Midday meals for schoolchildren in India: More good than harm

On July 16th at least 23 children in the Indian state of Bihar died after eating a midday meal that was provided for free by their school. Nearly as many are in critical condition in a local hospital. Tests have revealed that adulterated cooking oil, perhaps containing pesticides, is likely to blame. A government inquiry has determined that the principal of the school, who is in hiding, must be held responsible for the bad ingredients or unsafe methods used in preparing these meals.

This event is horrific, without a doubt. Yet its damage could be even worse, if it raises too many doubts about the value of a largely successful programme. The midday-meal scheme, which began on a small scale decades earlier, received the support of India’s Supreme Court in 2001. Since then most Indian states have adopted it, offering free meals to children in state-run or state-assisted schools. More than 120m children, including many who would otherwise go hungry, receive these meals every school day.

According to a recent analysis by Farzana Afridi of Syracuse University and the Delhi School of Economics, at a cost of three cents per child per school day, the scheme “reduced the daily protein deficiency of a primary-school student by 100%, the calorie deficiency by almost 30% and the daily iron deficiency by nearly 10%.” Ms Afridi also found that, after controlling for all other factors, the meals scheme has boosted the school attendance of girls by 12%. Abhijeet Singh of Oxford University found that, in some parts of India where children were born during a drought, the health of those who had been brought into the meals scheme before the age of six was compensated for earlier nutritional deficits.

What the disaster in Bihar has done, at the very least, is to highlight some of the pitfalls of the scheme. As with any programme of this size in a country rife with corruption, the meals scheme is riddled with problems. The corruptible state is not alone in funding the programme; it is joined by private companies and NGOs. Corruption exists not just among state entities but among the supporting agencies too, as was demonstrated in 2006 when a Delhi NGO was caught dipping into rice that was meant for midday meals. In the states of Bihar and Uttar Pradesh, where the levels of malnutrition are among the highest in the country, it was found that only three-fourths of the food meant for children reached them. Food is often stolen by the administrators’ faking their students’ attendance. Beyond that, reports of adulteration—not only with shoddy or unsafe foodstuffs, but including finding worms, lizards and snakes—are common.

Next month, the Indian government will be voting on a food security bill which aims to provide food to 60% of the entire population, by means of a public distribution system. This one school’s tragedy comes at an especially crucial moment, when officials ought to be forced to inspect the leaky pipeline of distribution. At the same time it will be important to bear in mind: This scheme has done a lot more good than harm.

First published on economist.com.

Image credit: GlobalPartnership for Education

To kill, cheetahs use agility and acceleration not top speed

Researchers have used gadget-laden collars to record cheetahs’ movements in the wild. They found that cheetahs succeed not because it is the fastest animal on land, but because of its incredible acceleration and unmatched turning speeds.

Most of what we know about cheetahs in the wild is based on direct observation, or through videos from remote cameras. This limits our understanding of cheetahs to open habitats and daytime. Alan Wilson at the University of London’s Royal Veterinary College wanted to study cheetahs better.

Over the past ten years, Wilson and his team have been perfecting devices to study the locomotion of animals. For cheetahs, they assembled a collar that carries a GPS to record location data, an accelerometer to measure speed, a gyroscope to understand angular motion, and a magnetometer to make location data more accurate, which it does by measuring tiny changes in Earth’s magnetic field. The data were transmitted back to the researchers in real time through radio.

“The key development,” Wilson said, “was to pack all that in a low-power device”. The collar relies only on solar cells for recharging, but carries a battery in case of failure.

After tracking 367 runs by five cheetahs in the wild, Wilson found many surprising results.

First, the top speed of most cheetah hunts is on average half the “record speed”. That record speed is 102 km per hour, and was noted in 1965 (though not published until 1997), by a veterinary surgeon in Kenya.

The average length of a cheetah’s hunt was about 180 meters. Instead, on average, cheetahs covered about six kilometers every day. With only two hunts made every three days, high speed runs make for only a tiny fraction of a cheetah’s daily routine.

