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.”
Duke’s Steve Nowicki finds out what songbirds have to say
Published in the Feb. 4, 2013, Raleigh News & Observer and Feb. 4, 2013, Charlotte Observer
By Whitney L.J. Howell
Deep in a North Carolina marsh, a lone swamp sparrow sits on his perch in the middle of the water. He’s singing his usual song. But he’s also aggressively flapping one wing, trying to incite a nearby male into action. Onlookers are watching – just to see what happens.
However, this is no ordinary territorial scuffle. This is bird research. The sparrow on the perch is a robot, and the chief, hip wader-clad onlooker – who is also in control of the robot’s movements – is Steve Nowicki, Ph.D., a biology, psychology, and neurobiology professor at Duke University. He’s testing whether the wing flap will actually prompt a fight.
According to Nowicki, birdsong and signaling have a surprisingly close relationship
Stephen Nowicki, Ph.D., Professor Dean of Undergraduate Education
Jared Lazarus – Duke Photography
with human speech.
“It’s an unexpected and remarkable model for human speech control, development and perception,” he said. “Birds also learn their songs in much the same way humans learn to speak, and that’s an unusual trait. They have to learn their language from their parents.”
His research, though, isn’t about merely studying how birds behave and communicate. He and his team watch signals and behaviors; they run simulations and analyze hormones; they record neurons and assemble protein sets. They’re deciphering how birds promote their survival and reproductive success. In short – they’re studying evolution, past and present.
Why birds?
Nowicki, who is also dean and vice provost of undergraduate education, was almost the bird researcher who wasn’t. As a student at Tufts University in Boston, he was a declared music major. Late in his collegiate career, he discovered a love of biology – particularly the brain and behavior – and raced to complete a major in the subject. He then pursued his graduate degree in neurobiology at Cornell University.
It was there he was first introduced to the siren song of birds. When it comes to communicating, birds have far less to say than humans. But they express themselves in equally complex ways, Nowicki said.
“Humans use complicated signal communication, and we use an array of sounds to create words that have rich meanings,” he said. “When you look at sparrow songs – the number of notes per second and the frequency – it’s just as complicated as human speech. They’re just not saying much.”
All the same, they’re getting their points across.
Songs, signals
In addition to the aggressive response the swamp sparrow’s wing flap provokes, the absence or introduction of song or even a physical attribute can prompt birds to behave differently, Nowicki said.
Birds, like most animals, are territorial and will, in most cases, defend their turf. But how will neighboring birds respond if a battle ensues? Will they come to help or avoid the fight? Will they treat the male differently if he loses to the interloper? Researchers can test this reaction, Nowicki said, by removing a bird from its environment, playing a recording of another male’s song, and, then, reintroducing the bird to see how the others respond.
“It’s interesting to see what happens, because no one wants a floating male in the neighborhood,” he said. “Research has shown that with some birds, peer birds are more wary of the winner, but they might also try to encroach on a loser’s territory.”
A swamp sparrow states his case: According to Duke University biologist Steve Nowicki, birdsong and signaling have a surprisingly close relationship with human speech. PHOTOS BY ROB LACHLAN
And, just as with other species, birds can use their physical attributes to signal to and communicate with each other. For example, a trait, such as a bright red neck and throat commonly seen in the male house finch, can broadcast a bird’s prowess or superior qualities. The red-throated male finch does attract more females, Nowicki said, but it isn’t because of the color. The pigment comes from a carotenoid-rich diet that gives these males a stronger immune system, making them better mates.
Male song sparrows use their song repertoire in much the same way. The more songs they learn and exhibit, the more attractive they are to females. The reason, Nowicki said, is that birds with larger song selections appear to be smarter. They simply learn songs faster.
“Males who sing better have better developed brains, and in theory that makes them better mates,” he said. “We’re still working out why having a better brain for learning song is better for the female, but it’s clear females prefer these males as their mates.”
Impact on human activity
Understanding the role and importance of birdsong and signaling doesn’t shed much light on the evolution of human communication, but knowing what songs and signals mean to birds can directly affect human choices and behavior.
For example, researchers have evidence that stress directly affects a bird’s ability to develop song, which can ultimately impact pair bonding and mating. If scientists study the way birds living in both polluted and pristine environments sing, the data could play a role in accurately evaluating ecosystem health.
This knowledge can also impact wildlife preservation efforts. It isn’t enough to allocate a certain amount of space to a population based only on the number of animals surveyed. There are often other factors at work, Nowicki said. In the case of the small warbler ovenbird, it’s important to know that females won’t be setting in an area with fewer than 10 males. This type of information can significantly alter conservation efforts, he said.
Regardless of how the research of birdsong is used, Nowicki said, his work constantly reminds him of how intertwined birds and music are with our surroundings.
