Columbia U Electrical Engineer Professor Christine Fleming, 30
Images of the beating heart could make it easier to detect and treat heart disease.
Christine Fleming is trying to give cardiologists a powerful new tool: high-resolution movies of the living, beating heart, available in real time during cardiac procedures. Such technology might also one day help physicians pinpoint the source of dangerous irregular heart rhythms without invasive biopsies. It could even help monitor treatment.
Number of sudden cardiac deaths each year in the U.S.: 325,000
Her invention uses optical coherence tomography (OCT), a technique that captures three-dimensional images of biological tissue. A specialized catheter with a laser and small lens near its tip is threaded through the arteries. When the laser light reflects off the heart tissue, it is picked up and analyzed to create an image. OCT has a higher resolution than ultrasound and captures images faster than magneticresonance imaging, or MRI. But today OCT has limited cardiac application—usually to search the arteries for plaques. Fleming, an electrical engineer who joined the faculty at Columbia University this year, has designed a new type of catheter capable of imaging heart muscle.
One of the primary uses of the technology will be to locate, and monitor treatment for, irregular heart rhythms that are typically caused by disruption of the heart's regular tissue structure. In patients with arrhythmias, which can lead to heart failure, surgeons often burn away the affected tissue with targeted radio-frequency energy. Currently they perform the procedure somewhat blind, using their sense of touch to determine when they have come in contact with the muscle wall. "Since the physician doesn't have a view of the heart wall, sometimes the energy is not actually being delivered to the muscle," says Fleming, who adds that the procedure can last for hours. Fleming has shown in animal tests that her catheter, which uses a novel forward-facing lens, can successfully monitor the ablation in real time. Algorithms that help distinguish untreated from treated tissue offer further guidance. Abnormal orientation of cells
Abnormal orientation of cells in the heart wall is a clue to arrhythmias, which can be fatal. These images, created using optical coherence tomography, show the orientation of a rabbit's heart-muscle cells. Christine Fleming's approach to diagnosing arrhythmias could be an alternative to invasive biopsies.
Fleming is also developing algorithms to help improve the detection of arrhythmias by precisely measuring the three-dimensional organization of heart muscle. The technique works best when the tissue has been chemically treated to make it clearer, and thus easier to image. But her team at Columbia is now improving the algorithms so that the method works without this treatment. She hopes that in time the technology could supply an alternative to invasive biopsies, which are sometimes used to diagnose unexplained arrhythmias or to monitor heart health after transplants.
Fleming's arrival at Columbia earlier this year was something of a homecoming. As a high-school student in New York City, she interned at the NASA Goddard Institute for Space Studies, which is down the street from her current lab. But in the intervening years her engineering interests have increasingly become tied to medicine; her inspiration for studying the electrical properties of the heart came when she studied electrical engineering and computer science as an undergraduate at MIT. Working with physicians is especially exciting, she says, because "you get the sense that one day your technology will be used."
—Emily Singer- technologyreview.com
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How is a wind farm like a school of fish?
Caltech professor John Dabiri uses his engineering expertise to try to understand how animals move in their natural environments. While researching the swimming patterns of fish, he recently came to a surprising insight: the way we're thinking about wind power—specifically, the design of wind farms—is wrong.
Conventional wind farms are designed to minimize the turbulence caused by interactions between turbines. That creates an obvious problem, says Dabiri: "You space them out as far as possible. If you're talking about a wind turbine that has a 100-meter diameter, then you're talking about as much as a mile between wind turbines. That's a lot of space that could be used to generate electricity, but can't be because of these turbulent interactions."
Megawatts of wind-power capacity in the United States: 60,000
Dabiri thought of a solution while researching how fish form schools to minimize drag as they move about. "Fish can reduce the amount of energy that they use if they swim in certain coördinated arrangements as opposed to swimming alone," he explains. "In fact, fish in large schools form precise, repeating patterns that allow them to move most efficiently. There's some basic fluid-mechanics theory that you can use to explain why that might be the case. Jotting down the math for urban wind-turbine analysis, there was sort of a eureka moment where I realized that the equations were exactly the same equations that explain fish schooling.
"Why not use how fish form schools as a starting point for understanding how to design wind farms?" asks Dabiri. "We began to use the same tools that were used to determine the optimal configuration for fish schools to optimize the wind farm. We looked at an arrangement that's been identified as optimal for fish, and we found that if we, in our computer models, arranged our wind turbines exactly in the same kind of diamond pattern that fish form, you get significant benefits in the performance of a wind farm."
To maximize that performance, Dabiri would use vertical wind turbines, which have been around for years but are much less common than the familiar horizontal–axis turbines. Vertical turbines can perform better when they are packed together—at least if they are arranged in the optimal pattern Dabiri discovered. That raises the possibility of redesigning wind farms to increase the amount of power they produce and lower the cost. Dabiri says the turbines could be squeezed into existing wind farms so that they produce more power without taking up any more land. It's a solution that could greatly reduce the drag on an industry that often seems to be swimming upstream.
—Kevin Bullis- technologyreview.com--------------------------------
Growing up in Kenya, he strained to read by the dim light of a kerosene lantern. Now he’s making solar-charged lanterns and using them to spur economic development.
Evans Wadongo, 27
Kenya’s unreliable
electric grid doesn’t reach Chumvi, a village about two hours southeast
of Nairobi, where many of the 500 residents live in mud-walled,
grass-roofed homes and eke out a living raising goats and growing kale,
maize, and other crops. Yet an economic transformation is taking place,
driven by an unlikely source—solar-charged LED lanterns. It can be
traced to the vision of Evans Wadongo, 27, who grew up in a village much
like this one.
