PeoPle, life, etc...
THE MORUNG EXPRESS
An ancient toy could help improve healthcare in the developing world Ed Yong
n 2013, on a visit to a Ugandan clinic, Manu Prakash noticed a small metal machine propping open a door. It was a centrifuge—a device that spins tubes of liquid at extremely high speeds, so that any particles within them sink to the bottom. This process is used to separate out everything from cells to viruses to DNA, which means that centrifuges underpin a lot of modern science. They’re as essential to hospitals and laboratories as saucepans are to kitchens. But centrifuges run on electricity, which is why many clinics in the developing world can’t use them, even if they can afford them. That’s why the one that Prakash visited had repurposed their centrifuge as a doorstop. It’s also why the clinic couldn’t carry out a lot of simple diagnostic tests. “On a chart, they listed all the tests that they do, but they were only really doing two out of 10,” recalls Prakash. “The other eight required centrifugation. I’ve seen this play out over and over again. It was clear that we needed a centrifuge that could operate without electric power.” Prakash has now created one. Modeled on an ancient children’s toy, and made with little more than paper, string, and tape, it can spin at speeds of up to 125,000 revolutions per minute (rpm). That’s more than enough to, say, separate cells or malaria parasites from blood samples. And it’s actually much faster than a lot of desktop centrifuges, even though Prakash’s device is entirely hand-powered, weighs less than 2 grams, and can be made for just 20 cents. He calls it the paperfuge. “This type of innovation has the potential to support the creation of cost-appropriate, rapid, and robust diagnostics that can be administered by local health care workers in the lowest-resource communities in the world,” says Carol Dahl, Executive Director of the Lemelson Foundation. Prakash, a biophysicist who grew up in India and now works at Stanford University, has a habit of creating devices like this. Last year, I wrote about his Foldscope—a $1 pocket microscope that can be folded from a sheet of paper. He has also developed a skin patch that detects parasitic worms in the manner of an ultrasound, but for less than $10. He has been working on tools for extracting malarial parasites from mosqui-
to bites, and computers that run on water droplets. For these feats, he was awarded a MacArthur “genius grant” last year—a coveted $625,000 award given to exceptional and innovative people. Having decided to make a cheap centrifuge, Saad Bhamla and other members of Prakash’s team started thinking about simple spinning devices. Yo-yos were an obvious pick, and one of the lab members was adept with them, having once been a circus performer. But the group soon learned that yo-yos can only achieve about 4,000 rpm. At such low speeds, it would take far too long to spin down a typical laboratory sample. The same problem has plagued other attempts to build hand-powered centrifuges out of egg-beaters or salad-spinners—they just don’t spin quickly enough.
stood and its fundamental limits were completely unknown. So we spent six months thinking about the math, all with the goal of asking how fast it could really go.” By playing around with the disc size, the position of the holes, the strings, and the speed at which the users pull them apart, the team managed to hit 125,000 rpm. That’s “the fastest rotational speed every recorded for a human-powered device,” they wrote. “We have submitted an application to Guinness World Records. But anyone can make a whirligig to our specifications and get those numbers. It’s just physics; it’s not special materials.” In the actual paperfuges, the discs are just stiff, waterproof paper, like the stuff that bank notes are made from. The strings are just fishing lines, tied to two wooden handles for easy winding. Each paperfuge has
‘Zero-waste’ living is possible
Don't rush to judgement, these four true tales teach us couple of years ago, a friend accused me of being really slow on the uptake, so I called him last night. "Yep," I said. One should always take time over important issues instead of rushing to judgement. Case in point: A recent news report says police were shocked to see the driver of a forklift truck use her vehicle's pointy bits to pick up and move a van that someone had parked in front of her house. It was a cheeky, dangerous act, so police detained the driver and then set out to trace the van owner. It turned out to be the forklift driver. "Villain and victim were the same person," said reader Sarath Malhotra, who forwarded me the link to the news story from the US state of Wyoming. Police realised they now lacked a victim to file a complaint and so had to prosecute the motorist for Wearing Flipflops While Operating a Forklift, which is apparently an actual offence. (It is clear to me that law-makers worldwide work in three separate divisions: Criminal Law, Civil Legislation and Silly Laws, the third group being by far the most prolific.) Anyway, the tale presaged the arrival in my inbox of a rash of news reports with unexpected twists. An email from a regular contributor reported a recent incident in the UK town of Wiltshire. A woman saw a man with some sort of long-bladed weapon lurking menacingly in a quiet street. She called police and nine squad cars full of officers turned up -- to find a man trimming a hedge. The conversation went something like this. "What are you doing?" "Trimming my hedge, then having a cup of tea and a nap." "No mass murders or terrorist activities?" "I don't think so but I'll check my diary." Next came a news item from the Washington Post. An old, homeless bag lady had long the habit of making deranged-sounding claims that the government owed her $100,000. Eventually a kindly social worker took the trouble to read through the paperwork in one of the woman's bags -- and discovered that the government owed the woman, 80-year-old Wanda Witter, $100,000. Be nice to homeless people, who may well have more disposable income than we do. The fourth tale-with-a-twist came from a reader who collects "dumb criminal" reports. In California, a fugitive female, 29, found a pair of handcuffs at a friend's house and made a snap decision to try them on. Click! Now where's the key? No key! Unable to remove them, she called the police for help. They turned up at the house and were delighted to find a woman they had been looking for, pre-cuffed and ready to go. This was kind of like a Christmas present for police detectives, who usually have to do all their own detecting and handcuffing. So there we go. Don't make rush decisions. Yet there are exceptions. I told my children that I will love them unconditionally whatever they do, even if they rob banks or start wars, but if they ever use the words "craycray", "whatevs" or "swag" I kick them out and change the locks right now. That's reasonable, right?