“I keep coming back to birdsong not simply because it’s a good model,” Nowicki said. “When I wake up in the morning and hear birds singing, it’s part of the wonderful aesthetic world we live in, and my job to learn more about it is a privilege.”
If mice could talk and sing… (Well, maybe they can)
Published in the Dec. 24, 2012, Raleigh News & Observer and Charlotte Observer
By Whitney L.J. Howell
It’s a pretty common scene in a bar or club on any given Friday or Saturday night. One, maybe two, guys are eagerly chatting-up the hot girl with the cocktail in her hand. They’re trying their best to be witty, to be charming, to do anything to potentially win her affections – even using each other’s best lines.
Until now, however, no one considered that mice might be doing the same thing. But they could be. In fact, they’re probably more aggressive about it. Male mice don’t stop at pleasant conversation. They’ll chase a female while singing to her and trying to smell her.
Strange as it all may sound – and it does defy conventionally held beliefs about the ability of mice to “talk” – Erich Jarvis, Ph.D., neurobiology associate professor at Duke University, and his team
Erich Jarvis, Ph.D., neurobiology associate professor at Duke University, and his team have discovered that mice may have some of the same brain features that humans and song birds use for vocalizations and pitch changes. Erich Jarvis, Ph.D., neurobiology associate professor at Duke University, and his team have discovered that mice may have some of the same brain features that humans and song birds use for vocalizations and pitch changes. (2006 AP file photo)
have discovered that mice may have some of the same brain features that humans and songbirds use for vocalizations and pitch changes.
“It’s accepted dogma that humans and songbirds are the only beings that have the four brain areas needed to produce vocalizations,” said Jarvis, who is also a Howard Hughes Medical Institute investigator. “Based on our research, we believe mice have more limited versions of these behavior and brain traits.”
The HHMI, National Science Foundation, and the National Institutes of Health funded Jarvis’ research.
The findings indicate that male mice may be able to learn how to change their vocalizations to match another male mouse. If correct, scientists may be forced to reconsider a belief they’ve held for 60 years – that vocal learning is unique to humans and a small cadre of songbirds.
The experiment
With his former grad student Gustavo Arriaga, Jarvis used gene expression markers, which lit up neurons in the motor cortex – the part of the brain involved in planning, control and voluntary movement – of each mouse’s brain while they sang. When these song-specific neurons were damaged, the mice couldn’t keep their songs on-pitch or consistently repeat them, verifying their connection to vocalization.
In addition to the markers, the team injected a tracer to map the signals that controlled the songs as they migrated from neurons in the motor cortex to the brainstem and on to the larynx muscles. According to Jarvis, this direct channeling from motor cortex to larynx was the biggest surprise and puts into question whether these projections in mice work the same way as in humans and birds: Can mice learn vocalizations?
To make this determination, the team first had to record the sounds
Post-doctoral research assistant Gustavo Arriaga, left, and neurobiologist Erich Jarvis study singing mice at Duke University’s Bryan Research Building.
JARED LAZARUS – DUKE UNIVERSITY
mice make. They placed a pair of male mice in a cage with a single female to prompt communication and used a 4-inch high-sensitivity microphone to capture the sounds. The powerful microphone was necessary because mice “speak” at a frequency between 30 and 40 KHz – too high-pitched for humans to detect. Humans hear sounds between 14 and 15 KHz.
Jarvis’s team monitored 12 pairs of male mice over an 8-week period to see whether they began to imitate each other or the pitch of their songs converged. They conducted the experiment twice, and by the eighth week, he said, the less-dominant mouse had modified its song to emulate the dominant male.
By digitally modulating the recordings to a frequency audible to humans, the investigators demonstrated that, by the end of the experiment, the male mice had virtually identical songs.
“The mice were changing their pitch so the smaller animal matched the song of the larger male,” Jarvis said. “This is a simple form of imitation – it’s pitch. Until now, it was thought that they didn’t have this ability for vocal learning.”
The controversy
Not everyone agrees with these findings, however. Kurt Hammerschmidt, a vocalization expert at the German Primate Center, is reticent to fully accept that mice can be true vocal learners. The problem, he said, is that Jarvis’ team simply didn’t analyze a large enough number of mice.
“Fewer animals is OK in neurobiological studies because we know anatomical structures found in one animal are also present in other animals,” Hammerschmidt said. “But with behavioral studies, we need more animals to look at motivation, arousal and experience.”
Hammerschmidt and other scientists worldwide have conducted experiments similar to Jarvis’s and have not replicated his findings. Hammerschmidt also disagrees that pitch convergence alone indicates that mice are vocal learners.
“All other studies focused on male courtship songs failed to find any evidence that learning is involved in the development of these vocalizations,” he wrote. “None of all other terrestrial mammals, except humans, are able to produce new sounds.”