As a child, Wadongo struggled to study by the dim, smoky light of a kerosene lantern that he shared with his four older brothers. His eyes were irritated, and he often was unable to finish his homework. “Many students fail to complete their education and remain poor partly because they don’t have good light,” says Wadongo, who speaks slowly and softly.
In Chumvi, Kenya, Irene Peter helps her son with English homework by LED
light, which is cleaner and less expensive than kerosene.
 |
| Each lamp is stamped “Mwanga Bora,” which means “Good Light” in Swahili. |
The transformation in Chumvi began two years ago, when a woman named Eunice Muthengi, who had grown up there and went on to study in the United States, bought 30 lanterns and donated them to women in the village. Given that the fuel for one $6 kerosene lamp can cost $1 a week, the donation not only gave people in the town a better, cleaner light source but freed up more than $1,500 a year. With this money, local women launched a village microlending service and built businesses making bead crafts and handbags. “We’re now able to save 10 to 20 shillings [11 to 23 cents] a day, and in a month that amounts to something worthwhile,” says Irene Peter, a 43-year-old mother of two who raises maize and tomatoes. “Personally, I saved and got a sheep who has now given birth.” She also got started in a business making ornaments and curios.
Christine Mbithi, a mother of four in Chumvi, chops spinach by LED lamplight.
Wadongo is also changing lives with the manufacturing jobs he is creating. In an industrial area of Nairobi, banging and clanking sounds fill a dirt-floored shack as two men hammer orange and green scraps of sheet metal into the bases of the next batch of lamps (soon to be spray-painted silver). Each base is also stamped with the name of the lamp—Mwanga Bora (Swahili for “Good Light”). The three men in the workshop can make 100 lamp housings a week and are paid $4 for each one. Subtracting rent for the manufacturing space, each man clears $110 per week—far above the Kenyan minimum wage.
Some of the lamps are completed in the kitchen of a rented house in Nairobi. Three LED elements are pushed through a cardboard tube so they stand up inside the lantern’s glass shade. The LED elements, photovoltaic panel, and batteries are sourced from major electronics companies. Overall, the devices are rugged; the steel in the housing of the lantern is a heavy gauge. If a housing breaks, it can be serviced locally—and the electronic parts are easily swapped out.
Wadongo now heads Sustainable Development for All, the NGO that gave him his leadership training, and he is focusing it on expanding the lamp production program. It has made and distributed 32,000 lamps and is poised to increase that number dramatically by opening 20 manufacturing centers in Kenya and Malawi. Wadongo says that teams in those centers will independently manufacture not only the lamps but “any creative thing they want to make.”
—David Talbot- technologyreview.com
The mPedigree Network, based in Ghana, lets people determine with a text message whether their medicine is legitimate.
Activist and Astrophysicist Bright Simons, 31
"I grew up in Ghana, where we'd inherited the British boarding school system. At Presbyterian Boys High School, many upperclassmen were abusive toward the younger students. Once, I was made to stay awake all night in a kneeling position outside. But in my final year at school I became student council president and led efforts to reduce abuses. That experience opened my eyes to a whole new world of fighting the system—of being an activist. And this led directly to my becoming a technology innovator.
A few years later, after studying astrophysics at Durham University in the U.K., I transferred that instinct to try to help African farmers. They grow food organically by default, because they don't have money for chemicals. But they also don't have money for the organic certification process that would let them get better prices. So in 2005, I led a team of PhD students to try to implement a solution using mobile technology.
Percentage of medicine sold in some countries is bogus: 30
The idea was that at the point of sale there'd be a code on the product. You'd enter that in a mobile device, and up will pop the history and even pictures of the farm. But we realized a big flaw: farmers have to be trained to do the coding. This was not practical.
But picking up a fruit and wanting to know if it is organically grown is similar to picking up a pack of medicine and seeing if it was properly tested and certified. About 2,000 people die every day from counterfeit medicine. So we shifted the idea to pharmaceuticals.
In 2007 we set up a nonprofit organization in Ghana and rolled out a pilot, and the next year Nigerian health officials invited us to replicate the concept there. But we wanted to get to a point where a big company like Sanofi-Aventis would use us. We learned that most companies won't do business with an NGO, so in 2009 we launched mPedigree as a business.
You can send a free text message and get a reply in a few seconds verifying [that a medicine] is authentic. In addition, distributors and other middlemen can check the codes to verify that the supply has not been compromised. This helped reveal to a major Indian company that there was pilfering at a depot. Genuine antimalarial medicines would be replaced by counterfeits. The shady characters cannot get away with this anymore. If we had not stopped these leakages in the supply chain, they could have put thousands of patients at risk.
The system is used in Ghana, Nigeria, Kenya, and India, with pilots in Uganda, Tanzania, South Africa, and Bangladesh. We've got a relationship with many of the major regional—and a growing number of multinational—pharmas, including Sanofi-Aventis. In Nigeria our codes are on 50 million packs of antimalarial drugs alone, and we have just signed up two Chinese drug makers.
We are now expanding to seeds, cosmetics, and other businesses. And new applications are emerging that we hadn't expected, in the areas of logistics, supply chain management, and marketing. If you send an SMS to check authenticity, you've also given good information about exactly where and when a drug was sold—as well as provided a potential marketing opportunity to dispense coupons. We have built a major platform for supply chains in the developing world. But back at my school, of course, they still remember me as the activist."
—as told to David Talbot- technologyreview.com
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