Hands-On Research

Sponsored by The Abdus Salam International Centre for Theoretical Physics (ICTP, Trieste, Italy)

Founding Directors: Rajarshi Roy, Kenneth Showalter, and Harry L. Swinney

Soft matter

Prof. Eric Weeks and Xia Hong (Emory University) and Yang Li (Shanghai Jiao Tong University)

Why do butter, lotions, and creams act like both liquids and solids? What causes foam to flow differently from paste? These types of questions are at the heart of soft condensed matter, the study of materials with both fluid and solid properties (often called "complex fluids"). In this module, we will use a microscope to observe the flow of an emulsion, made of oild drops in water.



Colloids

Prof. Lei Xu and Dr. Peng Tan (The Chinese University of Hong Kong)

At first glance, most solids seem rigid and hard to deform. However, wehn zooming in to inspect their basic building blocks - atoms, they are all constantly vibrating around equilibrium positions. Using micron sized particles as large "atoms", we build 2D colloidal systems whose motions can be directly visualized. From these motions, the normal modes can be extracted at single-particle level.



Cellular motility

Prof. Erin Rericha and Jie Zhao (Vanderbilt University) and Lin Huang (Shanghai Jioa Tong University)

The classic model of rapid ameboid cell migration in two dimensions describes a cell moving forward by extending protrusions in the front and using muscle-like contractions to retract the back. How the cell establishes where to protude and where to contract, cell polarity, is an active area of research at the intetrface of biology and nonlinear dynamics. In this module we will use time lapsed fluorescent microscopy to record a movie of the migrating cell and extract the cell shape with custom interface finding matlab code.



Microcontrollers

Prof. Thomas E. Murphy, Hien Dao, and Caitlin Williams (University of Maryland) and Hao Xu (Shanghai Jioa Tong University)

Digital microprocessor systems are ubiquitous in consumer electronics today, and are found in automobiles, computers, embedded systemts, handheld devices, and smart sensors. In this sesison, participants will learn some simple techniques for programming and controllingg a simple microcontroller board, the Arduino.



Chemical oscillators

Dr. Mark Tinsley, Prof. Kenneth Showalter, and Simbarashe Nkomo (West Virginia University), and Zhiqin Xu (Shanghai Jioa Tong University)

Populations of coupled oscillators are common in physical, chemical, and biological systems. The Belousov-Zhabotinsky (BZ) reaction proves to be a particularly amenable system for for the study of large populations of oscillators. In this module we will analyze the phase distributions of microbeads exhibiting periodic oscillations or stationary state behavior and examine how density influences local coupling and synchronization.



Chua's circuit

Dr, Gautham C. Sethia, and Mitesh S. Patel (Institute for Plasma Research, India) and Gaomeng Wang (Shanghai Jioa Tong University)

The dynamics of single and coupled nonlinear electronic circuits will be explored through both simulation (using ORCAD-PSPICE) and experiments. Phenomena such as period doubling, period adding, and bifurcation routes to chaos will be studied using a digital oscilloscope and will be compared to numerical simulations conducted using XPPAUT.



Fluid instabilities

Professor Harry Swinney, Dr. Bruce Rodenborn, and Dr. Likun Zhang (University of Texas) and Yorquant Wang (Shanghai Jioa Tong University)

Flow between concentric independently rotating cylinders has become a paradigm for the study of instability in fluid dynamics and other systems. Participants will use an inexpensive digital camera (webcam) to make moveis of the flow patterns and the will use Matlab to analyze the movies to characterize dynamical states of the flow from simple periodic states to chaos.



Boolean networks

Prof. Dan Lathrop and David Meichle (University of Maryland) and Haiwei Du (Shanghai Jioa Tong University)

This lab session will focus on the dynamics of elecronic boolean circuits. We will explore unusual arrangements of logic gates, relative to normal electrical engineering circuits, that incorporate loops in more general topological connections. In this module we will build logic circuits and high-speed elecetronic diagnostics, and will deploy the scientific method in our study of these dynamics.



Locomotion dynamics

Prof. Daniel I. Goldman, Nick Gravish, and Sarah Sharpe (Georgia Tech), and He Li (Shanghai Jioa Tong University)

Organisms from six legged cockroaches to two legged humans display similar dynamics when walking and running. In this module we will mease level locomotion dynamics during walking and running of a large biped (a human) to illustrate concepts in biomechanics. Forces will be measured using a custom force plate and kinematics measured using a low cost high speed camera and Matlab.



Modeling

Professor Mark Shattuck (City College of New York), David Cai (Shanghai Jioa Tong University), Qi Ouyang (Peking University), Brian Hunt (University of Maryland), and Brian Storey (Olin College, Massachussetts)



Chaos in optics

Professors Raj Roy (University of Maryland), Xiaowen Li (Beijing Normal University), Aaron Hagerstrom and Jiang Xu (University of Maryland), Yuanlin Zhen (Shanghai Jioa Tong University)

A spatial light modulator (SLM) that utilizes 480x320 micromirrors for spatiotemporal modulation of a light beam is incorporated as part of a feedback loop composed of a laptop computer and a digital camera. The compuer updates the state of the SLM based on input from the camera. Our goal is to explore the spatiotemporal dynamics that may be generated through different feedback algorithms based on models of excitable media.



Biological tissue

Dr. Eva-Maria Schoetz and Sofia Quinodoz (Princeton University), Kristine Glaubner (University of California, Irvine), and Xiao Chen (Shanghai Jioa Tong University)

The interplay of cell signaling plays a major role for tissue regerneration and pattern formatino during embryonic development and regeneration. In this session, we will study mechanical oscillations that occur during regeneration and locomotion in two popular regeneration model systems: hydras and planarians. Using time lapse imaging and image analysis in Matlab, we will study quantitatively these oscillations to gain a better understanding of their biological origin.



Turbulence

Professor Michael Schatz, Balachandra Suri, and Jeffrey Tithoff (Georgia Tech), and Xiang Wu (Shanghai Jioa Tong University)

Turbulent flows play a central role in many natural and technological processes; developing a fundamental understanding of turbulence stands as one of the greatest challenges in physics. This Hands-on Session will explore the problem of turbulence in table-top experiments on two-dimensional (2D) flows. The simple design of the experiments will enable Hands-on participants to learn quickly essential techniques that permit exploration of scientific questions at the forefront of turbulence research.