Future implications
Additional research is needed, Hammerschmidt said, to verify whether Jarvis’s findings are correct.
If Jarvis and his team are correct, though, these findings could impact both science and health care.
Although mice don’t have the same speaking ability as humans have, understanding their potential capacity for vocal learning could shed light on how speech works in people, as well. It could open the door for further research into the brain’s circuitry and the basic principles of speech, Jarvis said.
The greatest impact of this research, however, could be its effect on neurological disease, he said. In particular, autism is the brain disorder that has the biggest impact on speech, and the NIH and Congress have invested millions to study the causes and biological makeup of this condition. In these studies, investigators have been able to take the gene variant from a child with autism and put it into the mouse genome, but they’ve been unable to pinpoint which area of the brain is affected. This research eliminates that limitation.
“Now, we have the brain pathway for them to look and play around with,” Jarvis said. “It could open the door for some gene drug therapy on this part of the brain or help determine how we can affect the whole system.”
N.C. State researchers develop better tool for hurricane prediction
Published in the Nov. 5, 2012, Raleigh News & Observer and Charlotte Observer
By Whitney L.J. Howell
Meteorologists last week scrambled to give the public as much information as possible about what they could expect from Hurricane Sandy.
Where would it hit? How strong would it be? What damage would it inflict? What would be the likelihood of a powerful storm at this time of year?
Using current methods, there was no way meteorologists could have foreseen a storm as massive as Sandy.
But they will be better prepared in the future to answer these questions – not just about one hurricane, but about all hurricanes during a given year. Thanks to a new predictive model from researchers at N.C. State, storm watchers and scientific investigators alike will be able to forecast a season’s hurricane activity with 15 percent more accuracy over existing models.
The goal of the research, published in Data Mining and Knowledge Discovery,
Nagiza Samatova, an N.C. State associate professor of computer science, is co-author of the hurricane modeling report. Courtesy: NCSU
investigators said, is twofold.
“Hopefully, this approach will give policymakers, insurance providers, and people responsible for preparedness a more reliable method for anticipating hurricane activity,” said Nagiza Samatova, N.C. State associate professor of computer science and study co-author. “We also hope it will impact climate change modeling and work that can predict what climate changes we can anticipate.”
New system vs. old model
Despite the number of storms that happen annually, historical data surrounding hurricanes is surprisingly small. Meteorologists currently use information dating back to 1950 to estimate how many storms will occur during a single hurricane season. Data about temperature, humidity and precipitation from a small number of hot spots are run through a statistical algorithm to predict how many storms the East Coast will experience. Each hot spot is a location around the globe known to be the origination points for hurricane activity.
“The problem with this model is it has a relatively small amount of data to work from,” Samatova said. “Sixty or so years of information from a few areas of activity worldwide isn’t enough to really predict how a hurricane season will play out.”
Consequently, determining which information correlates to low activity and what indicates high activity has been challenging. The new N.C. State model, however, aims to alleviate that problem by pulling data from nearly 10,000 points across the globe. Samatova likened this model to a social network where each node is a different person. Just as more is known about an individual and how they connect with others when they provide more details within a social network, a growing bed of meteorological knowledge will help scientists forecast from where the most intense storms will spring.
By entering historical data into the new algorithm, Samatova and her N.C. State colleague, Fred Semazzi, a professor of marine, earth, and atmospheric science, have confirmed that their model predicts hurricane activity with 80 percent accuracy over the 65 percent accuracy rate of traditional methods.
Benefits of the model
In addition to providing more precise estimations for storm activity, the N.C. State model has also helped identify previously unknown hotspots, Samatova said. For example, there are several points around southern Africa that scientists never realized directly affected hurricane activity in the North Atlantic region – the area covering the East Coast.
Professor Fred Semazzi of N.C. State, in front of an image of Hurricane Fran: Adding historical data and unusual characteristics into the new algorithm makes the N.C. State model better at predicting hurricanes. Courtesy: NCSU
“Identifying new hot spots is an advantage, because now we’re able to discover new, interesting features of what makes a location a hot spot that we didn’t already know,” she said. “This way, we’ll be able to build out even more models, and we’ll be better able to identify high-activity or low-activity seasons.”
Activity levels are a sliding scale based on geographic region. In the North Atlantic, eight or more hurricanes equates to high activity; five to seven storms is average; and anything less is considered low activity.
Through the new model, researchers also identified additional characteristics that can help predict hurricane activity. Incorporating unusual behaviors, such as strange patterns or unusual storm edges, can also enhance the model’s predictive ability.
“By using additional factors, we hope to learn more about what influences a hurricane’s behavior,” Samatova said. “This could allow for an impact on climate change work if we’re able to forecast storm behavior well into the future.”
