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TREND Fair 2011

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August 3, 2011

The TREND Award for Best Overall Project was awarded to Dustin Anderson and Ari Tenzer

On this page... TREND 2011 Presentations


Winners of TREND Fair 2011

Best Overall Project: Dustin Anderson and Ari Tenzer for their project titled "Multiscale Oscillator Interactions in Large Networks of Networks."

The TREND runner-up for Best Overall Project went to Zack Lasner for his project titled "Charge Buildup in Sandstorms."

trend photoMultiscale Oscillators Interactions in Large Networks of Networks

(Presentation, Poster)

Dustin Anderson, Carleton College
Ari Tenzer, Washington University in St. Louis

Advisors: Professor Edward Ott, Professor Thomas Antonsen, Assistant Professor Michelle Girvan, and Gilad Barlev

Networks of coupled oscillators occur commonly in physics, biology, and neuroscience. The Kuramoto model, which formalizes and explains the phenomenon of synchronization in such networks, is a useful tool for understanding their dynamics. We explore an extension of the Kuramoto model in which each oscillator acts as part of a community. Oscillators within a community synchronize and act as a coherent unit, while oscillators in different communities have a repulsive effect on one another. We characterize the equilibrium configurations of this kind of oscillator network and determine which configurations are stable. We also investigate how these equilibria change when the oscillator groups are allowed to have different natural frequency distributions.

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trend photoElectromagnetic Wave Chaos in 3D Cavities

(Presentation, Poster)

Sabrina Atienza, University of California - Berkeley

Advisor: Dr. John Rodgers

We investigate the applicability of the Random Coupling Model (RCM) to electromagnetic (EM) fields within general complex cavities. In this experiment, we measure the statistics of the scattering and impedance matrices of a two-port, three-dimensional cavity, not known to produce wave chaos but of sufficient complexity to randomize steady-state EM field distributions. Rotation of an aluminum perturber generates unique realizations of EM field distributions. We demonstrate that RCM provides a valid statistical description of our sufficiently complex cavity given time reversal symmetry (TRS) or TRS broken, thereby validating the utility of RCM in predicting semiclassical wave-chaotic structures.

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trend photoCesium Evaporation Rate on Tungsten Photocathodes

(Presentation, Poster)

Ameerah Jabr-Hamdan, Clarkson University

Advisors: Professor Patrick O'Shea, Dr. Eric J. Montgomery, Blake Riddick, and Peter Zhigang Pan

Photocathodes are necessary for high peak power free electron lasers and other accelerator applications. The optimal photocathode has a long lifetime and high quantum efficiency. Knowledge of the evaporation rate of cesium on tungsten is important for calculating the lifetime of tungsten dispenser photocathodes and minimizing cesium contamination of any system in which the photocathodes are used. Maintaining a cesium coating increases the lifetime of the photocathode, while allowing a lower work function than that of the metals the cesium rests on. In this work, a submonolayer coating of cesium was evaporated from a tungsten dispenser photocathode, after a shutter was built to shield different elements in the vacuum chamber as needed.

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trend photoTwo-Dimensional Spatiotemporal Communication

(Presentation, Poster)

Kristi Engel

Advisors: Professor Rajarshi Roy, Associate Professor Thomas Murphy, and Aaron Hagerstrom

We explore the idea of two-dimensional spatiotemporal communication using a pair of nonlinear electro-optic feedback loops based on liquid crystal spatial light modulations (SLM) and digital cameras, which operate at 1550 nm. The device exploits the synchronization of spatiotemporal chaos to encode and decode messages in the form of two-dimensional images. We linearly couple an experimental ring containing a SLM to a numerical model, allowing them to achieve synchronization. By utilizing this synchrony, the model is able to recover data hidden in the chaotic behavior of the optical ring. Mathematical modeling of spatiotemporal array synchronization was also performed using MATLAB. In both systems, the error effects of different topology and parameter mismatch in the encoding-decoding process were evaluated.

