Speaker: Kaelyn Sumigray, YaleHost: The Chipperfield CommitteeTitle: "Collective cell dynamics in epithelial morphogenesis"The Biology Colloquium is a weekly seminar held throughout the academic year — featuring distinguished speakers in many areas of the biological sciences from universities and institutions worldwide. More information on speakers, their affiliations, and titles of their talks will be added as available. Unless otherwise stated, the Colloquium will be held live in Stata 32-123 (Kirsch auditorium) Contact Margaret Cabral with questions.

Title: TBD

Preparing for a research talk, investor pitch, or interview? Eager to polish your three-minute thesis video, podcast, or public talk? In this NEW, six-session workshop series, learn to refine your speaking and presentation skills across a range of contexts. Whether your audience is intimate or enormous, expert or novice, we will help you find strategies to capture and keep their attention. Each interactive session will invite you to implement tips on tailoring your content, delivery, and visual aids to develop your confidence, clarity, and charisma. At the end of six meetings, you will have solid advice and experience with introducing yourself and your topic, tailoring your talk to diverse audiences, structuring your content, streamlining your flow, practicing effectively, and fielding questions.Session 1: Tue, April 1, 4:00-5:30 p.m. First Impressions Session 2: Thu, April 3, 4:00-5:30 p.m. Engage Your Audience Session 3: Tue, April 8, 4:00-5:30 p.m. Structure Your Presentation Session 4: Thu, April 10, 4:00-5:30 p.m. Tell Your Story Session 5: Tue, April 15, 4:00-5:30 p.m. Enhance Your Presentation Session 6: Thu, April 17, 4:00-5:30 p.m. Finish Strong: Conclusions and Q&A

Speaker: David Lee (MIT) at 4:30 PM 2-131 (special time and location)Title: On the p-local homotopy type of truncated Brown—Peterson spectraAbstract: It is a result of Adams and Priddy that BSU admits a unique infinite loop space structure after localization at a prime p. On the way to proving this statement, they prove that the p-localized connective complex K-theory spectrum ku(p) is characterized by its 𝔽p-cohomology as a Steenrod module. I will talk about a generalization of this part to truncated Brown—Peterson spectra BP⟨ n⟩ at odd primes, which can be thought of as higher chromatic analogues of the connective complex K-theory. In particular, since the 𝔽p-cohomology depends only on the p-completion, a part of this result is that we can recover the p-local homotopy type of BP⟨ n⟩ from its p-completion. Finally, I will describe some applications and open questions, including the status of the problem at p = 2.

Speaker: Vasily Dolgushev (Temple University)Title: The action of Grothendieck-Teichmueller (GT) shadows on child's drawingsAbstract:Grothendieck-Teichmueller (GT) shadows can be thought of as approximations of elements of the mysterious Grothendieck-Teichmueller group GT introduced by V. Drinfeld in 1990. GT-shadows are morphisms of a groupoid GTSh whose objects are certain finite index normal subgroups of the Artin braid group. The groupoid GTSh is closely connected to group GT and to the absolute Galois group $G_Q$ of rational numbers. GTSh acts on Grothendieck's child's drawings and this action is compatible with those of the groups $G_Q$ and GT. In my talk, I will present the hierarchy of orbits of child's drawings with respect to the actions of $G_Q$, GT and GTSh, give selected examples and say a few words about future directions of this research. This talk is loosely based on my paper "The Action of GT-Shadows on Child's Drawings" (J. of Algebra, 2025). In many respects, the exploration of the action of GT-Shadows on child's drawings is inspired by a paper written by D. Harbater and L. Schneps in 1997.