Events

I am interested in the role that mechanical forces play in biology. Nature has exploited the intrinsic physical properties of polymers to build networks of biopolymer filaments and associated proteins, called the cytoskeleton, which can exert the tensile and contractile forces within cells required for cell functions such as cell motion and cell division. I will present results from experiments using reconstituted cytoskeletal biopolymers to investigate how these filaments define intracellular organization and mechanics.

Cells must not only generate forces to move and divide, but they must also be able to react to forces in their environment. This conversion of physical forces into biological responses is known as mechanotransduction. I will describe measurements of the response of living Escherichia coli bacteria to osmotic stress as a model for mechanotransduction, and of the mechanical properties of a cytoskeleton system reconstituted from purified components as a model for the behavior of cells.

Graduate and undergraduate student lunch with Dr. Maria Kilfoil

BaCuChF (Ch = S, Se, Te) materials are chalcogen-based transparent conductors with wide optical band gaps (2.9 – 3.5 eV) and a high concentration of free holes (1018 – 1020 cm-3) caused by the presence of copper vacancies. Chalcogen vacancies compensate copper vacancies in these materials, setting the Fermi level close to the valence band maximum. BaCuChF thin film solid solutions prepared by pulsed laser deposition (PLD) have tunable properties, such as lattice constants, conductivity and optical band gaps.

Biomagnetics: An interdisciplinary field where magnetics, biology and medicine overlap

Shoogo Ueno
Kyushu University/Teikyo University/The University of Tokyo

One of the current frontiers in magnetism is to understand the domain structure and the magnetization reversal
in nanometer sized particles. Explorations at these length scales have been aided by the development of new
magnetic imaging techniques [1] one of which is the magnetic force microscope (MFM), a variant of the atomic
force microscope. We have utilized the high resolution MFM (30 nm) we developed [2] to increase our
fundamental understanding of magnetism on this length scale. We will discuss the magnetic reversal of chains

FEI, Hillsboro is hosting a a day of exploration for OSU Physics grad and undergrad students by opening up its lab. The visit will provide insights into the possibilities for a career in physics, but it is not a recruiting function. Lunch and refreshments will be provided.

The plan is to introduce FEI to the group, provide presentations on the technology and how people with physics backgrounds contribute to FEI's business. Following that will be an

A microscopic understanding of the Ferromagnetic/Antiferromagnetic (F/AF) direct exchange coupling
or exchange biasing has been elusive for the over 45 years since its was discovered. In part, the almost
exclusive use of hysteresis loops to study the phenomenon has limited our understanding. A new experimental
technique was developed to study the exchange coupling between a ferromagnet and antiferromagnet [Appl.
Phys. Lett. 69,3932-3931 (1996)]. This new technique has enjoyed considerable success in explaining many

TBA

I will be speaking on ways to determine the fragmentation pressure threshold of ultrasound contrast agent microbubbles which has significant applications for contrast imaging, development of therapeutic agents and evaluation of potential bioeffects. Using a passive cavitation detector, this work evaluates fragmentation thresholds based on acoustic emissions from single encapsulated gas-filled microbubbles.

Despite research-based instructional strategies in introductory physics becoming increasingly widespread, how these strategies are implemented is not well understood. I will examine how educational innovations are taken up, take root, and transform educational practices. Data are analyzed from two case studies at the University of Colorado: the use of Peer Instruction (PI) and the use of the Tutorials in Introductory Physics (Tutorials).

The process of de-excitation of the actinides is a very important question in
both pure and applied science. In this dissertation the process was studied using
the neutrons emitted in coincidence with fission induced by the bombardment of
238U with 14.85 MeV deuterons. Neutrons can be emitted at multiple stages during
the de-excitation process, with each stage producing its own unique neutron spectrum.
The neutron spectrum in the lab frame is broken down into its constituent
components using kinematic corrections to place them in their own reference frame.

Howard Hui is a senior in physics at OSU who has crafted and unusual path through the curriculum while working as an intern at JPL and at Goddard.