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trend photoCharge Buildup in Sandstorms

(Presentation, Poster)

Zack Lasner, Pomona College

Advisors: Professor Daniel Lathrop, Donald Martin, Dr. Daniel Zimmerman, Hansen Nordsiek, and David Meichle

We experimentally investigate triboelectric charging, a poorly understood process by which insulators of identical material become statically charged upon contact. Dry sand is shaken in a cell with metal plates on two opposite walls, with voltage spikes across the cell observed when a charged particle collides with the conducting walls and discharges. The effect of externally applied electric fields is quantitatively investigated to elucidate observations that external electric fields significantly contribute to the charging process in natural sandstorms.

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trend photoRecording Sounds in Superfluid 4He at 2.17 Kelvin and Below

(Presentation, Poster)

Patrick M. McDonough, University of Maryland

Advisors: Professor Daniel Lathrop, Enrico Fonda, and David Meichle

4He starts the transition to a superfluid at 2.17 Kelvin. Quantized vortices are an experimentally verified feature which explains some of the exotic properties of superfluid. An observed process of these vortices is called reconnection which occurs when two vortices cross. In this manner, two horizontally moving vortices will come in contact and form an "X." Then the "X" will snap into two vortices moving vertically away from each other similar to rubber bands snapping apart from each other. I have acoustically recorded this process using a Microelectromechanical systems microphone. These recordings are being analyzed to isolate the sound of one reconnection.

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trend photoParticle Image Velocimetry of Optically Stretched Cells

(Presentation, Poster)

Samuel Engel, Columbia University

Advisors: Associate Professor Wolfgang Losert, Eleanor Ory, and Matthew Kretschmer

One approach to better understanding cancer metastasis is to study the dynamics of a cancer cell. An optical stretcher aims two lasers at opposite ends of a cell, causing the cell to expand along the axis of the beams. Observing a cell's stretch and recoil gives information about that cell. Previous studies of optical stretcher data have focused primarily on cell boundaries, but internal shifts could yield equally valuable insights. Particle Image Velocimetry (PIV) can be used to produce velocity data about a moving cell's interior as well as its edge. This work aims to analyze chemically-treated and optically-stretched cancer cells using PIV.

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trend photoUsing Morphology to Characterization LAT Protein Patterns

(Presentation, Poster)

Brian Slusher, The Ohio State University

Advisors: Associate Professor Wolfgang Losert and Joshua Parker

With development of the photoactivated localization microscopy (PALM), it is now possible to image the spatial distribution of proteins in vivo with approximately 10 nm resolution. From these images, one can generate point distributions of the proteins. The proteins studied as examples here, LAT, are essential for function and differentiation of T-cells and are of great interest in immunology. A standard approach to characterizing the protein localization patterns would be second-order functions, such as the pairwise correlation function, g(r). But, these techniques are by nature insufficient for manifesting multiparticle clustering dynamics. Morphologically-based characterization has had recent success in astronomical applications, where the topological structure of the patterns is characterized using Minkowski functionals. This summer, we plan to perform Minkowski functional analysis on PALM-generated point patterns of LAT proteins, which we have acquired from Eilon Sherman at NIH. The goal is to investigate how they may redistribute when the host T-cell has been activated. We will also characterize generated point patterns at varying number intensities to see exactly how the functionals change for different clustering scales. Through this analysis, we hope to shed light on how the proteins interact during activation.

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trend photoEstimation Methods in a Magnetic Marking System for Cancer Surgery

(Presentation, Poster)

Maia Werbos, University of Maryland

Advisor: Professor Wesley Lawson

A magnetic marking system for use in cancer surgery is being tested. In this system, a small permanent magnet is inserted into the affected region before surgery; during surgery, a device using an array of magnetic sensors detects the presence of the magnet and guides the surgeon in locating it. This method can make surgery safer and quicker, but the precision and usefulness of the device need to be improved. In this project, mathematical methods for estimating different parameters that will assist the surgeon, such as distance to the magnet and angle of incidence to the magnet, are proposed and tested in simulations of the magnet's generated field.

Pictures at the TREND Fair 2011 were taken by Carrie Anne Hilmer, Electrical and Computer Engineering.