You are invited to the New England Society for Microscopy's very first Virtual Fall meeting! The meeting will take place on September 24th via Zoom, consisting of two technical talks with Q+A session after each talk. It will consist of 2 technical talks and our Annual Business Meeting. The technical lectures will be delivered by Adam Martin from MIT and Austin Akey from the Harvard Center for Nanoscale Systems.
Please register (for FREE!) to receive the Zoom link. Log on at 6:45 pm, talks will begin at 7pm.
Meeting Schedule, September 24th
6:45 PM – Zoom Meeting will open
7:00 PM – Austin Akey (Harvard, Center for Nanoscale Systems)
Atom Probe Tomography: Three-Dimensional Mass Spec, One Atom At a Time.
7:40 PM – Networking Break-out Room Discussion
7:55 PM – Adam Martin (MIT)
Of Balloons, Washing Machines, and Eggs
8:35 PM – Closing Remarks
ABSTRACTS AND BIOS
Adam Martin
Of Balloons, Washing Machines, and Eggs
During the development of an organism, tissues are remodeled to change their shape and structure. This requires that cells generate forces that are coordinated between the cells of a tissue. How these forces are coordinated in a tissue to promote a physiological change is still unknown. We have developed live imaging approaches to visualize a range of different tissues that change shape in order to identify underlying principles that are involved in generating and coordinating forces. Here, I will discuss an important example of how a multicellular cluster gives rise to a single large cell, the fruit fly egg cell. First, I will show how the egg cell inflates like a balloon. Second, I will show how wave-like contractions are required to finish making the egg cell. We will discuss the combination of biophysical and biochemical mechanisms that contribute to egg formation.
Bio:
Adam Martin received his Ph.D. from UC Berkeley where he combined biochemistry, genetics, live imaging, and quantitative image analysis to demonstrate important roles for Arp2/3 complex mediated actin assembly and myosin motor activity to generate force during endoctyosis. As a postdoctoral fellow at Princeton University he extended his expertise to Drosophila gastrulation where live imaging of cell shape changes can be combined with genetics, mechanical manipulations, and computational analysis to study cellular forces that underlie tissue morphogenesis. Here, he discovered that apical constriction during Drosophila gastrulation occurs incrementally, via a ratchet-like contraction of an actin-myosin network. Pulsatile and incremental cell shape changes have now been identified in many other developmental processes that drive tissue morphogenesis. He started his own lab at MIT in January of 2011, where members rely heavily on imaging and quantitative analysis to analyze the spatial organization and dynamics of the cellular activities that transmit forces from the molecular to tissue scale. He is a recipient of the NIH Pathway to Independence Award and a Thomas D. and Virginia W. Cabot Career Development Assistant Professor of Biology. He was promoted to Associate Professor with Tenure in July 2018.
Austin Akey
Atom Probe Tomography: Three-Dimensional Mass Spec, One Atom At a Time.
Atom Probe Tomography (APT) is a three-dimensional, individual-atom composition mapping technique. Specimens are disintegrated atom-by-atom using a combination of high electric fields and voltage or laser pulses, causing individual ions to be ejected towards a position-sensitive detector with high time resolution. The resulting hit position, combined with the ion’s time of flight, allows single-Angstrom, single-atom time-of-flight mass spectroscopy to be performed over volumes containing hundreds of millions to billions of atoms. Recent advances in instrument design and automation have greatly expanded the field of materials systems and scientific questions that the technique can address, but many researchers are still unfamiliar with the tool and its capabilities.
Datasets can be processed and analyzed as highly-localized 1D composition measurements, 2D surface mapping over an arbitrary surface in three-dimensions, or full volumetric composition maps, allowing a wide variety of questions to be asked of a material. We present applications including: bulk composition fluctuation and clustering measurements; full 3D composition mapping of electronic devices; interface composition and roughness determination; composition mapping of nanowire and other quasi-one-dimensional structures; and surface and bulk composition of catalytic materials. We also discuss the importance of correlating other microanalysis techniques with APT and give examples of one-to-one correlative work. The development of correlative electron microscopy and APT specimen geometries have allowed otherwise unresolvable questions to be answered, and new work extends this into the realm of combined in-situ and ex-situ measurement of the structural and compositional evolution of materials. Finally, we will discuss future prospects for the technique and its application to the chemical and biological sciences.
Bio:
Austin Akey received his BA in Physics from Princeton University in 2006, and his PhD in Materials Science from Columbia University in 2011. His post-doctoral work was done in the groups of Professor Michael J. Aziz at Harvard University’s John A. Paulson School of Engineering and Applied Sciences, and of Professor Tonio Buonassisi at MIT. He is active in the fields of photovoltaics, hyperdoped silicon, and solidification of metastable materials, all of which benefit greatly from APT. Other interests include Focused Ion Beam technique development and instrumentation design. He is currently a Senior Scientist at the Harvard University Center for Nanoscale Systems.
