Florence GAZEAU (MSC Med Lab and IVETh integrator , 45 rue des Saints Pères, 75006 Paris, France)
Abstract : The clinical use of extracellular vesicles (EVs) will progressively become a reality in view of the number of ongoing clinical trials worldwide harnessing EV potency for tissue healing, resolution of inflammation (notably in Covid 19 patients), vaccination, drug delivery or cancer therapies, among others. EVs, encompassing a variety of cell shed nanoscale membrane vesicles (exosomes, ectosomes, microvesicles, OMV from bacteria…), are released by all cell types, either spontaneously or after induction, and circulate in all body fluids playing an active role in many physio- and pathological processes. EVs contribute to intercellular communication and immunomodulation via delivering bio-molecules like nucleic acids, proteins, and lipids that modify the recipient cells. Numerous biological effects of cell therapy rely on the cells’ secretome and, in particular on biomolecules contained in EVs, which are now studied as potential therapeutic agents to recapitulate a substantial part of the parental cell’s benefits, especially for stem cell-derived EVs. However the clinical translation of EV-based biotherapies face numerous challenges such as cost-effective large scale bioproduction compatible with a clinical use (GMP manufacturing), reproducibility from one batch to another and difficulties to isolate, characterize and identify the most potent nanosized subfractions from a complex and heterogeneous cell secretome. In addition, the technologies to engineer EVs in a pre-production or post-production step to convey specific proteins, nucleic acids, drugs and nanoparticles and improve or control their specific targeting and therapeutic activities are still in their infancy. In this presentation, we will present the breakthrough technologies for high throughput bioproduction, engineering and multimodal IA-assisted characterization of therapeutic stem cell-derived EVs, as well as EV delivery, that have been developed in our lab and led to the creation of two spin off. These technologies, based on multidisciplinary and physics-powered approaches (turbulence approach for high yield high throughput EV bioproduction and loading, EV delivery in a carrier gel, multimodal analysis tool box) are available for the industrial and academic partners on our innovation hub IVETh (https://iveth.u-paris.fr/) labelized as a national industrial integrator biotherapy-bioproduction in 2022
Speaker : Vikram Deshpande, University of Utah, USA
Abstract : Topological materials have burgeoned of late due to their implications for the fields of electronics, spintronics and quantum computing, among others. While their electronic properties are important in their own right, they can also couple in fascinating ways to the lattice. We have developed techniques to deform materials controllably and study their resulting electronic properties in-situ, while complementarily sensing the electronic ground state through the mechanical degree of freedom. In this talk, by way of introduction, I will first present purely electrical measurements on the prototypical topological material, the three-dimensional (3D) topological insulator (TI), wherein we hybridize Dirac cones of 3D TI surfaces controllably to realize the quantum spin Hall effect in the ultrathin limit. Then I will present our recent results applying the above-mentioned mechanical techniques to two different topological materials, namely twisted bilayer graphene (TBG) and the intrinsic magnetic topological insulator (MTI) MnBi2Te4, respectively. We are able to tune the Hofstadter’s spectrum of non-magic angle TBG and induce magnetism in non-magnetic correlated insulating states of magic-angle TBG using isotropic strain, for example, and detect various magnetic states and measure magnetoelastic couplings in the case of MTIs. Our advances present unique routes to tuning and sensing the parameter space of these exciting materials.
Contact : Stéphane BERCIAUD (berciaud@unistra.fr)
Speaker : Amélie JUHIN (Institut de Minéralogie, Physique des Matériaux et Cosmochimie (IMPMC). CNRS-Sorbonne Université)
Abstract : X-ray spectroscopies performed at synchrotron light sources, such as X-ray Absorption Spectroscopy and Resonant Inelastic X-ray Scattering are powerful tools to study complex materials, due to their chemical selectivity that allows disentangling the respective contributions of different atomic species. In this talk, I will show how the use of incident polarized x-rays (either linear or circular) can allow a deeper understanding of the electronic structure and reveal emergent properties, with a focus on remarkable magnetic nanomaterials: Single Molecule Magnets, bimagnetic nanoparticles, ferrofluids, ultra-thin nanowires. Moreover, I will illustrate how the combination of these spectroscopies with x-ray microscopy can provide valuable information with nanoscale spatial resolution, exemplified by recent results obtained on magnetotactic organisms.
