Dear colleagues,=0A= =0A= The *Chaire de la Vallee Poussin* lectures by professor Ieke Moerdijk will = take place in Louvain-la-Neuve at the Institut de Recherche en Mathematique= et Physique (in room CYCL01) from 6 to 9 September 2022.=0A= =0A= The general title of the lectures is *Trees in Algebra and Geometry*. The p= rogramme will be as follows (see=A0https://uclouvain.be/fr/instituts-recher= che/irmp/chaire-de-la-vallee-poussin.html =A0for further details) =0A= =0A= - Tuesday 6 September, 4.15 p.m. (inaugural lecture): Some interactions bet= ween Algebra and Geometry=0A= =0A= - Wednesday 7 September, =A04.15 p.m.: Operads, trees and duality=0A= =0A= - Thursday 8 September, 11 a.m.: Comparison of different E_n operads=0A= =0A= - Friday 9 September, 9.30 a.m.: Profinite completion of Quillen model cate= gories=0A= =0A= There will be a *Workshop on Categories and Topology* on Friday 9 September= . The following invited speakers have accepted to give a talk at the Worksh= op (the precise programme will be communicated later on):=0A= =0A= Pedro Boavida (IST, Lisbon)=0A= John Bourke (Brno)=0A= Sandra Mantovani (Milan)=0A= Aniceto Murillo (Malaga) =0A= Emily Riehl (Johns Hopkins)=0A= Jerome Scherer (EPFL)=0A= =0A= If you are interested in attending these events, please write an email to M= me Carine Baras ( carine.baras@uclouvain.be ) to register, by August 15th. = The registration is free.=0A= =0A= We have booked a limited number of rooms at the Hotel Ibis Style in Louvain= -la-Neuve (at a special rate), please let Mme Baras know at your earliest c= onvenience in case you are interested.=0A= =0A= With best regards,=0A= =0A= Marino Gran,=A0Pascal Lambrechts, Tim Van der Linden, Pedro Vaz and Enrico = Vitale=0A= [For admin and other information see: http://www.mta.ca/~cat-dist/ ]