Duke researchers create polymer coating to keep bacteria, barnacles at bay
Published in the April 15, 2013, Raleigh News & Observer and the April 14, 2013, Charlotte Observer
By Whitney L.J. Howell
Swatting at pesky insects or air-borne particles – it’s a common, everyday activity for nearly all living creatures. It’s a way to keep clean and get rid of anything that might cause future problems.
But what about machines and vehicles that can’t take a swing at annoying parasites, particularly ones submerged in water?
Continual biofouling – the accumulation of microorganisms, plants, algae, or animals on wet surfaces – has been a long-term problem for the global shipping industry. Now researchers at Duke University’s Pratt School of Engineering have developed a strategy that could enable ships to rid themselves of creatures and substances that hitch a ride on their hulls.
Coating ships in a new material that shakes itself on command can eliminate several problems associated with keeping ships clean, said Xuanhe Zhao, a Duke mechanical engineering researcher.
“If you’ve ever seen a horse or cow shake its skin or tail to get rid of flies, that’s analogous to shaking off something that’s bugging the ship,” he said. “We’ve introduced a new mechanism that can deform, and that deformation can literally detach the biofouling materials adhering to the surface.”
Why slough the ships?
Apart from being unsightly, barnacles and other biofouling substances can inhibit a ship’s ability to function. Even a small amount can cause difficulties, said Gabriel López, a Duke biomedical and mechanical engineering professor. He is also the director of Research Triangle Materials Research Science and Engineering Center.
“Even a small layer of slime can significantly increase drag, and
This extremely enlarged image shows a covering of green microorganisms being lifted off the metal to which it is attached. The metal was coated with a polymer developed at Duke University’s Pratt School of Engineering. When an electric current goes through the polymer, the coating becomes bumpy, forming patterns that can detach the biofouling.
COURTESY OF XUANHE ZHAO
as drag on the ship goes up, the fuel consumption goes up, as well,” he said. “Pollution goes up, and more greenhouse gases are produced.”
Leaving biofouling materials stuck to ships can also have another environmental impact. For ships sailing worldwide, there is a risk invasive species will be transferred from their native habitat to ones where they can be damaging. For example, nutrient-hoarding zebra mussels from Russia were brought via ship hull to the Great Lakes in the late 1990s. Within 10 years, these invaders had wreaked havoc on the region’s fishing industry and levied more than $3 billion in damages.
Ridding ships of biofouling materials is also of military import, López said. The more barnacles and bacteria a ship carries, the noisier the vessel is, making it easier to detect.
How it works
Traditionally, the shipping industry used less-than-optimal means to protect vessels. For more than 40 years, global maritime companies coated their roughly 30,000 ships with paint containing tributyltin, an inexpensive, effective – and poisonous – barnacle- and algae-killer. An international treaty banned its use in 2007.
Another protection method has been a polymer coating that reduces biofouling substances’ ability to adhere to the boat. It’s a temporary fix, though, because bacteria and barnacles eventually adapt to the polymer and attach themselves anyway, Zhao said.
This new solution, however, starts with an environmentally safe silicon rubber polymer coating on the ship’s hull. Running voltage through the flat polymer turns it into a capacitor – a passive structure that stores energy – and generates an electric field, he said. This cleaning strategy then relies on electrostriction, a property of electrical nonconductors that allows them to change shape when exposed to electricity, to slough away the offending substances.
“There are patterned channels – air channels – beneath the polymer, and if you blow air into the channels, it will increase the hydrostatic pressure and buckle up the polymer surface,” Zhao said. “We basically form a wrinkle on the surface of the polymer, and the biofouling substances simply detach.”
Although this strategy must be tested on the large scale, it does offer two advantages other cleaning solutions have lacked, Zhao said. The silicon rubber polymer could potentially last for years, and this method eliminates the need to dry dock a ship for cleaning. An electric current can be sent to the polymer anytime, anywhere, and the ship will slough off biofouling material.
Challenges, future uses
To date, Zhao and López have only tested this self-sloughing mechanism with areas only a few centimeters wide. But, according to Jan Genzer, a chemical and biomolecular engineer at North Carolina State, larger experiments are needed to prove it’s a valid cleaning solution.
“It’s a very clever, very different way to think about this problem – like trying to stand on a trampoline while it’s being shaken,” said Genzer, who created a different cleaning solution. “The real question is, though, can it be applied to a ship? How will the research translate to application? Will the discovery need to be modified?”
