This issue...
News in Brief
View from the Inside
Lyme Disease
A Lucky Catch
Artificial Pancreas
People
About
Subscribe Free
This issue...
News in Brief
View from the Inside
Lyme Disease
A Lucky Catch
Artificial Pancreas
People
About
Subscribe Free
|
News in Brief
2001 Discover Magazine Innovation Awards
Discover Magazine honored the Department of Energy's Pacific Northwest National Laboratory (PNNL) for two of its new technologiesa landmine detector and a combined optical and magnetic resonance microscope for cellular research. The awards were presented on June 12 during a ceremony at the Manhattan Center in New York City.
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.
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.
Full article and related web links available on the Office of Science website, and the Discover Magazine.
Media contact: Staci Maloof, PNNL, (509) 372-6313, Staci.Maloof@pnl.gov
Research contacts: Richard Craig, Timed Neutron Detector, (509) 372-2449, r.a.craig@pnl.gov
.
Robert Wind, combined optical and magnetic resonance microscope, (509) 376-1115, Robert.Wind@pnl.gov.
|
Information Overload Distracts Drivers
Car drivers are heading down that path of information overload, and researchers at the Department of Energy's Oak Ridge National Laboratory are looking for ways to prevent it.
"People are taking their cell phones, CDs, and computers with them in their cars," says Phil Spelt, principal investigator at ORNL's In-Vehicle Information System (IVIS) Development Center. He points out that, at the same time, newer cars have built-in systems that warn of potential collisions, display street signs, inform drivers about the condition of their cars, and give navigation directions.
Currently, there is no method for "managing" the information a driver receivesit all has equal priority. It is completely plausible that a driver would receive a phone call, a collision alert, a low-fuel warning, an instruction to turn right, and an internet stock update at the same time. How do drivers react?
According to recent studies, not particularly well. Spelt studied 36 men and women as they "drove" in a simulator while being rapidly bombarded with information from a cell phone, a collision-warning device, a navigation system, and an Internet-equipped computer screen. There were a few crashes; one out of six of the drivers missed a turn during one of their 10-turn experimental runs; the majority could not remember much of the unmanaged general information (for example, the answers to simple addition problems) they had received.
Spelt and his colleague, Daniel Tufano, are working on an in-vehicle information system (IVIS) that will manage competing bits of information being directed at drivers. A IVIS would, for example, filter phone calls, checking them against a database and passing them on to the driver only if they were relevantfor instance, if they came from a known source. Information such as navigational cues would have precedence over phone calls, and the driver would receive prompts on where to go before being alerted to the phone call. Safety warnings, such as collision alerts, would have the highest priority.
IVIS is a component of the Department of Transportation's Advanced Traveler Information System, which is working on methods of delivering a wide range of information to drivers while they are inside their cars. The project has the support of General Motors Corp. and Ford, who have each invested $10 million in their own investigations.
"The motor companies see this as a potential new market and a set of capabilities customers will demand," observes Spelt, "but they are also keenly aware of the liability issues."
Full article and related web links available on the Office of Science website.
Research contact: Phil Spelt, ORNL, (865) 574-7472, speltpf@ornl.gov
|
Strengthening the Public Information Infrastructure for Science
Workshop Summary: A workshop was convened April 18-19, 2001, for Federal agencies, academic experts, and other information professionals to explore the means for improving access to the science information of the Federal agencies. Over 60 participants from 33 different organizations participated in the Workshop, which was sponsored by the DOE and organized by the CENDI Information Managers Group, the University of Maryland Center for Information Policy, the DOE Office of Science's Office of Scientific and Technical Information (OSTI), the National Institute of Standards and Technology, and the National Science Foundation.
This workshop, along with the DOE-sponsored May 2000 workshop which resulted in the Trivelpiece Report on a "Future Information Infrastructure for the Physical Sciences" (available at http://www.osti.gov/physicalsciences), gave participants the opportunity to review recent developments in the changing context for science information. Developments include the National Science, Mathematics, Engineering, and Technology Education (SMETE) Digital Library (NSDL) Program at the National Science Foundation, the organization of private-sector resources around SMETE.ORG, the new Administration's policies on e-government, the success of FirstGov, the growth of open archives within the academic research community, and the emergence of technologies for improving access to materials on the Web.
Participants endorsed the concept of an initiative for an interagency science portal whereby the agencies would collectively serve the science-attentive citizen. The interagency science portal was also described as a unified navigation path to science done by the government. The agency representatives agreed to seize the opportunity and formed a "Science.gov Alliance" to work on the interagency effort. The Alliance, composed of CENDI plus other representatives, will plan the collaborative science initiative. A Core Team of the Science.gov Alliance met on May 18, 2001, and DOE was represented by Dr. Walter L. Warnick, Director, Office of Scientific and Technical Information.
Contact: Walter L. Warnick, OSTI, (301) 903-7996, walter.warnick@science.doe.gov
|
New Cancer Biosensor
Scientists at the Department of Energy's Ames Laboratory have developed a chip-based, direct-readout methodology for detecting and quantifying DNA adducts, chemical compounds in which a carcinogen is attached to the DNA.
This newly developed biosensor chip tool, which scientists hope will aid pre-cancer diagnoses, consists of a gold biosensor chip with specific antibodies that can selectively bind carcinogen-derived (depurinating) DNA adducts excreted into urine. The DNA adducts are identified through high-resolution, "fingerprint" spectra that, in some cases, could be used in assessing and tracking a patient's risk of getting cancer.
