the biological context, for example electrodes that stimulate the nervous system, high-performance sensors that monitor the body's biological functions, or artificial retinas that restore eyesight. To overcome the inherent bio-incompatibility of metal or inorganic electrodes, organic materials such as films of conjugated polymers (a type of semiconducting plastic) can be used instead. In addition, the flexibility of these films allows them to adapt perfectly to surfaces such as the skin. To better exploit this new and very promising technology, we need to understand the interaction between organic semiconductor films and the biological aqueous medium. OSIRIS explores an original approach to the problem: ultrafast spectroscopy. This involves measuring light-matter interactions using extremely short laser pulses. For example, we use non-linear interactions between several of these light pulses to determine very specifically the molecular structure at the solid-liquid interface, or we explore the transport of charges and biological ions within organic films using far-infrared (terahertz) light. Moreover, we study how charges, produced by the illumination of the films, accumulate at the interface and stimulate neuronal activity, for artificial vision applications.
A Palaeoreanalysis To Understand Decadal Climate Variability
ERC Advanced Grant
Forschungsleitung: Prof. Stefan Brönnimann, Geographisches Institut
PALAEO-RA combines numerical modelling and mathematical techniques with historical documentary data and measurements, and dynamical analyses to produce a comprehensive reconstruction of global climate of the past six centuries. The "palaeo-reanalysis" will provide globally complete, three dimensional monthly fields of many variables and thus allows dynamical interpretations of past climate events.
Perception of Plant Volatiles
Principal investigator: Prof. Matthias Erb, Institute for Planct Sciences
The capacity to produce and perceive organic chemicals is essential for most cellular organisms. Plant leaves that are attacked by insect herbivores for instance start releasing distinct blends of herbivore-induced plant volatiles, which in turn can be perceived by non-attacked tissues. These tissues then respond more rapidly and more strongly to herbivore attack. One major question that constrains the current understanding of plant volatile communication is how plants perceive herbivore induced volatiles. Can plants smell danger by detecting certain volatiles with specific receptors? Or are other mechanisms at play? The key objectives of PERVOL is to address this question by 1) developing a new high-throughput plant volatile sampling system for genetic screens of volatile perception, 2) using the system to identify molecular mechanisms of volatile perception and creating volatile insensitive perception mutants to uncover novel biological functions of volatile priming. If successful, PERVOL will set technological standards by providing the community with an innovative and powerful volatile sampling system. Furthermore, it will push the field of plant volatile research by elucidating mechanisms of herbivore induced volatile perception, generating new genetic resources for functional investigations of plant volatile signaling and testing new potential biological functions of the perception of herbivore induced volatiles.
PROgrade metamorphism MOdeling: a new petrochronological and compuTING framework
ERC Starting Grant
Principal investigator: Pierre Lanari, Phd, Institute of Geological Sciences
When rock from the earth's crust sinks into the earth's interior and heats up, it undergoes a continuous transformation in which liquids are released. These play an important role in the formation of earthquakes, magmatism, the growth of the earth's crust or global geochemical cycles. There are various hypotheses about these interactions between rocks and liquids (fluid-rock interaction) in the earth's crust. However, it remains a major challenge to identify and quantify fluid flows in crustal rocks and to model their paths.
The aim of the "PROMOTING" project is to use computer simulations to understand how fluids influence the transformation of rocks in the Earth's interior at a depth of between 5 and 100 kilometres. To this end, the researchers are developing high-resolution imaging techniques for rock analysis and are creating the first computer model of metamorphosis (change in the mineralogical composition of a rock) to date, which integrates the movement of fluids from the rock plane to crustal sections. The results of the computer simulation can be compared with geochemical data from rocks all over the world.
Reconstruction of pollinator-mediated speciation by identification and substitution of causative mutations
ERC Advanced Grant
Principal investigator: Prof. Cris Kuhlemeier, Institute of Plant Sciences
A central aim of contemporary research on the origin of species is to identify the genes that are functionally differentiated between nascent species. Understanding the molecular-genetic basis of speciation will answer important questions that are of broad interest to geneticists, ecologists and evolutionary biologists. The RESPEC project will identify such “speciation genes”, map them onto conventional phylogenies and genetically reconstruct the process of speciation. Pollinator-mediated speciation is an attractive system to achieve these goals. Shifts in pollination syndromes are complex but are composed of distinct traits that can be studied individually. The advertising traits color and scent are known to be encoded by major effect genes, but for morphological traits no such information is available.
The Objectives of RESPEC are:
1. Substitute the four major-effect mutations for advertising traits in the hawkmoth-pollinated species, thereby creating an artificial mimic of the derived bee-pollinated species
2. Identify the major-effect genes that specify the morphological differences between a moth- and a hummingbird-pollinated species
3. Reconstruct the process of speciation during the shift from hawkmoth to hummingbird pollination
The identification and functional analysis of a complete set of major-effect genes will for the first time provide comprehensive molecular information about the process of speciation in a single system. The allele substitution experiments will demonstrate the importance of major-effect genes in speciation as opposed to Darwin’s view of evolution by gradual change. This has never been done before and was long thought to be impossible on theoretical grounds.