In his discovery, Genzer and his colleagues created a dense layer of molecules capable of repelling biofouling organisms by repeatedly hitting a stretched piece of rubber with reactive oxygen and allowing the rubber to rebound. The result, he said, was a roughness that helped prevent barnacle and algae accumulation.
Even though the self-sloughing mechanism has only been applied to shipping so far, both Zhao and Genzer agree that there are additional uses for this technology. Representatives from the food industry, lubrication companies, and medical device manufacturers have all expressed interest in this development, Zhao said.
“Any time you have synthetic material in contact with some sort of water that might have bacteria or other microorganisms in it, you will form this biofouling layer,” he said. “So, it’s a very pervasive problem.”
Ultimately, Genzer said, concentrating on strategies to remove biofouling materials rather than trying to create ones that prevent accumulation from even beginning will be a productive plan. Organisms adapt to survive when faced with foul-resistant substance, and that can do more harm than good to an ecosystem.
“People are now realizing foul-resistant coatings are more realistic. They allow deposits to settle, but they can be cleaned by shaking or running the ship at particular speeds,” Genzer said. “You can’t outsmart Mother Nature. She’s been around for millions of years, and she’s developed ways for organisms to survive in different conditions. If we can get surfaces clean, we should be happy, and leave it at that.”
Can solar power be made cost-efficient?
Published in the Nov. 28, 2011, Raleigh News & Observer and Charlotte Observer
By Whitney L.J. Howell
Solar power has always been considered an environmentally friendly energy source. Duke University research could make the strategy not only green but also cost-efficient.
Atop Duke’s Pratt School of Engineering, assistant professor Nico Hotz is constructing a test-model hybrid solar cell to capture sunlight and use it to heat a water-methanol combination. The system creates hydrogen that can be stored and used to power fuel cells later.
Duke University's Nico Hotz is testing a hybrid solar cell. Courtesy: Duke University Pratt School of Engineering
“With a hybrid system in the summer, we can turn 28.5 percent of the energy produced into something else – that’s 10 percent more than with a conventional system,” Hotz said.
He’s testing whether his system can work at a large scale.
“In the winter, the increase is the same: 15 percent versus 5 percent. It’s a more efficient system.”
Hotz compared the hybrid to three existing systems: one that directly converts sunlight to electricity and splits water into hydrogen and oxygen, one that stores converted sunlight in different types of batteries, and one that is simpler, though similar, to Hotz’s. The hybrid is the least expensive, he said, with installation costs totaling $7,900. Conventional installations can cost as much as $40,000.
The hybrid mimics conventional solar cells by collecting sunlight. It is different, however, because it runs a water-methanol mixture through vacuum-sealed copper tubes coated with aluminum and aluminum oxide. This structure allows the water to heat up to at least 200 degrees Celsius (392 Fahrenheit). The heat is necessary to produce hydrogen. Hotz said standard solar cells reach only 60 to 70 degrees Celsius (140-158 Fahrenheit).
At the appropriate temperature, Hotz’s team infuses small amounts of catalyst to kick off hydrogen production.
“This reaction produces hydrogen efficiently,” Hotz said. “It can be used immediately or stored in a tank to be used later, perhaps by homeowners who want it in the winter months to supplement their other energy sources.”
However, according to Clemson University engineering professor Rajendra Singh, a commercial application of Hotz’s research is unlikely.
“This is great basic research, but it won’t change the world.” Singh said. “There’s not a single system in existence that can economically produce hydrogen.”
To read the story on the Raleigh News & Observer site: http://www.newsobserver.com/2011/11/28/1675178/can-solar-power-be-made-cost-efficient.html
To read the story on the Charlotte Observer site: http://www.charlotteobserver.com/2011/11/28/2809554/can-solar-power-be-cost-efficient.html#storylink=misearch
Duke’s virtual reality chamber help with teaching, research
Published in the Dec. 13, 2010, Raleigh News & Observer and the Dec. 13, 2010, Charlotte Observer
BY WHITNEY L.J. HOWELL – CORRESPONDENT
DURHAM — At first, the walls of the six-sided room are covered with a dull plaid test pattern.
But press a button, and a giant 3-D brain suddenly appears in mid-air. Click a few more keys, and an entire city stretches ahead – just like in a “Star Trek” holodeck.
The room is a sci-fi fantasy for real. It’s the Duke immersive Visual Environment, a six-sided structure that, when sealed, becomes a seamless virtual reality atmosphere built to enhance teaching, research and design planning.
