Discover Magazine honored the Department of Energy's Pacific Northwest National Laboratory for two of its new technologies -- a landmine detector and a combined optical and magnetic resonance microscope for cellular research
Robert Wind and his combined optical and magnetic resonance microscope
June 12—Discover Magazine and the Christopher Columbus Foundation recognized scientists at the Department of Energy's Pacific Northwest National Laboratory in a ceremony today for developing two innovative technologies that will address vital health and humanitarian issues.
PNNL scientists won two of the nine 2001 Discover Magazine Innovation Awards given this year. From the basic science side of the laboratory, physicist Robert Wind accepted the top honor in Discover's Health category for inventing a combined optical and magnetic resonance microscope that has potential for improving the detection and diagnosis of diseased cells and in evaluating a patient's response to therapy.
Also, as part of the awards program, the Christopher Columbus Foundation granted PNNL physicist Richard A. Craig a $100,000 fellowship for development of the Timed Neutron Detector, which quickly and inexpensively locates metal and plastic landmines.
Congress established the Christopher Columbus Foundation in 1992 to "encourage and support research, study and labor designed to produce new discoveries in all fields of endeavor for the benefit of mankind." It chooses a fellowship recipient each year from among entries to the Discover Awards.
"Using different approaches, both of these scientists have pursued the common
goal of putting science and technology to work for the benefit of society,"
said Secretary of Energy Spencer Abraham. "Their research ranges from a tiny component of every human being—the cell—to an international issue that impacts millions of global citizens—the proliferation of landmines. We're proud of their groundbreaking work."
Combined Optical and Magnetic Resonance Microscope
This new microscope merges magnetic resonance and optical microscopy in a powerful system to study cellular activity, such as cancer development or tumor death. Magnetic resonance microscopy uses the same methods as magnetic resonance imaging, or MRI, a technique used commonly in hospitals.
"This unique combination provides scientists with more information about cells than either technique offers individually," said Wind. "Because of this new approach, we'll have a more accurate and complete picture of cellular activity, particularly events related to the development of cancer and other diseases and the cellular response to therapy. We're seeing details of the cell and its activity that haven't been viewed before."
Current approaches for studying cellular events include breaking up dead cells, which usually results in the loss of valuable information. In contrast, the combined microscope allows scientists to study live cells and how they respond to stresses over time simultaneously with two completely different microscopic techniques. The combined microscope takes advantage of optical microscopy's extremely high-resolution images and MRI's ability to capture physical and chemical information of cells, such as water properties and the presence of certain chemical compounds. Just as the microscopes are combined, the data obtained by each is integrated to provide a more complete examination of the cell.
Wind's team began its studies with the combined microscope using a frog cell. These cells are commonly used because of their large size. Successful results from those studies, including the first combined images ever taken of a live frog cell, led to funding from the National Cancer Institute to analyze programmed cell death, or apoptosis, in mammalian cells.
The combined microscope will allow scientists to obtain more accurate "signatures" of cell death. These signatures are telltale signs that diseased cells have died as a result of chemotherapy. In initial studies, cell death was monitored in hamster ovary cells as they were deprived of energy and noted that a cell's volume, water mobility and metabolism changed. These studies suggest that these properties may be good indicators, or signatures, of cell death.
Currently, doctors can't gauge chemotherapy's effectiveness until they see tumors regress. PNNL researchers hope the cellular information obtained by the combined microscope will help doctors learn early on if chemotherapy treatment is working.
The Timed Neutron Detector
Contrast is the key to all systems designed to locate landmines. The Timed Neutron Detector focuses on the contrast between hydrogen in the ground and in landmines. It recognizes the presence of hydrogen in the casings and explosive materials of plastic or metal landmines.
While other landmine detection systems also can locate plastic and metal mines, the Timed Neutron Detector goes a step beyond. It is portable, comparatively inexpensive and easy to operate.
"We wanted to develop a system that would be feasible for use in countries that have the greatest need for this capability," said Craig, a physicist and principal investigator. "Simplicity has been our goal since the beginning, and our system is elegantly simple."
Gruesome images of landmine victims motivated Craig and the team with which he worked. Each year, landmines claim 24,000 new victims, of which nearly 10,000 die (according to the Landmine Survivors' Network). The United Nations' Landmine Database estimates that at present rates it would take 1,100 years to clear the world's 110 million landmines hidden in the soils of nearly 70 countries.
Rosalyn Queen Alonso, Christopher Columbus Foundation chair, commended Craig's team for this development. "This device can be produced for use by Third World countries at a relatively low cost, yet the savings in human life and suffering could be priceless," she said. "If landmines are neutralized, these countries and their people could begin to rebuild their lives and restore their agriculture."
With the goal of practicality, the team developed a system that would detect hydrogen because it is a common element of all landmines. Hydrogen exists in the explosive material of metal landmines as well as the casings of plastic mines.
The Timed Neutron Detector resembles a metal detector, but unseen neutrons from Californium-252 shoot out of the detector into the soil. As neutrons leave the detector, a time-tagging radiation source (obtained from DOE's Oak Ridge National Laboratory) records each neutron's exit and return.
Then, neutrons return after either interacting with the soil or with hydrogen found in landmines. Neutrons that interact with soil will return to the detector at nearly the same speed at which they left. The detector ignores those neutrons and focuses instead on the neutrons that interact with hydrogen. The neutron's speed slows down when it interacts with hydrogen because it has about the same mass as a hydrogen nucleus.
"It's like playing billiards in a way," Craig said. "When a cue ball strikes another ball of the same mass, the second ball will 'take' part of that energy and move. So the cue ball loses energy and slows down. In the same way, neutrons that collide with hydrogen will slow down because they are about the same mass. We simply detect those slowed neutrons."
Craig and his team plan to use the foundation's award to further refine the Timed Neutron Detector. They expect to test it at a mock landmine field later this year.
This is the 12th year the magazine has recognized top technological innovations in science and technology. Both PNNL winners will be featured in Discover's July 2001 issue. You can also visit Discover Magazine online at http://www.discover.com.—by Staci Maloof
The Department of Energy's Office of Science is the single largest supporter of basic research in the physical sciences in the United States and is working to address some of the most pressing challenges of our time.