“So, I asked the [team] to bring more toys into the lab,” Prakash says. And someone brought in a button spinner. The simple toy, also known as a buzzer, is part of the whirligig family, and has been around for more than 5,000 years. They’re made by passing strings through the center of small discs—everything from buttons to bones and flattened musket balls. By twirling the ends of the strings, you spin the disc and wind the strings together. If you now pull the strings outwards, they unwind and rapidly spin the disc in the opposite direction. By filming a basic whirligig, Prakash’s team were astonished to find that it could spin at 10,000 rpm. “We realized that this is a toy that no one had thought about,” he says. “The physics of how it works weren’t under-
two discs, which are stuck together by bits of Velcro and sandwich two sealed drinking straws. If you want to spin some liquid, you inject it into thin plastic tubes and load these into the straws. Stick the discs together, wind up the device—and off you go. In less than 2 minutes of spinning, the paperfuge can separate the liquid part of blood (plasma) from the cells within it—an essential step in many diagnostic tests. In 15 minutes, it can isolate malaria parasites from a finger prick’s worth of blood. And despite its simple nature, it has a number of seals, plugs, and other safety features, designed to stop users from spraying themselves with blood and other fluids. “We’ve built a thousand of these, taken a hundred into the field, and aggressively tested them,” says Prakash. “We’ve even tried throwing them into the street to see if any samples leaked out.” “It’s so simple and yet so clever,” says Andres Martinez from California Polytechnic State University, who also works on cheap diagnostic tools. “Beyond the potential applications of the [paperfuge], I think it will inspire others to think about how other simple technologies could be applied toward improving life in developing areas of the world.” “The importance of sample preparation is often overlooked and under-estimated. Yet it is the wheels of a car, without which a diagnostic test will not go far,” adds Helen Lee from the University of Cambridge. If the paperfuge can be integrated directly with tests that only require a few drops of blood, “it would be a great addition to the diagnostic tool box in resource-limited settings.” The team is now testing other materials. By switching from paper to certain plastics, they could use 3-D printers to mass-manufacture millions of paperfuges; they could also print discs with more complicated liquid-holding channels, for carrying out more sophisticated chemical reactions. Or, by using transparent plastic discs, they could create paperfuges that could double as microscope slides, and be examined immediately after being spun. They have also taken their paperfuges to rural Madagascar to see if health workers can actually use them in the field. “The first time you explain it, people look at you speculatively,” he says. “But when you take it out and demonstrate it, it’s almost like a lightbulb goes on—ironic, since these are places that have no electricity.”