Housed at the Pratt School of Engineering, DiVE is the only room of its kind on the East Coast. Only three other American universities – the University of Illinois at Chicago, the University of Illinois at Urbana-Champaign and the University of Iowa – have six-sided rooms. Several other research groups have three-sided or four-sided chambers.
“There are many activities that should be done in immersive environments,” said Rachael Brady, director of DiVE and Duke’s visualization technology group. “The technology helps people visualize and better understand theirdata.”
For example, a Duke medical student studying to be an orthopedic surgeon has used a virtual driving simulator in DiVE to determine how soon people with bone fractures can safely return to driving.
Biomedical engineering researchers interested in improving cardiac care plan to build giant simulated hearts that they can “crawl” inside.
And the immersive technology is popular with local agencies, businesses and hospitals in the planning and design stages of projects.
Representatives with Triangle Transit, which is planning a three-county light rail project in Wake, Durham and
Jessica Riley, a former student, worked on a DiVE project in which she gave people the sensation of falling.
Orange counties, have visited DiVE recently to determine whether the technology could assist with future projects.
Juanita Shearer-Swink, Triangle Transit’s project manager, said seeing designs in a full-scale space will be more beneficial than looking at them on a computer monitor.
“With DiVE, we will be able to better understand new spaces and learn more about the impact of our designs,” she said. “Not only will we be more cost-effective, but we’ll also be able to use the technology to change environments, test designs in unforeseen conditions, and make changes to projects before we do anything in the real world.”
How the chamber works
The chamber is 10 feet on each side. Each wall, including the floor and ceiling, functions as a large computer screen. Six computers control full-color projectors – one per wall – and a seventh is the master computer.
To use DiVE at its full capacity, users wear stereoscopic glasses made with liquid crystals that provide depth perception.
Unlike 3-D glasses with red and blue lenses, the stereoscopic lenses are colorless, so the wearer can see all colors. The crystals also rotate, making the lenses alternate between transparency and opaqueness. That allows the eyes to fuse the 3-D imaging correctly, eliminating the blurry “ghosting” effect when video images double on the screen, Brady said.
Armed with a wand that tracks their movements and helps them navigate the virtual landscapes, users can be immersed in a believable visual fiction.
“Being inside the cube provides a large field of view,” Brady said. “This is one of the best ways to interact with computer representations of data.”
Why DiVE in?
The University of Illinois-Chicago (UIC) first unveiled the technology behind DiVE in 1991. Since then, the capabilities and features of immersion technology have expanded, said Andy Johnson, a computer science researcher and member of the Electronic Visualization Laboratory at UIC.
“There have been various changes in technology, and even 20 years later, people are still profoundly affected by what they see when they first walk into the cube,” he said. “It’s a space where people can explore and move around things naturally. It doesn’t feel like a computer.”
Immersive virtual reality has its drawbacks, Johnson said, such as a price tag between $1 million and $4 million and varying degrees of screen resolution. In fact, DiVE’s resolution – 1.1 million pixels per screen – is considered low for this type of technology, Brady said. The University of Iowa’s six-sided chamber has the highest resolution in the country with 16.7 million pixels per wall.
However, immersive environments let users examine information in a tangible way from multiple points of view. For example, General Motors has used the technology since the early 1990s to make design changes on full-size car models before building prototypes, Johnson said.
Brains, spiders and snakes
At Duke, Brady said, the DiVE is helping anatomy students learn complex body systems. A large 3-D brain floats in the middle of the cube, and students walk around it, observing how all its parts fit together. The program can spotlight singular parts to test a student’s knowledge of the brain’s structure.
Unlike a plastic brain model, the program can dissect the brain’s lobes, allowing students to see inside different sections.
Other experiments in the cube can have clinical applications.
A Duke psychologist interested in how people respond to frightening situations uses the cube to test whether patients with phobias react similarly in all environments.
Using DiVE, the researcher introduces spiders and snakes in three different immersive environments – a dining room, a forest and a backyard. According to Brady, the experiments have revealed how people associate fear with memories of locations and have proven immersive environments can be therapeutic tools in cognitive research.
“Although they know the spider or snake isn’t real,” Brady said, “the images are so accurate that many of them will back away quickly or even stomp their feet to get away.”