Second, he found that cheetahs can successfully hunt in all terrains, not just open fields. The run data were overlaid on Google Earth to visualise the landscape the cheetahs were operating in. This showed that only 20% of chases in open fields were successful, compared to 31% in dense cover. Wilson thinks that dense cover, such as trees, might give cheetahs vantage points that open fields cannot.

Third, cheetahs can decelerate faster than they can accelerate, much as sports cars with powerful engines need beefed-up brakes. While both these processes require different sets of muscles and depend on different conditions, the rates of acceleration and deceleration beat those of any other land-dwelling animal. Based on the recorded data, Wilson calculates that the muscle power output of cheetahs is about four times that of Usain Bolt, three times that of polo horses, and nearly double that of greyhounds.

The top speed of a cheetah hunt had no correlation to the successful outcome of the hunt. Instead, Wilson found that success depended more on how fast the cheetah could slow down, rather than on how fast it could speed up. It is this last phase of a hunt that was critical for success, where the cheetah slows down. When these two observations are put together, Wilson thinks that it seems cheetahs don’t abandon hunts early to save energy or reduce risk of injury.

Finally, cheetahs are not built to be able to turn at their highest speed. In an artificial setting, which astronauts and fighter pilots are put into for training, the force felt by a cheetah trying to turn around at top speed could knock it unconscious. Instead they use their ability to slow down and their ridged footpads and claws to grip the ground well enough to turn quickly.

The results of Wilson’s work are published in the journal Nature today. Craig McGowan at the University of Idaho, an expert in understanding animal locomotion who was not involved in this, was impressed by Wilson’s work. “This research has been able to collect a huge amount of data from animals behaving naturally in their environment. No other dataset of this kind exists,” he said.

Roger Kram at the University of Colorado, Boulder, another biomechanics expert who was not involved in the study, said, “The technology used is absolutely fantastic. Most people studying biomechanics of running do so in labs. I’d like to see this technology applied to prey, such as impala and Thomson’s gazelle.”

Wilson is keen to see the technology used widely. “My aim is not to commercialise this. We’ve revealed all the technology and methods in our paper,” he said. His team has already started using it on lions and wild dogs.The Conversation

First published on The Conversation.

Image credit: photosbyflick

This story made it to the front page of Reddit and Digg, receiving over 130,000 views in two days.

Social entrepreneurs in India: Water for all

Nearly three-fourths of all diseases caused in India are due to water contaminants. Despite that, one in eight Indians still lacks access to clean drinking water. The poor now realise that paying for clean water can save much more in health-care costs later. It was this market that Sarvajal, a social enterprise in India, wanted to cater to.

Founded in 2008, Sarvajal—which in Sanskrit means “water for all”—now sells clean drinking water to more than 70,000 people in rural India. In bigger villages, it employs local people to man filtration plants and sell water. In small villages it installs solar-powered water dispensing machines (pictured) that use prepaid (or pay-as-you-go) smart cards that can be topped up just like a mobile phone. The machines send data to a central server via SMS, which helps Sarvajal ensure regular supply of clean water.

Sarvajal started with some help from the Piramal Foundation, a charity. And it is not alone: Water Health International was launched with an investment from the Acumen Fund and the Naandi Foundation’s not-for-profit company was backed by a charity with the same name. What sets Sarvajal apart is that it has stayed away from government subsidies while still keeping the price of water low. It sells 10 litres of water for four pence (or six cents), just as much or lower than its competitors.

“Subsidies are not a long-term solution,” says Anand Shah, Savajal’s founder, who grew up in America and moved to India to become a social entrepreneur. It took a healthy bit of tinkering to lower the price of installation and maintenance for its water supply infrastructure. It costs on average $2,500 to install a filtration plant, which is about half the expense of similar projects. Sarvajal claims to recover those costs within three years.

Setting up its project was not easy. Savajal needed to deal with things that few businesses in rich countries have to worry about: lack of proper roads in villages, irregularity of power supply, unreliability of water sources and devising a system of money transfer. Having reached a respectable size, Mr Shah is hopeful that scaling up his business further will be less challenging.