New models needed
Previous research from the University of Notre Dame supported Samatova and Semazzi’s work that new predictive modeling is needing to accurately forecast not only the occurrence, but also the impact of hurricanes. Although that research focused on the Gulf Coast region and anticipating storm surge, researchers emphasized the need for more data gathered from an extensive number of points across the globe.
“Accurate model forcing is necessary to simulate the correct storm surge propagation,” wrote Jesse Feyen, a former Notre Dame doctoral student and current researcher in the National Ocean Office in the National Oceanic and Atmospheric Administration.
In the wake of Hurricane Katrina, researchers at the Massachusetts Institute of Technology also began asking questions similar to the ones N.C. State’s model aspires to answer. MIT’s team seconded Feyen’s assertions and noted one practical concern for which N.C. State’s model could eventually be greatly beneficial.
“There is a time component. Scientists simply cannot predict hurricanes early enough for cities to be completely prepared,” they said. “There is no certainty in the position of a hurricane until it is too late to respond. Hurricane predictions in the future need to be more accurate earlier on in the forecasting process.”
Optical Mammography Promises Specific Images, More Comfort
Published on the Oct. 8, 2012, Diagnostic Imaging web site
By Whitney L.J. Howell
Optical mammography isn’t new technology, but researchers at Tufts University School of Engineering have given it an upgrade. Now, the technique allows radiologists to obtain mammography images without radiation and with greater patient comfort.
With the support of a grant from the National Institutes of Health, investigators created a stand-alone, portable scanner that uses near-infrared light — rather than ionizing radiation — to scan the breast. Specialized software, using an algorithm based on optical information, translates the intensity of the transmitted light into breast images.
Patients are currently being recruited for a clinical study that will look at the
Shown is an optical mammography image of hemoglobin oxygenation of a duct carcinoma in situ (DCIS). The boxed area corresponds to the cancer location and indicates lower values of hemoglobin oxygenation. For cancerous tissue that is associated with abnormal hemoglobin concentration and oxygenation, optical mammography can be used to help diagnose breast cancer and also indicate how well a patient responds to breast cancer chemotherapy. (Credit: Sergio Fantini, PhD, professor of biomedical engineering at Tufts University)
scanner’s efficacy in differentiating between healthy and cancerous tissue, as well as benign lesions.
The goal, according to lead investigator and Tufts biomedical engineering professor Sergio Fantini, PhD, is to potentially provide more specific breast screenings that prompt a lower number of false positives. That change could ultimately result in fewer follow-up appointments and biopsies than traditional mammography.
“For breast screening, X-ray mammography is the gold standard, and conceptually, this is really the same thing,” Fantini said. “But the information content that we obtain with optical mammography is more related to the hemoglobin in blood and what it tells us about blood flow and oxygenation.”
In addition, optical mammography can also give you information about the amount of water and fat in breast tissue, he said. You can discern between water and fats, as well as high and low oxygen levels by how much light the tissues absorb — all details that help you diagnose cancers. The clinical study is designed to determine if Tufts’ optical mammography scanner can readily differentiate between malignant and benign lesions.
To read the remainder of the story at its original location: http://www.diagnosticimaging.com/womens-imaging/content/article/113619/2106744
Former NASA historian says agency’s future lies with unmanned projects
Published in the Sept. 17, 2012 Raleigh News & Observer and Charlotte Observer
By Whitney L.J. Howell
We asked Alex Roland, professor emeritus of history at Duke University, to put the current Mars Curiosity mission in a perspective. Roland is a former NASA historian.
Q: What are the benefits of unmanned space exploration, such as the Mars Curiosity?
One question has driven all current space exploration: Was there ever, or is there now, life on Mars? It’s likely if there were, it’s disappeared, but we might find evidence. That would have enormous implications for the space program and for the human race and condition. It would suggest we’re not unique in the universe.
Such a discovery would increase NASA’s emphasis on getting the country to agree to a manned Mars mission. NASA sees itself as having had a golden age with the Apollo program. Ever since, it has tried to find something else to capture public imagination to justify a large increase in our space activity spending. Curiosity plays an interesting role because if it finds evidence, NASA can increase its manned mission push. But Curiosity is such a capable exploration vehicle, and it’s so much cheaper and less dangerous than a manned mission, that many of us believe we should invest in more Curiosities.
Q: What’s the advantage of unmanned missions?
Whenever you send people to space, the expedition’s purpose changes. To explore Mars, we can send up as many remotely controlled vehicles as necessary. They’re uniquely designed for exploration. A manned mission must get people there and back safely. That trumps all else, and it limits exploration. Humans can only do safe exploration. Their exploration time is limited because they must return to Earth soon. It also limits the equipment sent up because astronauts need a lot of life support. For exploration, we’re better off sending custom-designed, remotely controlled, automated spacecraft. There’s nothing humans can do on Mars that a machine can’t. Sending people increases risk and diverts the mission’s goal.