To read the Raleigh News & Observer article online: http://www.newsobserver.com/2010/12/13/859127/dive-cube-looks-like-a-holodeck.html
To read the Charlotte Observer article online: http://www.charlotteobserver.com/2010/12/12/1906890/sci-fi-fantasy-morphs-into-fact.html
Finding secrets of small worlds
Published in the Nov. 22, 2010, Raleigh News & Observer and the Nov. 22, 2010, Charlotte Observer
RESEARCH TRIANGLE PARK — Deep inside Duke Forest, 32 alternate universes sit in quiet rows. They look identical – each with a puddle, some land, a few plants.
But wholly imperceptible to the naked eye, these plots have distinct and important differences.
The realms, known as mesocosms, house individual types of nanoparticles as part of a research effort conducted by the Center for the Environmental Implications of Nano Technology ) based at Duke University.
CEINT uses laboratory and ecosystem experiments to determine how both natural and man-made nanoparticles – substances that are 1/10,000 the diameter of a human hair – affect the environment.
Nanotechnology has been a burgeoning field for nearly a decade, but very little research exists about how the tiny particles add up to affect our surroundings.
Identifying any changes is important, said Mark Wiesner, CEINT director and a Duke civil and environmental
Duke University scientists, from left, Ben Colman, Mark Wiesner, Benjamin Espinasse and Curtis Richardson check the status of an ecosystem being used to test the affects of nanoparticles at Duke Forest. They have 32 unique 'mesocosms' for testing. Photo Credit: Travis Long, Raleigh News & Observer
engineering professor, because more than 90 percent of some nanoparticles migrate up the food chain to humans.
“Nanotechnology and nanoparticles have given us huge benefits in medicine, applied mechanics, biotechnology and energy,” Wiesner said. “The question is what do we need to avoid so we don’t create environmental problems?”
The 2011 federal budget allots nearly $1.8 billion to nanotechnology research through the National Nanotechnology Initiative, and many investigations are being undertaken in North Carolina.
According to a 2009 Project on Emerging Nanotechnologies survey, the Research Triangle Park area has the fourth-highest concentration of nanotechnology companies, universities and research laboratories of all metropolitan areas nationwide, and North Carolina ranks in the top 10 states for nanotechnology activities.
Those analyses include the area’s research into the nanotechnology-environment relationship.
The nanoparticle trail
To track where and at what levels the environment absorbs nanoparticles, CEINT began the yearlong mesocosm project in August. The findings will also reveal the effects of nanoparticle presence.
Each waist-high, 3-foot-by-12-foot box contains nanoparticles coated with a different substance, such as titanium dioxide or silver. By following the coating’s trail through the mesocosm, Wiesner said, researchers can pinpoint how the nanoparticles either positively or negatively alter their surroundings and at what levels they might become toxic.
For example, nanosilver has anti-microbial properties and could be a powerful disinfectant. But if high concentrations of the particles wipe out all surrounding bacteria and viruses – even those that may be benign or beneficial – the effects on plants and animals is unknown.
The Duke investigators are monitoring the mesocosm changes as nanosilver and other nanoparticle levels increase, hoping to identify which substances are most harmful to the environment and humans, and at what level they become worrisome.
“Nanotechnology is a double-edged sword. Having and using particles this small can be useful, but on the other hand, it presents potential hazards,” Wiesner said. “A knife can cut your meals, but you can cut yourself with it, too.”
To better understand the implications of increased nanoparticle use, CEINT recently became home to the Transatlantic Initiative for Nanotechnology and the Environment. This international, $4 million safety program, sponsored by the U.S. Environmental Protection Agency and the United Kingdom Environmental Nanoscience Initiative, will determine how manufactured nanomaterials affect and behave in the environment.
Nanoparticles in the air
While many nanoparticles seep through soil, the fastest way for them to spread is through the air. But judging the effect of airborne nanoparticles is difficult because they travel long distances and deposit on surfaces in different concentrations, said Michele Ostraat, director of the Center for Aerosol Technology at RTI International.
“Aerosols play a large part in the environmental implications of nanotechnology,” Ostraat said. “The effects are wide-ranging because the nanoparticles become attached to leaves, rocks and roads, and sometimes are quickly put back into the air.”
Ostraat’s office has three projects to research how nanoparticles influence the air. Through miniaturized technology, RTI developed a personal exposure monitor that collects samples of substances in the air before, during and after a person has an asthma attack and identifies it as either naturally occurring or a synthetic aerosol. The data helps determine the levels at which nanoparticles pose an increased pulmonary or cardiovascular risk.