Apart from villages, Sarvajal’s other obvious market is the urban poor. Nearly 100m people live in very densely populated slums in India’s cities. They are more willing to pay a higher price for water than villagers who have a much smaller disposable income. But Mr Shah says that “water barons”, sellers of bottled-water, have been trying to block Sarvajal’s entry into cities. After many months of efforts, this time not without help from the government, Sarvajal will soon be launching its first filtration plant in Delhi.

First published on economist.com.

Image credit: Sarvajal

Marine biology: Flea market

A newly discovered virus may be the most abundant organism on the planet

What is the commonest living thing on Earth? Until now, those in the know would probably have answered Pelagibacter ubique, the most successful member of a group of bacteria, called SAR11, that jointly constitute about a third of the single-celled organisms in the ocean. But this is not P. ubique’s only claim to fame, for unlike almost every other known cellular creature, it and its relatives have seemed to be untroubled by viruses.

As Jonathan Swift put it in a much-misquoted poem, “So, naturalists observe, a flea/Hath smaller fleas that on him prey”. Parasites, in other words, are everywhere. They are also, usually, more abundant than their hosts. An astute observer might therefore have suspected that the actual most-common species on Earth would be a “flea” that parasitised P. ubique, rather than the bacterium itself. The absence of such fleas (in the form of viruses called bacteriophages, that attack bacteria) has puzzled virologists since 1990, when the SAR11 group was identified. Some thought the advantage this absence conferred explained the group’s abundance. But no. As they report in this week’s Nature, Stephen Giovannoni of Oregon State University and his colleagues have discovered the elusive phages. Swift’s wisdom, it seems, still holds good.

Tracking down a particular virus in the ocean makes finding a needle in a haystack look a trivial task. A litre of seawater has billions of viruses in it. Modern genetic techniques can obtain DNA sequences from these viruses, but that cannot tie a particular virus to a particular host.

To do so, Dr Giovannoni (pictured) borrowed a technique from homeopathy: he diluted some seawater to such an extent that, statistically speaking, he expected a 100-microlitre-sized aliquot to contain only one or two viruses. The difference between his approach and a homeopath’s was that what homeopathy dilutes almost to nothing are chemicals, and thus cannot breed. A virus can, given a suitable host. So he mixed each of several hundred aliquots into tubes of water containing P. ubique. Then he waited.

The race is to the Swift

After 60 hours, he looked to see what had happened. In most cases the bacteria had thrived. In a few, though, they had been killed by what looked like viral infection. It was these samples that he ran through the DNA-sequencing machine, in the knowledge that the only viral DNA present would be from whatever it was had killed the bacteria.

His reward was to find not one, but four viruses that parasitise P. ubique. He then compared their DNA with databases of DNA found in seawater from around the world, to find out how abundant each is. The upshot was that a virus dubbed HTVC010P was the commonest. It thus displaces its host as the likely winner of the most-common-living-thing prize.

That does depend, of course, on your definition of “living thing”. Some biologists count viruses as organisms. Some do not. The reason is that a virus relies for its growth and reproduction on the metabolic processes of the cell it infects. This means viruses themselves are hard to parasitise, since they do no work on which another organism can free-ride. Which is why the next two lines of Swift’s poem, “And these have smaller fleas to bite ’em/And so proceed ad infinitum”, are wrong—and why, because HTVC010P itself can have no parasites, it probably really is the commonest organism on the planet.

First published in The Economist.  Also available in audio here.

References:

  1. Zhao et al., Abundant SAR11 viruses in the ocean, Nature2013.
  2. Brown et al., Global biogeography of SAR11 marine bacteria, Mol Syst Biol2012.
  3. Swift, Poetry: A Rhapsody, 1733.