Q: Are there potential technological gains from the Curiosity mission?
Investing in science and technology, especially research and development,
This panorama image of Curiosity’s lower front and underbelly combines nine images taken by the rover’s Mars Hand Lens Imager on Sept. 9. Fine-grain Martian dust can be seen adhering to the wheels, which are about 16 inches wide and 20 inches in diameter. The bottom of the rover is about 26 inches above the ground. On the horizon at the right is a portion of Mount Sharp, with dark dunes at its base. The imaging by MAHLI was part of a week-long set of activities for characterizing the movement of the arm in Mars conditions.
always produces spinoff. Second-order consequences and unanticipated technological applications can be useful in other fields. But that comes from any R&D. NASA’s spinoff record isn’t great. It has claimed the dollars it has invested produced more spinoff technology, but that mostly isn’t true. There’s nothing specific NASA does that makes R&D any more productive.
Q: Could this Mars mission be seen as a relaunch of space exploration?
Whenever I hear of manned Mars missions, my first question is, “Why?” What will we do? Will it be like Apollo where we send humans there and bring them home safely, and that’s the end?
NASA maintains manned Mars missions will be part of a permanent space colonization program. That begs the question of why colonize Mars? Sending humans there to take pictures, scoop soil, and return safely will cost hundreds of billions of dollars. An initial colonization mission would cost probably around $1 trillion just to get started.
So, it’s reasonable to ask the purpose and benefit of having people on Mars. A good comparison is the International Space Station. We paid more than $100 billion to put it up there and never found a good use for it. Within a decade, we’ll likely abandon it, let it decay in orbit, and burn up in the atmosphere. If we can’t find a good use for the space station that’s comparatively close and safe – even though we’ve lost two space shuttles and crews going there and back – how do we think we’ll find a good use for humans on Mars?
Q: What continues to drive NASA toward manned exploration? Are we still searching for our place or role in the universe?
That’s exactly it. When NASA sent the first crew to the space station, it stressed this reflected both the agency’s and our country’s place in history. It emphasized this was the beginning of permanent human space habitation. It believed from then on humans would be in space and people would look back and remember America, NASA, and the space program.
But there’s no commitment to fund the space station very far into the future. It’s too expensive to maintain, and it’s not doing anything useful.
NASA will argue strenuously to maintain a space presence. We all love NASA. We love what they do and think they’re good and capable. But the public has a right to ask what we’re getting for our investments, especially when budgets are stressed.
Q: In the last decade, space exploration has shifted from government-funded enterprise to the private sector. Will this continue?
I’ve long been skeptical that private companies without government subsidy can make money flying in space. There isn’t that much money to be made. It’s a big business, but it’s not what most private venture firms are motivated by. Often, it’s idealistic, very wealthy people with lots of money to invest.
They grew up in the space age. They want the same permanent space presence NASA wants, and they’re going to help make it happen. I think we’re seeing evidence they can build launch vehicles and operate them more cheaply than NASA. But do they have a business model for sustainable programs and making money?
None will reveal how much they’ve spent, and without long-term, sustainable business models, venture capital isn’t attracted. It’s unclear how many companies will make money.
NASA’s trying to help them because if companies assume routine activities, like launching satellites or resupplying the space station, then NASA can divert funding to futuristic enterprise, including manned Mars missions. Perhaps NASA has enough business to keep them going for a while, but not enough for long-term profit. One strange peculiarity of modern technology is the satellites we launch now are so big and powerful we don’t need as many of them as we used to.
Q: What can NASA do to reignite or reinvent itself?
What many at NASA only say privately is the public often doesn’t appreciate NASA’s unmanned spacecraft magnificence. It has transformed how we understand the universe and presented research possibilities, but NASA’s believed its public and congressional support and budget depend on manned space exploration.
NASA has believed people don’t care about space science, communication and weather satellites. But these technologies give us today’s world. Manned space flight has been little more than circus or stunt. Astronauts go up, float around, and return without accomplishing much.
Curiosity exemplifies how exciting unmanned space activity is, and how interested the public can be if NASA educates them.
The time is ripe for tomato genetics
Published in the July 16, 2012, Raleigh News & Observer and Charlotte Observer
By Whitney L.J. Howell
There’s no doubt humans top the evolutionary food chain. But people are, by no means, the most genetically hefty beings on Earth.
Recent research from a North Carolina site of a global plant-development company revealed the tomato has at least 7,000 more genes than humans. And, decoding that genome could make picture-perfect, grocery-store tomatoes taste as good as deformed, homegrown ones.
