NIST Tech Beat - April 21, 2009

Visiting aliens may be the stuff of legend, but if a scientific team working at the National Institute of Standards and Technology (NIST) is right, we may be able to find extraterrestrial life even before it leaves its home planet—by looking for left- (or right-) handed light.

The technique the team has developed* for detecting life elsewhere in the universe will not spot aliens directly. Rather, it could allow spaceborne instruments to see a telltale sign that life may have influenced a landscape: a preponderance of molecules that have a certain “chirality,” or handedness. A right-handed molecule has the same composition as its left-handed cousin, but their chemical behavior differs. Because many substances critical to life favor a particular handedness, Thom Germer and his colleagues think chirality might reveal life’s presence at great distances, and have built a device to detect it.

“You don’t want to limit yourself to looking for specific materials like oxygen that Earth creatures use, because that makes assumptions about what life is,” says Germer, a physicist at NIST. “But amino acids, sugars, DNA—each of these substances is either right- or left-handed in every living thing.”

Many molecules not associated with life exhibit handedness as well. But when organisms reproduce, their offspring possess chiral molecules that have the same handedness as those in their parents’ bodies. As life spreads, the team theorizes, the landscape will eventually have a large amount of molecules that favor one handedness.

“If the surface had just a collection of random chiral molecules, half would go left, half right,” Germer says. “But life’s self-assembly means they all would go one way. It’s hard to imagine a planet’s surface exhibiting handedness without the presence of self assembly, which is an essential component of life.”

Because chiral molecules reflect light in a way that indicates their handedness, the research team built a device to shine light on plant leaves and bacteria, and then detect the polarized reflections from the organisms’ chlorophyll from a short distance away. The device detected chirality from both sources.

The team intends to improve its detector so it can look at pond surfaces and then landscape-sized regions on Earth. Provided the team continues to get good results, Germer says, they will propose that it be built into a large telescope or mounted on a space probe.

“We need to be sure we get a signal from our own planet before we can look at others,” he says. “But what’s neat about the concept is that it is sensitive to something that comes from the process behind organic self-assembly, but not necessarily life as we know it.”

Funding for this research was provided by the Space Telescope Science Institute and the European Space Agency.

* W.B. Sparks, J. Hough, T.A. Germer, F. Chen, S. DasSarma, P. DasSarma, F.T. Robb, N. Manset, L. Kolokolova, N. Reid, F.D. Macchetto and W. Martin. Detection of circular polarization in light scattered from photosynthetic microbes. Proceedings of the National Academy of Sciences, April 20, 2009.

A research team from Northeastern University and the National Institute of Standards and Technology (NIST) has discovered, serendipitously, that a residue of a process used to build arrays of titania nanotubes—a residue that wasn’t even noticed before this—plays an important role in improving the performance of the nanotubes in solar cells that produce hydrogen gas from water. Their recently published results* indicate that by controlling the deposition of potassium on the surface of the nanotubes, engineers can achieve significant energy savings in a promising new alternate energy system.

Titania (or titanium dioxide) is a versatile chemical compound best known as a white pigment. It’s found in everything from paint to toothpastes and sunscreen lotions. Thirty-five years ago Akira Fujishima startled the electrochemical world by demonstrating that it also functioned as a photocatalyst, producing hydrogen gas from water, electricity and sunlight. In recent years, researchers have been exploring different ways to optimize the process and create a commercially viable technology that, essentially, transforms cheap sunlight into hydrogen, a pollution-free fuel that can be stored and shipped.

Increasing the available surface area is one way to boost a catalyst’s performance, so a team at Northeastern has been studying techniques to build tightly packed arrays of titania nanotubes, which have a very high surface to volume ratio. They also were interested in how best to incorporate carbon into the nanotubes, because carbon helps titania absorb light in the visible spectrum. (Pure titania absorbs in the ultraviolet region, and much of the ultraviolet is filtered by the atmosphere.)

This brought them to the NIST X-ray spectroscopy beamline at the National Synchrotron Light Source (NSLS)**. The NIST facility uses X-rays that can be precisely tuned to measure chemical bonds of specific elements, and is at least 10 times more sensitive than commonly available laboratory instruments, allowing researchers to detect elements at extremely low concentrations. While making measurements of the carbon atoms, the team noticed spectroscopic data indicating that the titania nanotubes had small amounts of potassium ions strongly bound to the surface, evidently left by the fabrication process, which used potassium salts. This was the first time the potassium has ever been observed on titania nanotubes; previous measurements were not sensitive enough to detect it.

The result was mildly interesting, but became much more so when the research team compared the performance of the potassium-bearing nanotubes to similar arrays deliberately prepared without potassium. The former required only about one-third the electrical energy to produce the same amount of hydrogen as an equivalent array of potassium-free nanotubes. “The result was so exciting,” recalls Northeastern physicist Latika Menon, “that we got sidetracked from the carbon research.” Because it has such a strong effect at nearly undetectable concentrations, Menon says, potassium probably has played an unrecognized role in many experimental water-splitting cells that use titania nanotubes, because potassium hydroxide is commonly used in the cells. By controlling it, she says, hydrogen solar cell designers could use it to optimize performance.

* C. Richter, C. Jaye, E. Panaitescu, D.A. Fischer, L.H. Lewis, R.J. Willey and L. Menon. Effect of potassium adsorption on the photochemical properties of titania nanotube arrays. J. Mater. Chem., published online as an Advanced Article, March 27, 2009. DOI: 10.1039/b822501j

** The NSLS is part of the Department of Energy’s Brookhaven National Laboratory.

Overworked crime scene investigators can take heart at the results of recent tests at the National Institute of Standards and Technology (NIST) of new technologies that automate the manual portion of latent fingerprint identification. Prototype systems evaluated by NIST performed surprisingly well for a developing technology: half of the prototypes were accurate at least 80 percent of the time and one had a near perfect score. Automating the manual portion of the work frees up time for trained examiners to spend time on very difficult images that the software has little hope of processing.

As any TV crime series fan knows, latent prints are left behind any time someone touches something. While ubiquitous, “latents” often include only part of the finger—maybe just a few ridges—and sometimes are left on textured materials, adding even more challenges.

To identify the owner, a fingerprint examiner must first carefully mark the distinguishing features of the full or partial print, beginning with the positions where ridges end or branch. Then the latent is entered into a counter-terrorist or law enforcement identification system such as the Federal Bureau of Investigation’s Integrated Automated Fingerprint Identification System (IAFIS). The FBI’s system compares latents against the 55 million sets of ten-print cards taken at arrest.

The IAFIS system was a significant advance. Now the manual, mark-up portion of latent fingerprint identification is being automated with an emerging technology called Automatic Feature Extraction and Matching (AFEM). NIST biometric researchers assessed prototypes that eight vendors are developing.

In the evaluation, researchers used a data set of 835 latent prints and 100,000 fingerprints that have been used in real case examinations.

The AFEM software extracted the distinguishing features of the latent prints, then compared them against 100,000 fingerprints. For each print the software provided a list of 50 candidates that the fingerprint specialists compared by hand. Most identities were found within the top 10.

In order of performance, the most accurate prototypes were furnished by NEC Corp., Cogent Inc., SPEX Forensics, Inc., Motorola, Inc. and L1 Identity Solutions. Results ranged from nearly 100 percent for the most accurate product to around 80 percent for the last three listed.

The evaluations also showed a strong correlation between the number of distinguishing features in a latent print and its ability to match for all prototypes and that the quality of the image data strongly influences accuracy.

“While the testing has demonstrated accuracy beyond pre-test expectations, the potential of the technology remains undefined and further testing is required,” said computer scientist Patrick Grother. “In the future we will look at lower quality latent images to understand the technology’s limitations and we will support development of a standardized feature set that extends the one currently used by examiners for searches.”

When an employee has so many complex passwords to remember that he keeps them on a sticky note attached to his computer screen, that could be a sign that your organization needs a wiser policy for passwords, one that balances risk and complexity, explains computer scientist Karen Scarfone. Scarfone is co-author of new guidelines for agency-wide password management issued for public comment by the National Institute of Standards and Technology (NIST).

Designed for federal government agencies, the new Guide to Enterprise Password Management (NIST Special Publication 800-118) can be useful to industry as well to aid in understanding common threats against character-based passwords and how to mitigate those threats within the organization. The guide covers defining and implementing password policy, educating users and measuring the effectiveness of password policies.

Passwords are a key line of defense for an organization’s data security. Passwords are used to protect data, systems and networks. Effective management reduces the risk of compromising password-based authentication mechanisms. Topics addressed in the guide include defining password policy requirements and selecting centralized and local password management solutions.

One of the document’s key purposes is to assist organizations in understanding common threats against their character-based passwords and how to mitigate those threats. Agencies need to consider using several mitigation strategies, including secure storage and transmission of passwords, user awareness activities, and secure password recovery and reset mechanisms.

The guide also is designed to raise awareness of the changing threats against passwords. Most organizations’ password policies rely primarily on password strength—an organization might require, for example, that passwords be a certain length and include a variety of letters, digits and symbols. These policies were created to protect against brute-force password guessing and cracking.

“Strong passwords don’t help as much any more because the threats have changed. Phishing attacks and other forms of social engineering trick users into revealing their passwords. Spyware in web browsers and keystroke loggers provide attackers with all the keystrokes someone makes, including passwords,” Scarfone said. Using effective password management as described in the guide will reduce the likelihood and impact of password compromises, she explained. The guide recommends that users be educated about threats against passwords and how they should respond. The publication also suggests that for some applications with high security needs, password-based authentication should be replaced with, or supplemented by, stronger forms of authentication such as biometrics or personal identity verification (PIV) cards.

The next time you shop for frozen seafood, and the price per pound seems enticingly low, make sure that you are really getting a full 16 ounces of fish. Unethical merchants or suppliers may try to have you pay fish prices for ice by including the weight of the ice, not just the weight of the fish. The National Institute of Standards and Technology (NIST) will celebrate World Metrology Day on May 20 by holding a symposium in Gaithersburg, Md. The symposium on “Measurements in Commerce: Metrology Underpinning Economic Development” will emphasize how measurement science and standards play an everyday role in our global economy.

Lisa Weddig, the director of regulatory and technical affairs at the National Fisheries Institute (NFI) in McLean, Va., will describe international trade and the importance of accurate measurements for seafood products, which represent billions of pounds of commerce every year. Fair competition between seafood suppliers only becomes possible when all sellers declare the proper weight on seafood products and avoid deceptive practices such as substituting a cheaper species of fish for the one listed on the label. NFI members have established the Better Seafood Board to ensure that fair trade exists with proper declarations on seafood products.

The United States is undergoing a subtle transition to the International System of Units (SI), commonly known as the metric system, according to NIST’s Elizabeth Gentry, who will speak on this topic at the symposium. For example, Gentry points out, food nutrition labels are expressed almost exclusively in the metric system, and consumers are gaining a feel for metric units without necessarily realizing it. U.S. corporate management is making decisions to switch immediately to SI units when the long-term and strategic benefits of international trade outweigh the costs of making a more gradual transition. As Gentry will explain, the NIST Metric Program works to facilitate the use of metric units when it is needed by industry, government and consumers.

Robert Kaarls, the Secretary of the International Committee for Weights and Measures and President of the Consultative Committee on Metrology in Chemistry, will describe how traceable measurements of chemical contaminants in international commerce can help nations better determine that the products they are importing meet their standards for safety. In addition, with nations increasing their nutritional requirements for the foods they import, traceable measurements in world trade can also better ensure that imported foods contain required levels of nutrients. The International Bureau of Weights and Measures established May 20 as World Metrology Day and encourages national measurement institutes such as NIST to celebrate metrology and its importance to society. Rich Kayser, NIST Chief Scientist, will open the NIST celebration, followed by Belinda Collins, director of NIST’s Technology Services unit, who will give an overview of the worldwide celebration of World Metrology Day.

The NIST symposium is free; members of the general public who wish to attend should contact NIST’s Sandra Auchmoody at sandra.auchmoody@nist.gov by May 15 to allow sufficient time for processing visitor registration.

Physicists have measured and controlled seemingly forbidden collisions between neutral strontium atoms, a class of antisocial atoms known as fermions which are not supposed to collide when in identical energy states. The advance makes possible a significant boost in the accuracy of atomic clocks based on hundreds or thousands of neutral atoms.

Described in the April 17 issue of the journal Science,* the research was performed at JILA, a joint institute of the National Institute of Standards and Technology (NIST) and the University of Colorado (CU) at Boulder.

The finding helps eliminate a significant drawback to clock designs based on ensembles of neutral atoms. The presence of many atoms increases both the precision and signal of a clock based on the oscillations between energy levels, or “ticks,” in those atoms. However, uncontrolled interactions between atoms can perturb their internal energy states and shift the number of clock ticks per second, reducing overall accuracy. The new techniques make JILA’s atomic clock based on strontium atoms 50 percent more accurate, so that it now would neither gain nor lose 1 second in more than 300 million years. (See “Collaboration Helps Make JILA Strontium Atomic Clock ‘Best in Class’.”)

“This is one of the most precise measurements of collisional effects in a clock,” says NIST/JILA Fellow Jun Ye, whose strontium atomic clock design enables scientists to “peek into very tiny effects.”

Fermions, according to the rules of quantum physics, cannot occupy the same energy state and location in space at the same time. Therefore, fermions, such as a collection of identical strontium atoms, are not supposed to collide. However, as Ye and his research group improved the performance of their strontium clock over the past two years, they began to observe small shifts in the frequencies of the clock ticks due to atomic collisions. They discovered that two atoms located some distance apart in the same well are subjected to slight variations in the direction of the laser pulses used to boost the atoms from one energy level to another. As a result, the atoms were excited unevenly. Strontium atoms in different internal states are no longer completely identical, and become distinguishable enough to collide. Understanding the process enabled the researchers to reduce or even eliminate the need for a significant correction in the clock output, thereby increasing accuracy.

Beyond atomic clocks, the high precision of JILA’s strontium lattice experimental setup is expected to be useful in other applications requiring exquisite control of atoms, such as quantum computing—potentially ultra-powerful computers based on quantum physics—and simulations to improve understanding of other quantum phenomena such as superconductivity.

The research described in Science was supported by NIST, the National Science Foundation, the Office of Naval Research and the Defense Advanced Research Projects Agency.

* G.K. Campbell, M.M. Boyd, J.W. Thomsen, M.J. Martin, S. Blatt, M.D. Swallows, T.L. Nicholson, T. Fortier, C.W. Oates, S.A. Diddams, N.D. Lemke, P. Naidon, P. Julienne, J. Ye and A.D. Ludlow. Probing interactions between ultracold fermions. Science. April 17.

The National Institute of Standards and Technology (NIST) has announced a three-phase plan to expedite development of key standards for a Smart Grid, a nationwide network that uses information technology to deliver electricity efficiently, reliably and securely.

Smart Grid is a key component of the Obama Administration’s commitment to moving the nation toward energy independence, and funding to spur the development process was included in the recently passed American Recovery and Reinvestment Act (ARRA). NIST is charged with coordinating the development of standards for the project.

“The Smart Grid will create jobs and contribute to the national effort to achieve energy independence and facilitate environmental improvements,” NIST Deputy Director Patrick Gallagher said. “We are working with a sense of urgency to expedite the development of standards critical to ensuring a reliable and robust Smart Grid.”

The Energy Independence and Security Act (EISA) of 2007 charges NIST with “primary responsibility to coordinate development of a framework that includes protocols and model standards for information management to achieve interoperability of smart grid devices and systems.” NIST will combine part of its own appropriation from ARRA with $10 million from the Department of Energy’s ARRA appropriation to carry out these responsibilities.

Interoperability standards are needed to ensure that software and hardware components from different vendors will work together seamlessly, while cybersecurity standards will protect the multi-system network against natural or human-caused disruptions.

By early fall, NIST expects to announce the Smart Grid architecture; priorities for interoperability and cybersecurity standards, an initial set of standards to support implementation; and plans to meet remaining standards needs.

NIST recently contracted with the Electric Power Research Institute, Inc. (EPRI) to help the agency develop an interim report on Smart Grid architecture and a standards roadmap. Headquartered in Palo Alto, Calif., EPRI is an independent, nonprofit, noncommercial organization that conducts research and development relating to the generation, delivery and use of electricity. EPRI also will support consensus-building activities to create an initial slate of Smart Grid standards.

New methods for exploring the behavior of the high-performance electronics materials and devices that will shape the future of the electronics industry will be the focus of the International Conference on Frontiers of Characterization and Metrology for Nanoelectronics, to be held the week of May 11-15, 2009, at the University at Albany.