Early detection for many types of cancer (lung, breast, prostate, etc.) in asymptomatic patients significantly improves survival chances, according to the American Cancer Society.
Until now, methods for early detection have relied either on the patient or doctor to find an indication of cancer in time, or on instruments that don't always detect miniscule changes in cells. Even patients known to have been exposed to carcinogens may not show any signs of cancer until it's too late.
While still in the development stage, the new biosensor is part of ongoing studies at Ames Lab to address the effects of cancer-causing agents on cellular DNA and is related to another technology, Capillary Electrophoresis Fluorescence-Line Narrowing Spectroscopy (CE-FLNS), which won an R&D 100 award from Research and Development Magazine as one of 100 significant new technologies in 1998.
The CE-FLNS system makes identifying and characterizing trace amounts of modified DNA much more definitive than using analytical methods separately. Through CE, sub-nanomolar amounts of closely related biological compounds are separated, and low-temperature, high-resolution spectroscopy further distinguishes structurally similar molecular compounds based on laser-excited FLN spectra, which can be collected in on-line analysis. A similar technique substitutes high performance liquid chromatography for the CE, with equally successful results.
The main drawback to these systems is that they are time consuming and would be too expensive for general use, for example, in routine assessments of workers regularly exposed to carcinogens such as polycyclic aromatic hydrocarbons from industrial processes.
That's where the new biosensor comes in. The chips can selectively bind adducts of interest, which can be detected and identified by FLNS (4.2 K, or minus 452ºF), and/or by non-line-narrowed (NLN) fluorescence and/or phosphorescence spectroscopy at 77 K (minus 321ºF).
The illustration on the right is a calculated structure of a DNA adduct-formed when cancer-causing chemicals metabolize and bind with DNA bases. Certain unstable adducts (depurinating) eventually migrate to body fluids, like urine. The biosensor chip being developed at Ames Laboratory detects and identifies these adducts in urine samples, and shows potential as a new way to provide information for cancer risk assessment.
Ryszard Jankowiak, head of the biosensor chip research project, said, "We are trying to develop sensitive and selective techniques for carcinogenesis, with the scope of determining potential biomarkers for susceptibility to cancer. Currently, we are concentrating on biomarkers implicated in breast and prostate cancers, which, based on our preliminary data, could be identified at 77 K by NLN spectroscopy. This would lead to lower detection limits and a more cost-effective approach."
Full article and related web links available on the Office of Science website.
Media contact: Saren Johnston, Ames Laboratory, (515) 294-3474, sarenj@ameslab.gov
Research contacts: Ryszard Jankowiak, Ames Laboratory, Chemical and Biological Sciences, (515) 294-4394, jankowiak@ameslab.gov
Gerald Small, Ames Laboratory, Chemical and Biological Sciences, (515) 294-3859, gsmall@ameslab.gov
.
|
Building a Better Baby Diaper
The Department of Energy's Advanced Light Source at Lawrence Berkeley National Laboratory gave DOW Chemical Company an x-ray spectromicroscopic look at the crosslinking of its superabsorbent polymer gel, and helped them to improve the manufacturing process.
Baby diaper manufacturers face a two-fold challengeto keep the baby dry, the diaper must be able to take up a large quantity of liquid, and then, as baby diaper scientists describe it, the diaper must "hold it under load" as the baby moves around.
Superabsorbent polymer materials with long chains of intertwining molecules are able to soak up lots of liquid. By means of chemical reactions on the surfaces of submillimeter-sized superabsorbent polymer beads, manufacturers fashion thin shells of tightly "crosslinked" polymer in which the strands are connected at the cross links. The shell makes it more difficult for liquid to leak out, but actual performance depends on the microscopic details of the shell structure, such as variations in the crosslinking through and around the shell.
To obtain the desired information, the researchers turned to near-edge x-ray absorption fine structure (NEXAFS) spectromicroscopy, using a scanning transmission x-ray microscope at the Advanced Light Source. They were able to make images of the polymers in the fully hydrated state (in excess water). Because the x-ray energy could be tuned to a value where the carbon in the polymer absorbs and the water is almost transparent, they could map the areas where crosslinking was higher by observing the increased carbon content in these regions.
 | NEXAFS spectromicroscopy images of shells formed around SAP beads by two different methods. (A) Images of a bead crosslinked with ethylene glycol diglycidyl ether at three photon energies. The shell is the arc of graded density with the outer surface to the right. (B) Map of the polymer concentration obtained from analysis of the three images. (C) Similar polymer concentration map for a bead crosslinked with glycerol showing a sharply delineated density profile. |
Crosslinking was stimulated by treating the surface of the superabsorbent polymer beads with varying solutions. Sectioned beads were then exposed to a saline solution to put them in the fully swollen state for imaging. Analysis of the images yielded two extreme cases for the crosslink profile through the shell. In one, the crosslink density decreased smoothly over a distance of 18 microns from a maximum at the outer surface. In the other, the density was uniform over a distance of five microns and then dropped abruptly.
These differences reflect a complicated interplay between the dynamics of the swelling of the bead in water, the diffusion rate of the crosslinker in the water phase, and the rate of the crosslinking reaction. And, this interplay can make or break a better baby diaper.
Full article with related web links available on the Office of Science website.
Media contact: Art Robinson, ALS, ALRobinson@lbl.gov
, (510)486-6838
Research contacts: G.E. Mitchell, Dow Chemical Company, gemitchell@dow.com
H.W. Ade, North Carolina State University, harald_ade@ncsu.edu
|
|
|