Download high resolution photos of Walter Chazin, Raymond DuBois, Leonard Feldman and Dennis Hall.
NASHVILLE, Tenn. ñ Four Vanderbilt scientists ñ Walter J. Chazin,
Raymond N. Dubois Jr., Leonard C. Feldman and Dennis G. Hall ñ have
been elected as fellows of the American Association for the Advancement
of Science (AAAS), an honor bestowed upon them by their peers. They are
being honored for contributions to research that runs the gamut from
determining the atomic structure of proteins to paving the way for
improved treatments of digestive diseases including colon cancer, from
investigating the atomic structure of materials to providing new
insights into the fundamental nature of light.
They are among 308 scientists from around the country who have been
elevated to this rank because of their efforts to advance science or
its applications that are deemed scientifically or socially
distinguished. New fellows will be presented with an official
certificate and a gold and blue rosette pin on Saturday, Feb. 19, at
the 2005 AAAS Annual Meeting in Washington, DC.
Chazin was cited for "his important contributions to the chemistry
and structural biology of proteins." He is the director of the Center
for Structural Biology and Chancellor’s Professor of Biochemistry and
Physics. A nuclear magnetic resonance (NMR) spectrography expert, he
was recruited in 1999 to build Vanderbilt’s NMR presence in the context
of a more comprehensive structural biology center. The center is now
used by researchers across campus to determine the structure of
biological molecules at atomic resolution.
The Chazin laboratory has made significant progress in working out
the underlying basis for the concerted action of multiple proteins that
gather together to read the information in human genomes and help
maintain their accuracy. He and his colleagues are applying the basic
approach that they developed for this purpose to study defects in
proteins that lead to specific cancers, cardiac arrhythmias and
diabetes-induced atherosclerosis.
In addition to serving as director-at-large of Vanderbilt’s NMR
centers, Chazin is an Ingram Professor of Cancer Research and director
of the Molecular Biophysics Training Program. He came to Vanderbilt
from the Scripps Research Institute at the University of California,
San Diego.
DuBois was cited for "outstanding contributions to the field of
cancer protection and digestive disease research and for the discovery
of the role of the cyclooxygenase-2 enzyme in colorectal
carcinogenesis." DuBois ñ Mina Cobb Wallace Professor of
Gastroenterology and Cancer Prevention; professor of medicine;
professor of cancer biology and director of the Division of
Gastroenterology ñ is recognized internationally for his groundbreaking
contributions toward understanding the role of cyclooxygenase-2 (COX-2)
in cancer and the potential for COX-2 inhibition in preventing and
treating cancers.
The COX enzymes generate prostaglandins, ubiquitous molecules that
are involved in a host of physiological processes, including pain and
inflammation. DuBois’ lab was the first in the world to report that
COX-2 expression is elevated in human colorectal cancers, and
inhibitors of the enzyme blocked the growth of colorectal cancer cells
that express COX-2. In 2000, an international team of researchers,
including DuBois, reported that the use of Celebrex ñ the first
selective COX-2 inhibitor ñ led to a significant reduction in the
number of polyps in patients with familial adenomatous polyposis, an
inherited condition characterized by multiple colon polyps that usually
become malignant. The landmark finding, published in The New England
Journal of Medicine, opened the floodgates for studies aimed at
preventing other cancers by blocking production of prostaglandins.
DuBois and his colleagues continue to pursue the precise mechanisms
by which COX-2-derived prostaglandins promote tumor development in the
colon. The ultimate hope is to identify other targets for drugs that
may be even more effective at interfering with this process.
Feldman was cited for his "innovative contributions to the use of
ion scattering as a tool for materials analysis and for the
understanding of the structure of interfaces." Before moving to
Vanderbilt in 1996, Feldman spent 29 years as a researcher and
department head at Bell Laboratories under AT&T and Lucent
Technologies management.
Throughout his career, Feldman has specialized in applying
techniques from nuclear physics to study the structure of materials and
the nature of the interfaces that form between different materials.
Much of his work has involved the study of the interface between
silicon and silicon dioxide, which has been called the "heart of the
semiconductor revolution" because of its crucial role in the
architecture of computer chips and other solid state electronic
devices.
He holds 20 patents and has authored some 350 publications and
co-authored three books on materials physics. His most important patent
involves the use of nitrogen gas in the manufacture of silicon/silicon
dioxide devices. A typical integrated circuit has an insulating layer
of silicon dioxide separating its silicon and metal layers. The
presence of nitrogen gas keeps the metal layer from poisoning the
silicon as the oxide layer is made thinner and thinner. This procedure
has become a standard practice in the semiconductor industry and has
allowed manufacturers to continue shrinking the size of microelectronic
devices.
Since joining Vanderbilt as Stevenson Professor of Physics, Feldman
has taken on the job of directing both the Vanderbilt Institute of
Nanoscale Science and Engineering ñ the university’s interdisciplinary
research program in nanoscience and nanotechnology ñ and a national
nanoscience education program. In 2003, he received a co-appointment as
professor of materials science and engineering in the Vanderbilt School
of Engineering. He also holds positions as a distinguished visiting
scientist at Oak Ridge National Labs and adjunct professor of physics
at Fisk University. In 1999, Feldman won the David Adler Award of the
American Physical Society for his work in materials physics.
Hall was cited for "contributions to the understanding of optical
phenomena in solid-state structures, particularly those involving
waveguides." He presently serves as associate provost for research and
graduate education, professor of physics and professor of electrical
engineering at Vanderbilt. Until he came to Nashville in 2000, Hall
directed The Institute of Optics at the University of Rochester.
Throughout the 1980s and 1990s, he and his students carried out a
program of theoretical and experimental investigations of the optical
effects associated with confined systems: systems that change the way
that light travels or is emitted, absorbed or detected. The most
familiar confined system in widespread use today is the optical fiber
that confines light within a microscopically thin strand of glass.
There are a large number of possible confined systems that can be
investigated in the pursuit of deeper understanding of the nature of
light. As recorded in the pages of more than 100 research articles and
the 21 doctoral dissertations and six master’s theses that he
supervised, Hall and his students explored many such systems. As a
consequence, they discovered or demonstrated a number of subtle or
unexpected optical effects, fabricated unusual confinement structures,
and made a variety of first-ever measurements.
In 1992, Hall’s research team gained international attention for
designing and building an unusual surface-emitting semiconductor laser
based on a novel two-dimensional structure. By pushing the limits of
the technology used to create such devices, the researchers
successfully constructed a laser that forced light waves to travel as
two-dimensional circular waves, mimicking the way that water waves
travel when a stone is dropped into a pond. Another, more recent set of
experiments used a layer of light-emitting organic molecules to
demonstrate that under the right conditions, light can shine through a
layer of metal that is normally opaque.
Media contact: David F. Salisbury, (615) 343-6803
David.salisbury@vanderbilt.edu