Since 2008, researchers at Syngenta’s biotechnology hub in Research Triangle Park, along with other scientists worldwide, have analyzed the genetic sequence for two tomato varieties – Heinz 1706, the tomato used in ketchup production, and its closest wild relative, Solanum pimpinellifolium, found in Peru. These investigations revealed tomatoes boast 31,760 genes, many of which scientists are analyzing to determine how they control the fruit’s growth.
“Tomatoes are a model crop that, in many ways, is well understood,” said Bob Dietrich, Ph.D., senior research scientist at Syngenta. “Our main reason for conducting this research is so we have enough information to develop the tomatoes we want.”
Why the tomato?
Although the genetic structures are different, tomatoes are closely
Becky Cade prepares tomato leaf samples for testing at Syngenta’s Research Triangle Park laboratory. PHOTO CREDIT: Syngenta
related to potatoes, tobacco plants, peppers, eggplant and nightshade – a toxic member of the potato family. According to Rebecca Cade, a Syngenta research scientist, studying the tomato genome can increase the knowledge base around these and many other plants.
“The tomato is an excellent archetype for fruiting plants,” she said. “There’s been lots of research on how it grows, and scientists and breeders will be able to apply the knowledge gained from studying its DNA to other fruiting crops.”
Syngenta’s team has a multifocused goal with this research, looking for genetic answers to the tomato’s shelf-life, size and firmness. However, the company’s chief concern is helping farmers bring a better-tasting product to market.
“Once we have the finished genome sequence, we’ll be able to tell the differences between a beefsteak tomato and a cherry tomato,” Dietrich said. “With that information, we’ll be able to make a beefsteak with a cherry flavor or vice versa.”
Ultimately, Cade said, the goal is to allow breeders to do predictive breeding.
“In this scenario, someone would say, ‘I need a tomato with this maturity date, this sugar content, and resistant to this pathogen,’” she said. “By looking at our tomato genomes, you can take various seed lines, cross them, and get this type of desired outcome.”
Sequencing the code
According to Dietrich, efforts to decode the tomato genome began in 2009. The work was initially geared toward creating a rough draft of the genetic map that would eventually help breeders create more marketable versions of the fruit. In 2010, Syngenta and its partners teamed up to use different technologies that build upon each other’s strengths and weaknesses, he said.
Syngenta’s global collaborators sequenced 70 percent to 80 percent of the tomato’s DNA using technology that focused on longer reads – segments of DNA long enough to identify when gene components (the bases adenine, guanine, cytosine and thymine) begin to repeat. Scientists were able to identify significant differences among cultivated tomato lines with this amount of data.
But the gaps in the genome still left unanswered questions about which genes could control a plethora of tomato characteristics, he said. Using technology from the genetic-analysis company Illumina, Syngenta analyzed the final one-third of tomato genes using a technique that looks at smaller segments of DNA. In this case, Cade said, this short-read sequencing examined DNA strips with up to 800 bases.
“DNA sequencing is really like a puzzle – it takes a lot of work to make sense of it,” she said. “If you have short reads, you can have billions of pieces and maybe 1,000 of them look exactly the same. With longer-read technologies, you can have bigger pieces that show repeat and unique sequences. So, you need long reads to complement the short reads to get a full picture.”
This long/short sequencing technique is beneficial, Dietrich said, because it opens the door for other tomato varieties to be sequenced more easily. Researchers will now be able to analyze the DNA many other types of tomatoes in far less time and for less money.
While knowing which genes could improve the taste and appearance of tomatoes in the grocery store, understanding the fruit’s DNA and how to manipulate it could impact the global food supply, said Jim Giovannoni, Ph.D., plant geneticist at the Boyce Thompson Institute for Plant Research associated with Cornell University. The majority of Giovannoni’s work is also focused on decoding what part of the tomato genome is responsible for ripening.
Toward a ripe future
“Understanding and potentially controlling the ripening process genetically could increase food security for people in other countries who, at certain times, have a lot of food available but can’t eat it due to rot,” he said. “They don’t have the infrastructure and money to store food like we do, so a genetic solution could have a real effect on food security in the developing world. It would also make our First World issue of shipping food around a less expensive process.”
Specifically choosing certain traits that alter taste, color, texture, and ripening does present trade-offs, however, he said. For instance, a tomato bred to last longer on the shelves might not taste as good. Or one bred for a more home-grown flavor might not have a uniformly-colored skin.
“The reality is that, with this research, we understand more about what genes are responsible for what characteristics, and we can give breeders the tools for selecting certain traits,” Giovannoni said. “There can still be negative outcomes, no matter how small, but breeders can now take the selection of characteristics in their traditional breeding programs to a different level.”