Stable Chromium Isotopes as a Productivity Tracer
ERC Consolidator Grant
Principal investigator: Prof. Samuel Jaccard, Institute of Geology
The overall concept of this proposal is to investigate the main biogeochemical processes modulating spatial and temporal changes in marine export productivity, and assess their role in regulating atmospheric carbon dioxide (CO2) concentrations, both under present conditions and in the geological past. The exchange of CO2 between the atmosphere and ocean interior mediated by the oceanic ecosystem is a pivotal mechanism modulating the global carbon cycle, and thus, a substantial driver of the Earth’s climatic evolution.
The overarching objective of this research proposal is to develop a novel proxy to trace changes in the global strength of the marine biological carbon pump (BCP) based on stable Chromium (Cr) isotopes. Despite its significance for the global carbon cycle, the BCP is still poorly constrained. This project will explore a tracer that has recently been developed to investigate the rise of atmospheric oxygen in the early history of the Earth and develop it thoroughly through a comprehensive, multidisciplinary calibration program and apply it to the much more subtle redox variations associated with organic matter remineralization in the ocean. The proposed approach includes phytoplankton culture experiments, water- column investigations and sedimentary analysis and will aim at elucidating the mechanisms governing the reduction of Cr and its associated isotopic fractionation. The proxy will subsequently be used to reconstruct export production variability in the past and assess its role in modulating glacial/interglacial climate oscillations. These past changes tended to be much slower than the current, anthropogenic change. Nonetheless, they can help to appraise sensitivities and point toward potentially dominant mechanisms of change. The observations gathered within the framework of this research program will enable refining the evolution of the marine carbon cycle and the rapidly declining buffering capacity of the ocean.
ERC Consolidator Grant
Principal investigator: Prof. Adrian Jäggi, Institute of Astronomy
The earth is subject to continuous environmental changes. Satellite observations provide the required data basis for being able to record such changes, to quantify them, to understand the underlying mechanisms and finally, to become aware of the societal challenge presented by the observed environmental changes. The objective of the project SPACE TIE is to develop new paths for the determination of a long-term stable reference frame, which is needed for a best possible recording of climate-relevant changes with amplitudes of 1 to 3mm per year, such as sea level rise. The project SPACE TIE is executed at the Astronomical Institute of the University of Bern (AIUB). The Bernese GNSS Software, which has been under development at the AIUB for many years, will play a key role for the high-precision analysis of the relevant satellite geodetic data.
Exploiting Synergistic Properties of Mesoionic Carbene Complexes: Teaching Rusty Metals Challenging Catalysis
ERC Consolidator Grant
Principal investigator: Prof. Martin Albrecht, Department of Chemistry and Biochemistry
The non-innocence of specific ligands in transition metal complexes is well-documented. For example, mesoionic carbenes engage in bond activation processes via reversible hydrogen capture. Such cooperativity between the metal center and the ligand flattens the potential energy surface of a catalytic reaction and hence rises the competence of the catalyst, thus entailing higher turnover numbers as well as the conversion of more challenging substrates. Likewise, such cooperativity is expected to enhance the catalytic activity of metal centers that are typically not considered to be catalytically very active, such as the ‘rusty’ first row transition metals (Mn, Fe, Ni). Surprisingly, however, this concept has largely been overlooked when designing catalytic transformations based on these Earth-abundant and low-cost transition metals. This project will exploit the synergistic potential of mesoionic carbenes as synthetically highly versatile and actively supporting ligands to access a new generation of sustainable high-performance catalysts based on Me, Fe, and Ni for challenging redox transformations such as dehydrogenative oxidations. Specificlly, 1,2,3-triazolylidenes, which support ligand-metal cooperativity through their mesoionic character, will be utilized for (transient) storage/release of protons and electrons. Apart from enabling challenging transformations — with obvious impact on synthetic methodology, energy conversion, and molecular electronics — this project will break into new grounds in catalyst design that will be widely applicable as a new paradigm. Furthermore, this project will capitalize on the unique synthetic versatility of triazolylidene precursors and the opportunity to combine different functional entities such as carbohydrates, surfactants, or dyes with an organometallic entity, thus providing a straightforward approach to new classes of multifunctional materials for application in therapeutics and diagnostics, or as smart surfaces.
Timing of Holocene volcanic eruptions and their radiative aerosol forcing
ERC Consolidator Grant
Principal investigator: Prof. Michael Sigl, Climate and Environmental Physics
Volcanic eruptions are a global natural hazard and have significantly shaped the history of the earth, the climate and mankind. In the near future, volcanoes somewhere in the world will continue to throw large quantities of climate-affecting gases into the atmosphere, possibly triggering droughts, crop failures and famines, as a glance into the past teaches us. In order to be prepared for the regional to global impacts of volcanic eruptions and to be able to estimate the probability of such extreme events, we need a continuous, complete time series of all climate-relevant volcanic eruptions of the past. There is no such series, but traces of all major eruptions in the eternal ice of Antarctica and Greenland are archived as in a history book. THERA aims to use ice cores to reconstruct global volcanism since the end of the last ice age in order to understand its influence on climate development in the past, present and future. Colossal volcanic eruptions are the only natural hazard of global proportions, along with impacts from asteroids and comets - and volcanic eruptions are many times more likely. The risk of this natural hazard comprises two factors which are independent of each other: on the one hand, the frequency of the natural hazard and, on the other hand, the possible extent of the damage caused by it. For the first time, both factors will be comprehensively investigated by THERA and will make it possible to quantify the risk for the global community. In the THERA project, innovative analytical methods are being developed that allow the location and height of the eruption column of past eruptions to be reconstructed. This allows conclusions to be drawn about the climate impact of volcanic eruptions.