Cal State L.A. logo and University Seal - Link back to main page
Physics & Astronomy Colloquium
Thursdays, 3:30 p.m.
Call us at: (323) 343-2100
Black and gold graphic bar

Winter Quarter 2013 Schedule

Biological Sciences Building, BIOS 244
Refreshments - 3:15 p.m., Colloquium - 3:30 p.m


Professor Victor Migenes
Department of Physics and Astronomy, Brigham Young University

" MASERs: A Very Special Window to the Universe "


Chuhee Kwon
California State University, Long Beach

"Online Social Homework Forum"

Abstract: The social homework forum is an online, face-book style form where students collaborate in small groups to solve problems.  A team of faculty in Physics & Astronomy and Science Education at California State University Long Beach has been developing the social homework system.  I will discuss the incubation and development of the program, how it looks, how physics faculty at CSULB has been using the system, and examples of student discussion.


Professor Moh El-Naggar
Department of Physics and Astronomy, University of Southern California

"Extracellular Charge Transport in Microbial Communities:
Physics Meets Microbiology"

ABSTRACT: Electron flow is the primary process by which energy and information are transmitted within both biological cells and man-made devices. But what if there was also a direct link allowing electron exchange between the living and non-living worlds? We now know that some anaerobic bacteria gain energy through extracellular electron transport to natural minerals or even synthetic electrodes that serve as electron acceptors for respiration outside the cells. In addition to the fundamental implications for physiology and microbial communication, a physics-based understanding of this extracellular respiration will impact the transmission of signals at hybrid iving/synthetic interfaces, potentially leading to new biomaterials and renewable energy technologies such as microbial fuel and electrosynthesis cells. But how can a bacterium transport electrons to a surface outside the cell? In contrast to solid-state systems (e.g. metals and semiconductors), where the charge transport physics is well understood, comparatively little is known about the physics of biological charge transport over long distances (cellular length scales). In this talk I will describe how bacteria organize redox sites on outer cell membranes, and along quasi-one-dimensional filaments known as bacterial nanowires, to facilitate long-range charge transport. The pproaches taken include microfluidic fluorescence assays, single-cell respiration measurements, scanning tunneling microscopy of redox molecules, and nanofabrication-enabled measurements of transport along individual bacterial nanowires produced by the bacterium Shewanella oneidensis MR-1. Based on these measurements, we propose that extracellular respiration is facilitated by an incoherent multistep charge hopping mechanism along redox chains. Our work suggests that bacteria use extracellular redox networks, akin to integrated circuitry, for energy distribution over large length scales; a breakthrough that challenges our traditional understanding of biological electron flow.


George Helou
Professor of Physics, California Institute of Technology

"A Statistical Model Of Black-Hole Growth And Star Formation in Galaxies"


Professor Ania Jayich
University of California, Santa Barbara

"Exploring Spin Qubits in Diamond for Quantum Sensing and Information"


Hamad Alyahyaei
University of California, Riverside

"Spintronic Devices Based on Graphene"


Kwan Ng
California State University, Los Angeles

"Imaging Through Turbulent Atmosphere Using Adaptive Optics"

    Search | Site Map | Campus Map | Campus Calendar | JFK Library | Campus Home Page | College Home Page

Last Update:Friday, March 1, 2013
Contact the Webmaster: