“DNA Chip”: Potential Catalyst for Probing DNA to Detect and Repair Genetic Damage
Jacqueline K. Barton, Ph.D., professor of chemistry and chair of the division of chemistry and chemical engineering at the California Institute of Technology, has been working toward deepening the fundamental understanding of charge transport through DNA.[(DNA, or deoxyribonucleic acid, is the hereditary material in humans and almost all other organisms. Nearly every cell in a person’s body has the same DNA. Most DNA is located in the cell nucleus (where it is called nuclear DNA), but a small amount of DNA can also be found in the mitochondria (where it is called mitochondrial DNA or mtDNA)]. http://ghr.nlm.nih.gov/handbook/basics/dna
For her work and discoveries, Barton was awarded the 2015 Priestley Medal by the American Chemical Society (ACS). Her efforts have led to the development of a “DNA chip” that could potentially probe strands of a person’s genetic material, explains the ACS. Harry Gray, Ph.D., who nominated Barton for the award, says “Barton’s results have spawned both theoretical and experimental studies across the world to examine the conductivity of DNA.”
Barton received the 2010 U.S. National Medal of Science, the nation’s highest honor for scientific achievement, for discovering that cells use the double strands of the DNA helix like a wire for signaling, which is critical to detecting and repairing genetic damage, the ACS explains. The annual award includes a gold medallion designed to commemorate the work of Joseph Priestley, who lived from 1733 to 1804. In 1774, he discovered the gas that was later identified as “oxygen.” (ACS press release, June 11, 2014) http://bit.ly/1vGKfNp
Hydrogen Storage: One Proposed Solution
Among the issues that scientists have been working to resolve in connection with replacing fossil fuels with the clean fuel hydrogen is how to store hydrogen safely and efficiently. Umit B. Demirci, Ph.D., of the Institut Européen des Membranes, Université Montpellier 2, and colleagues explain in “Lithium Hydrazinidoborane: A Polymorphic Material with Potential for Chemical Hydrogen Storage,” published in the ACS journal Chemistry of Materials, that a new solid, stable material can pack in a large amount of hydrogen and be used to store hydrogen.
The Demirci team developed a crystal phase of a material containing lithium, boron, and hydrogen. They then heated the material to see if the hydrogen would be released from it. The hydrogen released easily and quickly, and with only traces of unwanted by-products, according to the American Chemical Society.
Locator for Urban Search and Rescue Operations
The June feature of Science Elements, the American Chemical Society’s (ACS’) weekly podcast series (June 5, 2014), highlighted devices that use chemistry to locate people trapped in collapsed buildings. In the episode, Milt Statheropoulos, Ph.D., discussed work that he and colleagues across Europe have been doing on a project called “Second Generation Locator for Urban Search and Rescue Operations.” It includes an automated network of chemical sensors, as well as a portable device that rescuers can take into the field with them. Most recently, they developed a vapor, or scent, generator that workers can use to train rescue dogs. The episode is available at www.acs.org/scienceelements.
Author’s Note: The American Chemical Society is a nonprofit organization chartered by the U.S. Congress. It is the world’s largest scientific society and a global leader in providing access to chemistry-related research through its multiple databases, peer-reviewed journals and scientific conferences. Its main offices are in Washington, D.C., and Columbus, Ohio. General inquiries may be referred to Michael Bernstein at [email protected], 202-872-6042; science inquiries may be sent to Katie Cottingham, Ph.D., [email protected], 301-775-8455.
DARPA Technology: Scaling Vertical Walls and Air Support Adapted for Wildland Firefighting
The Defense Advanced Research Projects Agency (DARPA) is an agency of the United States Department of Defense responsible for developing new technologies for use by the military. Here, we will look at two technologies. One has already been adaped for use in the fire service; the other may have potential application for the fire service. The fire service has been the beneficiary of numerous technologies that originally were developed for the miliary.
The Z-Man Program
It features paddles that employ polymer microstructure that makes it possible for a human to climb a glass wall. The paddles, developed for DARPA by Draper Laboratory of Cambridge, Massachusetts, were designed to facilitate warfighters’ scaling vertical walls constructed from typical building materials while carrying a full combat load. The paddles were modeled after the toe of a gecko, a superior climber. In the first human test of the paddles, a 218-pound climber, carrying a 50-pound load, ascended and descended 25 feet of glass using no climbing equipment (such as ladders and ropes) other than a pair of the hand-held paddles. The anatomy of a gecko’s toe consists of a microscopic hierarchical structure composed of stalk-like setae (100 microns in length, 2 microns in radius). From individual setae, a bundle of hundreds of terminal tips called spatulae (approximately 200 nanometers in diameter at their widest) branch out and contact the climbing surface.
Dr. Matt Goodman, the DARPA program manager for Z-Man, noted: “The challenge to our performer team was to understand the biology and physics in play when geckos climb and then reverse-engineer those dynamics into an artificial system for use by humans.”
Engineers had to create climbing paddles that were able to balance sufficient adhesive forces in both the shear (parallel to the vertical surface) and normal (perpendicular to the vertical surface) directions so that a climber can remain adhered on a surface without falling off while he attached and detached the paddles with each movement. The first human climb took place in 2012; tests have been ongoing. Information on the Z-Man Program is available at http://bit.ly/1ofka8c.
During testing, an operator climbed 25 feet vertically on a glass surface using no climbing equipment other than a pair of hand-held, gecko -inspired paddles. The climber wore, but did not require, a safety belay. Photo: Courtesy of DARPA
The FLASH Program
Fire Line Advanced Situational Awareness for Handhelds (FLASH) is a prototype technology system designed to improve firefighter effectiveness and safety by providing real-time situational awareness to every firefighter and firefighting aircraft in expansive fire zones. Adapted from DARPA’s Persistent Close Air Support (PCAS) technology, FLASH overlays multiple streams of information from airborne sensors, firefighters and fire command posts onto a shared digital map visible via tablet computers. (Image: Courtesy of DARPA.)
The Persistent Close Air Support (PCAS) program, developed to provide warfighters with advanced digital tools for situational awareness and targeting in place of legacy communications systems and traditional paper maps, was the source of this technology that will now be made available to firefighters battling wildfires through the Fire Line Advanced Situational Awareness for Handhelds (FLASH) program. On May 27, DARPA personnel traveled to Prescott, Arizona, to collaborate with the fire department in the testing of the technology. The prototype system included tablet computers, aircraft-mounted sensors, and radios designed to identify the location of every firefighter and firefighting aircraft in expansive fire zones. The system overlays multiple streams of information from airborne sensors, firefighters, and fire command posts onto a shared digital map visible on tablet computers.
During the three-day training demonstration, the firefighters were able to track each other’s positions in real time, monitor the position of an observation aircraft overhead, and watch a live-video feed from the aircraft that provided a bird’s-eye view of the terrain. Participants in a command post in Prescott and observers at DARPA’s offices in Arlington, Virginia, viewed the same live video feeds from the aircraft and communicate in real time with firefighters in the field. The FLASH system relies in part on Mobile Ad Hoc Networking (MANET) radio technology. “This training demonstrated the potential of MANETs and tactical tablet computing to provide powerful, flexible shared situational awareness for the fire community,” said Dan Patt, DARPA program manager. “We’re leveraging ongoing DARPA investments initially aimed at warfighters to help firefighters coordinate their efforts in ways we believe can increase firefighting effectiveness, as well as firefighter safety.”
The demonstration took place near the area where 19 firefighters from the Prescott Fire Department’s Granite Mountain Hot Shots unit gave their lives on June 30, 2013, battling the Yarnell Hill wildfire. “We chose Prescott for the demo to honor the memory of the firefighters who gave their lives serving others,” said Chuck Wolf, deputy director of DARPA’s Adaptive Execution Office, which helped modify PCAS technology to fight wildfires. “We want to get this technology into the hands of firefighters already battling wildfires this year, to hopefully prevent a tragedy like Yarnell Hill from ever happening again.”
Exercise participants were quite impressed with the FLASH prototype’s capabilities. “This technology has great potential to increase situational awareness as well as personnel accountability, two things paramount to a successful and safe wildfire operation,” said Kevin Keith, fire captain in the Prescott Fire Department. Mike Worrell, fire captain in the Phoenix (AZ) Fire Department and member of the Federal Emergency Management Agency’s Incident Support Team/Arizona Task Force-1, who also attended the training, noted: “FLASH could have a big impact on fireground safety and efficiency. The ability for incident commanders to have voice communications, monitor position and mission progress, and exchange data in real time has been nonexistent. For the first time, we were able to do wide-area searches and send search data immediately instead of taking hours to collect and process data from the field before returning it to the people who need it.”
FLASH could help address smaller-scale incidents as well, such as search and rescue in difficult terrain. A separate but related demonstration included a live simulation of finding and retrieving an injured hiker in the nearby mountains. Triangulating from the person’s 911 call, the FLASH-equipped team found the person within 15 minutes—a task that currently can take hours or even days.
The Prescott Fire Department plans to continue testing the FLASH prototype systems. DARPA is producing training materials on how to use the equipment so additional firefighters can continue evaluating its usefulness. Information on the FLASH program is at http://bit.ly/1hKpH3T.
“I can only imagine the usefulness of equipment like this, from simple emergencies all the way to large-scale wildfires and other all-risk incidents,” said Ralph Lucas III, battalion chief for the Prescott(AZ) Fire/Medical Department, whose team participated in the rescue demonstration. (Image: Courtesy of DARPA.)
MARY JANE DITTMAR is senior associate editor of Fire Engineering and conference manager of FDIC. Before joining the magazine in January 1991, she served as editor of a trade magazine in the health/nutrition market and held various positions in the educational and medical advertising fields. She has a bachelorâs degree in English/journalism and a masterâs degree in communication arts.