hen we require something, it is natural to turn to others for help. And guess what Mridula Ramesh, the Joint Managing Director of Southern Roadways, is asking for. She wants “waste”! “It is one of the most wonderful resources we have,” she says. In the last 18 months, Mridula has moved towards an almost ideal situation. She has drastically reduced the generation of waste where she lives and works. As a result, she is practically running short of waste to put into her compost bins. This has prompted her to request for food waste from restaurants, departmental stores and vegetable markets in her vicinity. Hers is perhaps the first and only family in Madurai that does not send its trash out any more. “Waste affects our health and the more waste we generate and strain our landfills, it contaminates the soil and water and impacts the environment too,” she reminds. “We cannot reverse the devastating impacts of climate change but at least adapt ourselves to somewhat halt it. And this can be achieved by understanding the critical link between climate change and waste,” she adds. If waste is the secret weapon to fight climate change, the know-how to reduce its generation or reuse it, is crucial. And this is the message Mridula Ramesh is bent upon spreading now. She got working on it when the bore well inside her sprawling bungalow in Chokkikulam in Madurai went dry four years ago and she had to purchase water from private tankers. “I had been reading a lot about climate change over the years. With taps going dry at home, I realised it was time for individual action. To be a part of the solution was inevitable and imperative now,” says the young member of the iconic TVS family. The connection between waste and floods, waste and mosquitoes, waste and stray animals only underlined how waste is important in fighting climate change and she immediately decided to look at two things – her personal consumption and waste production pattern. “It had to begin at home and we decided to be honest enough to look at our ugly selves in the mirror and address the issue. It meant measuring our
mistakes,” she asserts. For a week in July 2015, her small family of four and the staff observed the amount of waste they were collectively throwing into the municipal bin. Inclusive of 11 kilos of garden waste, it averaged 17.6 kilos a day! And Mridula was shocked to find herself as the biggest culprit of unmindful and irregular grocery purchase. “I don’t cook and yet I was cluttering my shelves with stuff that caught my attention in the market and forgot to use them. And all that was becoming waste.” She instantly set herself a target – “to go zero-waste at home.” Displaying the data of what we bought, the quantity of food cooked, eaten and thrown, hit everybody hard, says Mridula. A “name and shame” board was put up on the wall for everybody to see. “Now I strictly stick to a shopping list fully aware of the kitchen requirement and the stocks and our grocery bills have dropped by 15 percent,” she points out. Each item purchased is now kept at eye level and in transparent jars on the kitchen shelves and inside the fridge for easy access and timely consumption. The next step was segregating kitchen waste. Much of the kitchen and garden waste that is sent to landfills can be turned into an energy source or fertiliser, says Mridula, who rues the unwillingness of the people to segregate waste.
To make it simple and uncomplicated, she placed separate, big and open bins for biodegradable and non-biodegradable waste in a way so that the girls in her kitchen did not have to move even a step to throw the waste in the right bin. “If things are easy and hassle-free, everybody will be inclined to join in a good cause,” she notes. Mridula’s graduation major in microbiology from Cornell University came in handy as she took to composting through trials and errors using aerobic and anaerobic processes. From the suitable size of composters to which bacteria can give the most viable compost under what temperature conditions and period of time, Mridula gradually worked on a complete package. Though her experiments are still on, Mridula says she wants to give people an easy solution for the best results. The various types of manure she created in her backyard yielded her a flourishing vegetable, fruits and flowering garden in no time. So much so that she is now inspired to market and sell the compost. The best part about Mridula’s approach is she is a voracious reader of articles related to climate change, experiments in her house before demonstrating the success, tracks daily progress with good quality and measurable data, uses small teams to involve everybody and makes them ac-
countable and answerable. “In order to sustain what you have started, the system has to run on its own steam, be easy enough with no friction on the path and there has to be a payback,” she believes. The outgoing waste from her bungalow today is roughly about 400g. Mostly FMCG packaging material, it is sold to the junk dealer. So there is an economic gain out of waste as well but how the non-biodegradable waste can be further managed continues to worry her. What satisfies her though is the transfer of the same waste reduction model to her company with an employee strength of 500-plus that generated 200 kg of waste till last year. Within five months, the canteen waste has reduced to less than 10 kilos from 40, the grocery bills are less and the entire garden waste of 110 kg is going for bulk composting and anaerobic management for production of gas. “We just need to pretend that we do not have a garbage service,” says Mridula, “and then see how our choices and lifestyle will change!” Time for energy revolution A small solar energy playroom has been set up for the children. Water and power consumption pattern is monitored to minimise usage. A biogas plant has been installed to use the gas, produced out of waste, in the kitchen for cooking. Mridula Ramesh’s zero-waste lifestyle is distinguished by the fact that she combines her eco-friendly actions with teaching in business schools on climate change and entrepreneurship and also writing on environment. She is in the process of wrapping up a book on climate change. The businesswoman that she is, Mridula also doubles up as a clean tech investor having invested in five clean technology start-ups. “NGOs raising awareness about damage to the environment is not enough. It is the start-ups that create a wonderful impact,” she believes. The Sundaram Climate Institute that she has set up in Madurai offers waste reduction programmes to students and residents through age-appropriate teaching modules, talks and video screening and encourages innovative ideas and entrepreneurship in clean technology.
Readers may please note that the contents of the articles, letters and opinions published do not reflect the outlook of this paper nor of the Editor in any form.