N.C. State researchers develop a better test for cat scratch fever
Published in the June 25, 2012, Raleigh News & Observer and Charlotte Observer
By Whitney L.J. Howell
“Cat Scratch Fever” might be best known as a catchy song, but the infection of the same name, scientifically known as Bartonella – is an easy-to-catch infection caused by a common, hard-to-detect microbe. But a test developed by N.C. State researchers could make it simpler to pinpoint the pathogen and treat the resulting symptoms.
Using a patented insect medium and a sensitive, sophisticated DNA analysis tool, N.C. State investigators have developed a Bartonella diagnostic test for humans. The goal is to identify Bartonella infections faster and more accurately, and a partnership with Research Triangle Park-based company Galaxy Diagnostics, Inc. could make the test widely available.
“This microbe is one of a handful that physicians who specialize in chronic disease
There are more than 25 known Bartonella strains, and roughly nine have been linked to disease development in humans. The difficult-to-detect pathogen is transmitted by blood-sucking insects. Individuals with frequent animal exposure, especially to cats, can be at high risk.
PHOTO CREDIT: JANET BLACKMON MORGAN – MCT
look at now, but a lot of doctors don’t test for it because of the high false-negative rates. If you don’t know exactly what to look for or if you don’t have the tools, why look for it?” said Amanda Elam, Galaxy Diagnostics president. “We think we’ve found a way to identify the bacteria, and we’re helping to find it in patients with this test.”
Currently, there are more than 25 known Bartonella strains, and roughly nine have been linked to disease development in humans.
However, diagnosis is challenging because it only takes a few Bartonella particles to prompt an infection. Small amounts mean even highly sensitive tests, such as DNA analysis with the help of polymerase chain reactions (PCR), often yield false negatives.
“Locating Bartonella is like finding a needle in a haystack with the infection being the needle and the haystack being the patient,” said Ed Breitschwerdt, internal medicine professor at N.C. State’s College of Veterinary Medicine. “If the haystack is too big and there are only a few needles, PCR will miss the infection more often than not.”
How the test works
Getting a Bartonella diagnosis faster means relying on the bugs that carry it, said Breitschwerdt, who led the test’s development team.
“During our 15 years of research, it became obvious many different insects – sand flies, lice, fleas, biting flies on cattle, and ticks – were confirmed Bartonella carriers,” Breitschwerdt said. What made his research different was finding the way to grow Bartonella more quickly in a Petrie dish.
“We asked whether Bartonella would be happier in an insect-growth medium compared to mammal-growth. It’s not too sophisticated a question, but it proved important because the answer was yes.”
To identify an infection, scientists kick-start Bartonella growth by putting a small ( 4 milliliter) blood sample into an insect growth medium called Bartonella alpha Proteobacteria Growth Medium that stimulates bacteria production. Within 10 days, there are enough bacteria present in the blood for a PCR test to yield an accurate diagnosis. Through a series of up to 40 temperature changes, PCR produces multiple copies of any bacteria DNA present, allowing scientists to definitively determine whether Bartonella is present.
The entire process – from petrie dish to verified results – takes between two to three weeks, said Galaxy’s Elam. Scientists can also run the test using non-blood bodily fluids or tissue samples.
Ed Breitschwerdt, internal medicine professor at N.C. State’s College of Veterinary Medicine, led the team that developed an analysis to more accurately diagnose Bartonella — cat scratch fever.
PHOTO CREDIT: ROGER W WINSTEAD – NCSU
Testing teams at Galaxy Diagnostics run PCR analyses on patient samples before inserting it into the insect growth medium in order to accurately gauge the bacteria’s growth. They also determine which Bartonella strain is present by running DNA sequence verification.
According to company data, the enhanced PCR analysis is four to five times more sensitive than the traditional PCR technique used to pinpoint the bacteria in the bloodstream, Elam said. With this extra sensitivity, Breitschwerdt estimated the tests will accurately diagnose between 80 percent to 90 percent of tested individuals who have Bartonella infections.
But identifying the pathogen is only part of the battle, he said.
“Our major contribution is that we’ve gone from thinking this bacterium only occurs in immuno-compromised patients or people with cat scratch disease to knowing there are quite a few people out there in specific populations who have this bacterium in their blood,” he said. “Now, we need research to find out what it means for patients to have this bacterium in their bloodstream.”
Proceeding with caution
Terry Yamauchi, M.D., an Arkansas Children’s Hospital pediatrician with infectious disease expertise, agreed with Breitschwerdt. While the insect growth medium-enhanced PCR is a valid method of identifying Bartonella, the analysis should not be a stand-alone clinical tool.
“The test itself seems to be scientifically very sound – growing more of the organism you’re searching for to improve test sensitivity will be helpful,” he said. “However, I worry about putting all our treatment-plan bets on this test because there’s little hard-core evidence indicating Bartonella is responsible for the chronic effects attributed to these infections.”