As the electronics industry creates ever-smaller and faster chips and moves beyond silicon technology, it looks to the scientific community to provide novel measurement methods and innovative ways of using them to increase performance. Scientists and engineers from around the world will converge on the university’s College of Nanoscale Science and Engineering to discuss the challenges of exploring and characterizing these new innovations.

“The most attractive conference sessions for journalists to attend are likely the first two,” said David Seiler, chief of the Semiconductor Electronics Division at the National Institute of Standards and Technology (NIST), which is co-sponsoring the conference. The two sessions on May 12 will include keynote talks from industry leaders and an overview of nanoelectronics technology. A full conference program is available at www.eeel.nist.gov/812/conference/.

The cost for full registration, including meals, special event attendance and the hardbound conference proceedings, is $500 until the deadline of April 27, and $600 up to the conference start date.

For more information, please contact either Dave Seiler (301-975-2074) or Erik Secula (301-975-2050). Journalists interested in covering the meeting should contact Chad Boutin, boutin@nist.gov or (301) 975-4261.

Alton (Al) D. Romig, Jr., a senior executive at Sandia National Laboratories in Albuquerque, N.M., has been chosen to serve on the primary policy advisory body of the National Institute of Standards and Technology (NIST). Patrick D. Gallagher, NIST deputy director, appointed Romig to the agency’s Visiting Committee on Advanced Technology (VCAT) for a three-year term beginning on April 15.

Currently Sandia’s executive vice president, deputy laboratories director, and chief operating officer, Romig manages all aspects of the laboratory’s business and operations, which support the U.S. Departments of Energy, Defense, State, Justice, Homeland Security, the Nuclear Regulatory Commission, and the intelligence community. His activities include international engagement with organizations such as the International Atomic Energy Agency.

Trained as a materials scientist and engineer, Romig has received numerous professional awards, including the 2005 National Materials Advancement Award from the Federation of Materials Societies, which recognizes outstanding contributions to national materials policy.

The VCAT was established by Congress in 1988 to review and make recommendations on NIST’s policies, organization, budget and programs, and was recently updated by the 2007 America COMPETES Act. The next VCAT meeting will take place June 9-10, 2009, in Gaithersburg, Md.

The National Institute of Standards and Technology’s Karen Scarfone and Matthew P. Barrett received the 2009 Federal 100 Award. Presented by Federal Computer Week, the award honors the top professionals in the federal information technology community.

Scarfone, a project manager, was named for her prolific output of easy-to-understand technical security manuals that have helped numerous government organizations make their Web servers and mobile devices more secure. She has written or co-written 33 publications in the past two years, mainly covering incident response, host security and telework security. In 2008 there were 4 million Web page requests for her publications. Scarfone also used her technical expertise to help update the widely used Common Vulnerability Scoring System that measures vulnerabilities.

Barrett was acknowledged for leading the team that provides several computer security programs for federal agencies including the Security Content Automation Protocol (SCAP), the National Vulnerability Database, the National Checklist Programs and the SCAP Laboratory Accreditation program. As a representative to the Office of Management and Budget’s working group for the Federal Desktop Core Configuration, he coordinated efforts by OMB, other agencies and Microsoft to develop a secure configuration for government PCs. Working with the Information Security Automation Program working group, Barrett worked with counterparts at the National Security Agency and the Defense Information Systems Agency to coordinate the interagency security automation agenda.

Ron Ross, senior computer scientist and information security researcher at the National Institute of Standards and Technology (NIST) has been named to the Information Systems Security Association’s (ISSA) Hall of Fame for his leadership in the development of influential information security documents. This honor is the association’s highest tribute.

Ross manages the Federal Information Security Management Act (FISMA) Implementation Project that has driven the federal government and many commercial organizations to focus on information security from a risk-based perspective. He was the principal architect of the NIST Risk Management Framework that integrated the suite of FISMA security standards and guidelines into a comprehensive enterprise-wide information security program.

While assigned to the National Security Agency, he received the Scientific Achievement Award for his work on an inter-agency national security project and was awarded the Defense Superior Service Medal upon his departure from the agency. He is a two-time recipient of Federal Computer Week’s Federal 100 award.

ISSA is an international association of information security practitioners that work to protect privacy, data and systems for businesses, government, education, healthcare and law enforcement.

(Return to NIST News Page)

Editor: Michael Baum

Date created: April 21, 2009
Date updated: April 23, 2009
Contact: inquiries@nist.gov