MPG

The structural anomalies of corpus callosum (CC) in patients are found highly-correlated with a wide range of disorders, e.g., epilepsy, autism, schizophrenia and mental retardation. However, it remains unclear about the causal contributions of CC-mediated functional changes to these disorders and exactly how the changes influence the local cortical circuitry. Lately, we have successfully combined fMRI with fiber optic mediated calcium recordings and optogenetics, i.e., multi-modal fMRI, to study the balance of excitation/inhibition in the barrel cortex in rats by pairing optogenetic corpus callosum activation with ascending thalamocortical activation. However, it remains challenging to maintain high sensitivity to the brain dynamic signal and better decipher CC-mediated unique cellular (neuron/astrocyte) or layer-specific contributions to the local cortical or global whole-brain fMRI signals. Therefore, the goal of this proposal is to optimize the multi-modal fMRI platform and to characterize the brain activity upon optogenetic callosal activation with higher spatial/temporal resolution using two cutting edge technologies, wireless amplified nuclear MR detector (WAND) and photonic crystal fiber (PCF). Previously, we have implanted a wireless RF coil into the rat body to achieve a high signal-to-noise ratio and spatial resolution for in vivo kidney imaging. The modified WAND will be incorporated into the multi-modal fMRI platform to achieve brain dynamic signal with enhanced sensitivity from the barrel cortex. Next, we will merge it with a novel PCF-based probe integrated calcium recording, optogenetic manipulation and fluid injection function. This proposal will merge the neuronal and astrocytic dynamic signals to the functional mapping, solve the challenges for CC study at multiple scales in the brain, enable novel applications of the multi-modal fMRI platform to better decipher the neuroglial interactions in normal and diseased animal models for future studies.

Two-dimensional crystalline materials exhibit exceptional physical properties and offer fascinating potential as fundamental building blocks for future two-dimensional electronic and optoelectronic devices. Transition metal dichalcogenides (TMDCs) are of particular interest as they show a variety of many-body phenomena and correlation effects. Key properties are: i) additional internal degrees of freedom of the electrons, described as valley pseudospin and layer pseudospin, ii) electronic many-body effects like strongly-bound excitons and trions, and iii) electron-lattice correlations like polarons. While these phenomena represent intriguing fundamental solid state physics problems, they are of great practical importance in view of the envisioned nanoscopic devices based on two-dimensional materials. The experimental research project FLATLAND will address the exotic spin-valley-layer correlations in few-layer thick TMDC crystals and TMDC-based heterostructures. The latter comprise other 2D materials, organic crystals, metals and phase change materials as second constituent. Microscopic coupling and correlation effects, both within pure materials as well as across the interface of heterostructures, will be accessed by time- and angle-resolved extreme ultraviolet-photoelectron spectroscopy, femtosecond electron diffraction, and time-resolved optical spectroscopies. The project promises unprecedented insight into the microscopic coupling mechanisms governing the performance of van der Waals-bonded devices.

With each newly detected exoplanet system, the planet formation theory is constantly gaining weight in the astrophysical research. The planets origin is a mystery which can only be solved by understanding the protoplanetary disks evolution. Recent disk observations by the new class of interferometer telescopes are challenging the existing theory of planet formation. They reveal astonishing detailed structures of spirals and rings in the dust emission which have never been seen before. Those structures are often claimed to be caused by embedded planets, which is difficult to explain with current models. This growing discrepancy between observation and theory forces us to realize: a novel disk modeling is essential to move on. Separate gas or dust evolution models have reached their limit and the gap between those has to be closed. With the UFOS project, I propose an unique and ambitious approach to unite gas and dust evolution models for protoplanetary disks. For the first time, a single global model will mutually link self-consistently: a) the transport of gaseous disk material, b) the radiative transfer, c) magnetic fields and their dissipation and d) the transport and growth of the solid material in form of dust grains. The development, performing and post-analysis of the models will initiate a new age for the planet formation research. The project results will achieve 1) unprecedented self-consistent precision to answer the question if those novel observed structures are caused by embedded planets or by the gas dynamics itself; 2) to find the locations of dust concentration and growth to unveil the birth places of planets and 3) to close the gap and finally unify self-consistent models of the disk evolution with the new class of observations. Only such advanced models combined with multi-wavelength observations, can show us the process of planet formation, and so explain the origin of the various of planets and exoplanets in our solar neighborhood and beyond.

The ability to search for information effectively and efficiently is central to academic and professional success. Understanding how children learn to seek information is a topic of immense importance for society, for parents, and for educators. Active learning – searching for information effectively and efficiently – requires the coordination of complex cognitive processes: the ability to generate, evaluate, test, and update one’s hypotheses about the world. Four skills critical for active learning develop between 3- and 10-years old: the ability to formulate effective questions from scratch, the ability to reason about uncertain events and to use that information to guide one’s search, the ability to adapt one’s search strategy based on feedback and task characteristics, and the ability to monitor the search process and stop searching when enough information has been collected. This project builds on this work to ask a critical but unanswered question: what factors support the development of these active learning skills and explain individual differences in them? Based on prior research, this project targets two factors: children’s cognitive skills and their socio-cultural environment. The first phase of the research is diagnostic and will explore using observational and correlational methods the associations and unique contributions of cognitive skills and socio-cultural input on children’s active learning skills. The second phase will use insights gained in Phase 1 to develop an intervention designed to boost children’s active learning skills. It will allow us to assess the causal impact of socio-cultural input and cognitive skills on the development of children’s active learning capacities by manipulating them experimentally. Because the acquisition of information seeking skills and the optimization of learning environments is critical to conceptual development in a variety of domains, findings promise to contribute both to psychological science and education.

This MSCA Reintegration proposal is aimed to study the heterogeneity of neuronal populations implicated in the maintenance of energy balance. Because of their location, neurons in the arcuate nucleus of the hypothalamus (ARC) integrate nutrient and hormonal signals carried in the blood. Then, they regulate downstream neuron’s activity in order to adapt food intake and energy expenditure. Deregulation of energy homeostasis can lead to obesity and diabetes, two of the major chronic diseases in the EU. AgRP neurons, an ARC population, have a prominent role in the regulation of food intake and systemic insulin sensitivity. They establish axonal projections with several brain areas and recent evidences show that each sub-circuit can have a specific function in the regulation of food intake and/or glucose homeostasis. For this fellowship I propose to use an innovative experimental approach to investigate a specific novel AgRP neuronal subpopulation, characterized by the expression of the UDP-receptor, P2Y6, as a first step to unravel the heterogeneity of the total population. Although P2Y6 activation increases short-term food intake, its effects on glucose homeostasis are still unknown. I plan to combine new recombinase technologies with state of the art techniques to genetically identify the AgRP, P2Y6 subpopulation and then: 1) characterize their in vivo dynamic response to physiological activators; 2) map specific AgRP+, P2Y6+ sub-circuits and dissect their role in each facet of energy homeostasis; and 3) investigate new molecular markers, as possible drugable targets. Results from this project will unveil new aspects of neuronal heterogeneity that participate in the regulation of energy homeostasis and will contribute to design new strategies to curb the actual obesity trends. The completion of this MSCA fellowship represents an exceptional opportunity to reinforce my professional maturity and to develop my independent research line.