Until additional investigations into Bartonella yield a more definitive link between the bacteria and long-term symptoms, he said, physicians should opt to pair the test with traditional clinical observation and assessment.
WHAT IS BARTONELLA?
Bartonella, also called cat scratch fever, is a difficult-to-detect pathogen transmitted by blood-sucking insects, such as fleas, lice, or ticks. Individuals with frequent animal exposure, especially to cats, are also at high risk.
Many clinicians view Bartonella as a common culprit in chronic Lyme disease, arthritis, and multiple sclerosis-like neurological disorders, and is suspected to contribute to swollen lymph nodes, joint and muscle pain, inflammation, headaches, memory loss, and numbness in the hands and feet.
Once believed to only induce disease in animals, more recent research reveals this bacteria is also a threat to humans. According to the American Veterinary Medicine Association, nearly 60 percent of the 1,500 diseases recognized in humans can make the leap from animals to people. And, the phenomenon is growing. The Centers for Disease Control and Prevention estimates 70 percent of newly-identified human infections spring from animals.
To read the story at its Raleigh News & Observer location: http://www.newsobserver.com/2012/06/25/2151203/sharper-infection-detection.html#storylink=cpy
To read the story at its Charlotte Observer location: http://www.charlotteobserver.com/2012/06/24/3332959/sharper-infection-detection.html#storylink=misearch
Breakthrough of the Year
Published in the Spring 2012 Carolina Public Health Magazine
By Whitney L.J. Howell
Data Mining and Analytics in Radiology
Published on the May 23, 2012, DiagnosticImaging.com website
By Whitney L.J. Howell
Patient safety, satisfaction, and the quality of care you provide are no longer merely questions of how well you complete the appropriate services. More and more, group practices and hospital departments are turning to advanced analytics tools for data to streamline their work flow and improve efficiency. The list of tools is growing, as is the number of companies providing them, but according to industry experts, there are a few advanced analytics systems that should be your technology bedrock.
“It’s absolutely essential to have information at your fingertips if you’re going to provide the safest, most efficient care,” said Eliot Siegel, MD, diagnostic radiology and nuclear medicine professor and associate vice chairman for informatics at the University of Maryland. “Versions of analytics have existed in radiology systems, but they have given limited information. Now, we’re moving from monthly reports to having dashboards and virtually immediate feedback.”
However, it can be a challenge to implement advanced analytics effectively. The technology is changing so rapidly that it can be difficult to stay abreast of the latest developments, and convincing your colleagues of the tools’ benefits can be problematic. It’s important to remember, said David Hirschorn, MD, radiology informatics director at the Staten Island University Hospital, that advanced analytics offer something you don’t already have — data mining and evaluation that your PACS or RIS systems simply can’t do. Here are two major areas where advanced analytics are making a difference — and a glimpse of what’s to come.
Business Analytics
Equipment utilization: Having the latest or most up-to-date MRI or CT equipment is critical for your practice. But to get the most out of the machines, you must know to what degree you’re using them, said Hirschorn, also a radiology informatics researcher at Massachusetts General Hospital.
“You must ask yourself if you have too much or too little equipment to meet the demands of your department,” he said. “Is one machine being used a lot? Are patients waiting a long time? Either way, you could be losing business, so you have to find a way to quantify how your equipment is utilized to know if you’re making effective use of time.”
Implementing advanced analytics means you won’t have to wait until year’s end to determine your practice’s efficiency. For example, PowerScribe 360 Analytics from Nuance promises to help practices and departments analyze variance in radiologist reports, monitor ordering patterns, and use a variety of parameters to determine turnaround time.
“Why not bring analytics into real time. As you collect the data in real time, you can use it in real time,” Hirschorn said. “As radiology becomes more and more data driven, we need dashboards that might not provide day-to-day analysis, but week-to-week or month-to-month to identify our weak points.”
Personnel utilization: In addition to maximizing your equipment, it’s also helpful to monitor how efficiently you’re using your time, as well as that of your staff. For example, knowing the details of your neuroradiologists’ schedules can help determine if they have time to read less complicated scans, as well as brain MRIs.
“Analytics can tell you how busy your neuroradiologists or other subspecialists are. Are they really full or do they have time in between cases?” Hirschorn said. “Could you make utilization of that time?”
Merging or Blending Services: Deciding to merge facilities or share radiologists between locations can be a daunting task. Analytics can help institutions decide whether joining together would be viable or even financially advantageous. Software, such as advanced analytics solutions from Montage Healthcare Solutions, can provide data about how radiologists at various sites spend their time and how locations utilize their equipment, these tools allow decision-makers to have more well-informed conversations. Without this data, Hirschorn said, resolutions to merge resources are based on guesswork.
To read the remainder of the article at its original location: http://www.diagnosticimaging.com/informatics-pacs/content/article/113619/2075240
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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