RTI also uses lightweight nanofibers to design more effective respirator filters. It’s easier for wearers, including firefighters, to breathe through the filters made with nanofiber weave, which is smaller than the diameter of most pollutants.
The organization’s latest initiative, Ostraat said, is a nanomaterial registry program that will compile details about the biological and environmental implications of individual nanoparticles in a single database.
“There’s so much information that it’s difficult to find a consensus about whether a nanomaterial is toxic,” she said. “By putting all of the biological and environmental details together, we can give researchers the extra information they need to make decisions about the particular nanoparticle they face.”
Researchers are making headway in understanding nanoparticles, but the environmental impacts are complex and will require deeper investigations, said toxicologist Nigel Walker, deputy program director for science at the National Toxicology Program in the National Institute of Environmental Health Sciences.
“This will be a challenge, and it will be a long time before we come to a final resolution of whether nanoparticles are safe or unsafe,” Walker said.
To read the full Raleigh News & Observer article online: http://www.newsobserver.com/2010/11/22/818313/finding-secrets-of-small-worlds.html
High tech hard hats put on another safety hat
Published in the Oct. 25, 2010, Raleigh News & Observer and the Oct. 24, 2010, Charlotte Observer
BY WHITNEY L.J. HOWELL – CORRESPONDENT
DURHAM — Hard hats have long protected workers’ heads in calamities, and now engineers at Duke University are aiming to turn the hats into alarms when danger is present.
According to the Occupational Safety & Health Administration (OSHA), more than 1,100 workers die and thousands more are injured on construction sites annually. A modified hard hat, dubbed the SmartHat, could reduce these numbers by sounding a warning when workers venture too close to large equipment.
“Safety concerns are high when people and heavy equipment share the same space,” said Matt Reynolds,
The SmartHat, designed by a Duke University engineer, would send an alarm to a construction worker who gets too close to heavy equipment. Photo Courtesy: Duke University
a Duke electrical and computer engineering researcher and SmartHat’s designer. “Most accidents and injuries occur because machine operators either don’t see workers or workers are faced away from the equipment.”
The SmartHat technology piggybacks on existing wireless networks at construction sites that monitor vehicle locations. Each piece of heavy machinery carries a wireless transmitter that broadcasts its location.
A silicon microprocessor, attached with Velcro to the crown of the SmartHat prototype, captures these free-floating radio-frequency waves with antennas. If the microprocessor determines the wearer is too close to equipment, it emits a high-pitched alarm that speeds up as man and machine move closer together.
“The beeping is an annoying sound that workers can hear through the noise of the work site,” Reynolds said. “If we mount the microprocessor in the hard hat, we create an echo chamber to amplify the warnings.”
However, the microprocessor’s ultimate location must be chosen carefully, said Jochen Teizer, a civil and environmental engineer at the Georgia Institute of Technology. OSHA requires that nothing compromise a hard hat’s ability to protect the wearer’s head during an accident.
“Including the SmartHat technology can’t create any danger to the wearer, such as creating a pinch point that could cause injury,” Teizer said. “For the technology to be feasible, you need to integrate it inside the hard hat. Integrating it into the plastic would be the final solution.”
Microprocessors should also have an extensive range, he said, to alert workers to fast-moving machinery.
To read the Raleigh News & Observer story: http://www.newsobserver.com/2010/10/25/758724/hard-hats-put-on-another-safety.html#ixzz13NKqs8E2
To read the Charlotte Observer story: http://www.charlotteobserver.com/2010/10/24/1784884/hard-hats-put-on-another-safety.html
Tiny DNA circuits offer high speed
Published in the July 19, 2010, Raleigh News & Observer and the July 19, 2010, Charlotte Observer
BY WHITNEY L.J. HOWELL – CORRESPONDENT
Imagine a cell phone that connects a call, or a computer that sends an e-mail at the speed of light. Work conducted by a Duke University engineer could usher in this new wave of electronic prowess.
Currently, silicon-based circuits power electronic devices. But there is a limit to how fast they can work and how small they can be. Using circuits made of DNA bypasses both problems, said Chris Dwyer, a researcher in Duke’s electrical and computer engineering department.
“DNA gives us the tools to make these information circuits as small as a protein,” Dwyer said. “Because DNA self-assembles, these circuits are faster to create, and they have an incredible capacity for sensing and processing.”