Speaker : Benjamin Besga, ILM Lyon
Abstract : The aim of stochastic thermodynamics is to study small non-equilibrium systems subject to thermal fluctuations. Some results from this field will be illustrated using experiments carried out on opto-mechanical systems, mainly colloidal particles in an optical trap. Using non-equilibrium statistical physics will see how we can accelerate the natural dynamics of a system, shorten the mean first passage time on a target, or measure the forces acting on a non-equilibrium probe. Finally, we’ll ask how we can interrogate the quantum limit of these results by looking at the opto-mechanical coupling of a self assembled supercrystal of quantum dots in an optical trap.
On the program, small games during the aperitif: chips/beers/soft drinks. Then on the menu, knacks and potatoes salad and slightly longer games, ice cream and fruits for dessert. Veggie and vegan option will be proposed as well. Do not hesistate to bring your own favorite games with you and to make them us discover! In any case, a selection of boardgames will be at your disposal and we will take the time to explain you their rules. Happiness and friendliness will be the words of this event !
Participations fees are of 5 euros, or 3 euros if you are ADDEPT members (possibility to get the membership card during registration)
We are looking forward to playing with you!
Catherine Demangeat
Contact : Bertrand.Donnio@ipcms.unistra.fr
Abdelghani Laraoui (Department of Mechanical & Materials Engineering, University of Nebraska-Lincoln)
Abstract :
Magnetic microscopy based on nitrogen vacancy (NV) centers in diamond has become a versatile tool to detect magnetic fields with an unprecedented combination of spatial resolution and magnetic sensitivity, opening up new frontiers in biological [1] and condensed physics matter research [2]. In this seminar, I will present two examples of using NV magnetic microscopy in both scanning probe microscopy (SPM) and wide-field microscopy (WFM) geometries to study nanoscale magnetic phenomena in different materials. First, I will discuss NV-SPM measurements of antiferromagnetic (AFM) domains switching in Cr2O3 and B-Cr2O3 thin films and device structures [3, 4]. Cr2O3 is an archetypical AFM oxide that permits voltage-control of the Néel vector. In addition, boron doping increases Néel temperature from 307 K to 400 K and allows realizing voltage controlled Néel vector at zero applied magnetic field, a promising finding to AFM spintronics. Then, I will discuss NV-WFM measurements on individual Fe(Htrz)2(trz)](BF4)] (Fe triazole) spin-crossover (SCO) nano-rods of size varying from 20 to 1000 nm [5]. Fe triazole SCO complexes exhibit thermal switching between low spin (LS) and high spin (HS) states which are applicable in thermal sensors and molecular switches. While the bulk magnetic properties of these molecules are widely studied by bulk magnetometry techniques their properties at the individual level are missing. The stray magnetic fields produced by individual Fe-triazole nano-rods are imaged by NV magnetic microscopy as a function of temperature (up to 150 0C) and applied magnetic field (up to 3500 G). We found that in most of the nanorods the LS state is slightly paramagnetic, possibly originating from the surface oxidation and/or the greater Fe(III) presence along the nanorods’ edges [5].
References: [1] I. Fescenko, A. Laraoui, et al., Phys. Rev. App. 11, 034029 (2019). [2] A. Laraoui and K.
Ambal, Appl. Phys. Lett. 121, 060502 (2022). [3] A. Erickson, A. Laraoui, et al., RSC Adv. 13, 178-185 (2023).
[4] A. Erickson, A. Laraoui, et al., to be submitted to Nat. Mat. (2023). [5] S. Lamichhane, A. Laraoui, et al.,
ACS Nano 17, 9, 8694–8704 (2023).
Contact : Valérie Halté (valerie.halte@ipcms.unistra.fr)
Ricky Wong / Hong Kong Baptist University
Contact: stephane.mery@ipcms.unistra.fr
Dr. Veiko Karu Senior Project Manager for EIT Research and Development Projects from the Tallinn University of Technology (TalTech)
