Princeton's Nathaniel Fisch
| Number 169
| October 18, 2004
HIV dementia mechanism discovered
A brain-imaging study at DOE's Brookhaven Lab shows that human immunodeficiency virus (HIV) damages dopamine-associated brain cells in patients with HIV dementia—a type of cognitive decline in the later stages of HIV infection. The brain images, obtained with positron emission tomography (PET) at Brookhaven's Center for Translational Neuroimaging, reveal that patients with HIV dementia have fewer dopamine transporters— proteins that help to recycle the neurotransmitter dopamine—than HIV-negative subjects or HIV-positive patients without dementia. These findings may lead to new, more effective therapies. Future studies will also look at whether treatments to suppress HIV lead to recovery of the dopamine system.
[Karen McNulty Walsh, 631/344-8350;
New method for medical implants, chemical detection
In research that may lead to revolutions in bio-sensing and biomedical implants, scientists at DOE's Argonne National Laboratory have pioneered a process to affix organic molecules to the surface of a thin layer of diamond. Biomolecules can be harnessed for a broad range of uses from detecting anthrax spores to helping diabetics monitor their blood sugar. Argonne researchers have developed an innovative way to construct hybrid organic-inorganic interfaces based on conducting diamond thin films, allowing biomolecules such as proteins to be anchored to the surface while preserving their functionality. Research funding was provided by DOE's Office of Science.
[Catherine Foster, 630/252-5580;
Theory offers new view of the nucleus
Scientists have known for more than 30 years that protons and neutrons are built of quarks and gluons. But they interpret data from experiments on the nucleus with "effective theories" which ignore this internal structure for the sake of simplicity. Now a new study from DOE's Jefferson Lab, together with the CEA in France, proposes a theory that for the first time incorporates the dynamical changes in the quark-gluon structure of protons and neutrons in the nucleus. Published Sept. 23 in Physical Review Letters, it is a first step towards a truly fundamental theory of nuclear structure.
[Kandice Carter, 757/269-7263;
Ames research a boon to bioanalysis
Studies of individual enzyme molecules by Edward S. Yeung, director of the Chemical and Biological Sciences Program at DOE's Ames Laboratory, define the most sensitive level of detection of biomolecules and reveal that the catalytic activity of the same enzymes differs. The work has inspired many single-molecule studies in other research groups and promises to impact molecular modeling, drug design and catalytic studies. Testimony to Yeung's prolific record of scientific accomplishments fundamental to the field of bioanalysis, is his selection as the first recipient of the newly created Ralph N. Adams Award in Bioanalytical Chemistry, which will be presented to him at the 2005 Pittsburgh Conference on Analytical Chemistry and Applied Spectroscopy.
[Saren Johnston, 515/294-3474;
PNNL to unlock salmonella and pox proteomes under biodefense project
DOE's Pacific Northwest National Laboratory has received a $10.3 million biodefense contract from the National Institute of Allergies and Infectious Agents (NIAID) to identify the proteins that regulate the bacteria that cause salmonella poisoning and typhoid fever, and the monkey pox virus. Besides monkey pox, which serves as a close viral analog to deadly smallpox, two species from the genus Salmonella will be examined: typhimurium (which causes food poisoning) and typhi (typhoid fever). These pathogens, which spread quickly and are not easily combated with conventional drugs, could lead to major epidemics if enlisted by terrorists. NIAID is banking that determining which microbial proteins interact with which human host cells will point drug designers toward quick and effective treatments during an outbreak.
[Bill Cannon, 509/375-3732;
Princeton's Fisch provides
needed fusion insight
Nathaniel Fisch, a Princeton University professor and theoretical physicist at the U.S. Department of Energy's Princeton Plasma Physics Laboratory (PPPL), has persevered in finding novel ways to use plasma waves to produce electric current. Plasma is a hot, ionized gas that serves as the fuel for nuclear fusion. Fisch's patient efforts led to his discovery of new ways of driving current by injecting radio waves into the plasma. These wave-induced currents can enable fusion reactors, called tokamaks, to operate continuously, which is necessary for an economical and practical fusion reactor.
PPPL Director Rob Goldston said, "Professor Fisch's analyses of techniques to use radio waves to drive electrical currents in plasmas are as elegant and insightful as they are practical. His theoretical work and close collaboration with the experimentalists opened the way for a wide range of experiments and further analyses, and led to a substantial field of research on current-drive in toroidal plasmas. Indeed, sustainment of currents using radio waves may prove to be an essential ingredient in the steady-state operation of fusion power systems."
Fisch specializes in theoretical plasma physics with applications to controlled nuclear fusion, plasma devices, lasers, and astrophysics. In addition to his contributions to the field of plasma physics, he has played an influential role in shaping graduate education in plasma physics. At Princeton University, he is Director of the Program in Plasma Physics, which is widely recognized as one of the world's premier graduate programs in plasma physics. At PPPL, he is Associate Director for Academic Affairs and Head of the Laboratory's Hall Thruster Experiment.
On November 8, Fisch will receive one of seven 2004 E. O. Lawrence Awards for his discovery of ways to use plasma waves to produce electric current. He is a Fellow of the American Physical Society and is the author or co-author of more than 200 research papers. He has been granted nine U.S. patents. He received a Guggenheim Fellowship in 1985, the 1992 APS Award for Excellence in Plasma Physics, and a Department of Energy Bronze Medal for Outstanding Mentor 2002.
Fisch was born in 1950 in Montreal, Canada. He grew up in Brooklyn, New York City. He studied Electrical Engineering and Computer Science at the Massachusetts Institute of Technology, earning his B.S. degree in 1972, his M.S. degree in 1975, and his Ph.D. degree in 1978.
Submitted by DOE's
Princeton Plasma Physics Laboratory