Mixing tailored segments of DNA together produces waffle-like structures that function as scaffolding for other sensors. Adding light-sensitive molecules, called chromophores, ignites the waffle structures’ programmable properties, turning them into switches with a wide array of applications other than electronic capabilities, including biomedical and computational capacities.
The waffle structure can be custom-made to detect different molecules in saliva, blood or urine. These structures
This waffle-like structure, made of DNA, can be made as small as a protein, says Duke University researcher Chris Dwyer. Photo courtesy of Duke University.
could be used with a cheek swab, Dwyer said, and a health practitioner could get same-day lab results for a battery of tests that it currently takes a week to complete.
The waffles also can be used as unique, sophisticated electronic encryption devices, he said.
The potential for these DNA-based circuits is substantial, said Jay Narayan, chairman of materials science in N.C. State University’s department of materials science and engineering. Making them work well for long stretches of time could be the hard part.
“Making this practical will be a challenge because DNA exists, by nature, in a solution, and electronic processes must have a solid surface to work,” he said. “We must also be careful because DNA is alive, and it can’t sustain the high temperatures that silicon-based structures endure to allow electronic devices to work.”
Narayan also said extending the DNA’s lifetime would be necessary to make it a plausible choice for electronic or clinical use.
For the Raleigh News & Observer article: http://www.newsobserver.com/2010/07/19/587472/tiny-dna-circuits-offer-high-speed.html
For the Charlotte Observer article: http://www.charlotteobserver.com/2010/07/19/1570543/tiny-dna-circuits-offer-high-speed.html
Tiny glass beads can deliver drugs
Published in the May 10, 2010 Raleigh News & Observer & Charlotte Observer
BY WHITNEY L.J. HOWELL – CORRESPONDENT
DURHAM — Anyone who has made rock candy in a kitchen chemistry experiment is familiar with the transformative process of evaporation. Now a Duke engineer is using a similar approach to make something more sophisticated: protein-based, intravenously delivered pharmaceutical drugs in tiny glass bead form.
By putting proteins dissolved in water into a larger solution of the organic solvent octanol, David Needham, an engineer and chemist at the Duke University Pratt School of Engineering, discovered he could remove the water, leaving behind a spherical, protein glass bead. The process is called glassification.
“With this method, we can control the size of the protein particles, as well as the rate of dispersion, for more efficient
COURTESY OF DUKE UNIVERSITY - A process developed at Duke University creates these tiny glass beads of protein-based intravenous drugs.
drug delivery,” Needham said. “We’ve also determined that glassification helps proteins hold on to their work abilities better than other protein preservation methods.”
Michael Bishop, director of medicinal chemistry for GlaxoSmithKline Research & Development, said the pharmaceutical company is in preliminary discussions with Needham to see if glassification can make drug delivery and production more efficient and less expensive.
Protein-based drugs include insulin or the cancer drug Herceptin. Currently, the ingredients must be freeze-dried into a powder. The protein powder must be hydrated to work as an injectable drug, but it often clogs the delivery syringes. Using glass beads is more efficient because they create a thinner substance that won’t block syringes, Needham said.
John Carpenter, a professor of pharmaceutical biotechnology at the University of Colorado Denver, said the cost of shifting to Needham’s technology may be prohibitive, at least until the process proves viable in large-scale testing.
“It sounds good on paper, but for traditional vaccines, drugs and therapeutic proteins, I don’t see [Needham’s] discovery replacing the current system,” Carpenter said. Still, he said, the development holds promise.
“I’m excited that his engineering can be applied to other approaches that have failed because they haven’t been able to control particle size, like those that blast drugs through the skin,” Carpenter said.
To read the story online: http://www.newsobserver.com/2010/05/10/475248/tiny-glass-beads-can-deliver-drugs.html or http://www.charlotteobserver.com/2010/05/10/1426027/tiny-glass-beads-can-deliver-drugs.html
Who am I?
I’m a seasoned reporter, writer, freelancer and public relations specialist with a master’s degree in international print journalism from The American University in Washington, D.C.
I launched my journalism career as a stringer for UPI on Sept. 11, 2001, on Capitol Hill. That day led to a two-year stint as a daily political reporter in Montgomery County, Md. As a staff writer for the Association of American Medical Colleges, a public relations specialist for the Duke University Medical Center and the public relations director for the UNC-Chapel Hill School of Nursing, I’ve earned in-depth experience in covering health care, including academic medicine, health care reform, women’s health, pediatrics, radiology, and Medicare.
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