Image credit: Lynn Ketchum

Drug development: Teaching old pills new tricks

Exploding research costs and falling sales: there seems to be no cure for the pharma industry’s two big afflictions. But it may have found a way to both cut costs and open up new markets: repurposing drugs already approved for treatment of one disease or those that failed to gain approval in the late stages of development. Alas, this is not as easy as it sounds—mostly for legal reasons.

Finding new uses for old or failed drugs is on average 40% cheaper than inventing a new drug from scratch: it allows to skip the early stages of development. Since coming up with a new drug can cost more than $1 billion, such savings are nothing to sneeze at. Repurposing also trims the risk of failure because new drugs hit a dead end mostly during the early stages of development.

In 2007, a report in Nature, a science journal, counted 41 drugs that have found new uses. But there should be many more, experts say. This is why America’s National Institutes of Health, the country’s biggest government agency financing drug research, and the Medical Research Council, its British counterpart, each have launched new grant programmes. Worth $20m and £10m ($15m) respectively, they are meant to allow university researchers analyse failed drugs from big pharma firms such as Pfizer, AstraZeneca and Eli Lilly and see whether they can be repurposed.

Yet such schemes are not enough, as work by Grant Churchill, a researcher at Oxford University, shows. In a recent paper in Nature Communications, another science journal, he describes how he and his colleagues looked for a drug to treat bipolar disorder, which causes uncontrollable mood swings. Instead of developing a new compound, they tested a library of known ones and found that ebselen, a drug first developed to treat stroke, was a candidate. Their claim, based on animal tests, is that ebselen is as good as and much safer than lithium, currently considered the best treatment for bipolar disorder.

But this was where things hit a hurdle that is hard to overcome. Universities do not have the money to further develop promising drug candidates that need to be tested on a large scale. Expensive human trials are usually carried out by pharma firms, which own the patent for a drug and thus can hope to make their money back. But in the case of many repurposed drugs, like ebselen, the patent has expired. Filing for a new one, which is possible, is not of much help: patients could simply buy versions of the drug which are already available from other makers.

One way of solving this problem would be to change the patent system, for instance by extending the length of patent protection, but this could hamper innovation in other ways. A better solution, argues Benjamin Roin, a law professor at Harvard University, is to have regulators grant the drugmaker that has repurposed the drug some exclusivity and thus time to recover research costs: it is rare that a drug is used in the same form and the same dosage for two different diseases; regulators could wait a few years before they allow other firms to offer the drug for the new purpose. If old drugs can learn new tricks, regulators should do so, too.

First published on economist.com.

References:

  1. Singh et al., A safe lithium mimetic for bipolar disorder, Nature Communications2013.
  2. DiMasi et al., The price of innovation: new estimates of drug development costs, Journal of Health Education2003.
  3. Chong & Sullivan, New uses for old drugs, Nature2007.
  4. Roin, Unpatentable Drugs and the Standards of Patentability, Texas Law Review2009.

Image credit: The Economist

Cancer drugs: Refusing to die

Suicide is a part of life. Whenever any of the 100 trillion or so cells that make up the human body malfunction, which happens all the time even in healthy tissue, they are programmed to provoke their own death. The mechanism hinges on a protein called TRAIL, which is produced by the damaged cell and binds to receptors on its surface, causing inflammation. That is a signal for the immune system to sweep in and, through a process called apoptosis, break down the damaged cell and recycle its parts to feed healthy ones. If this self-destruct is subverted, however, the result is a tumour.

When TRAIL’s tumour-suppressing ability was first discovered in 1995 researchers hoped that by discriminating between cancer cells and healthy ones, TRAIL would do away with the debilitating side-effects associated with traditional treatments like radio- and chemotherapy. These are good at destroying tumours but also cause lots of collateral damage. Unfortunately, it turned out that simply injecting a synthetic version of the molecule into the patient’s body provoked only a limited immune response in a handful of cancers.

That, says Joshua Allen from the Pennsylvania State Cancer Institute, was because people assumed that cancer’s subversion of TRAIL consisted merely in halting the molecule’s production within the cell. It turns out, however, that cancerous cells also suppress their TRAIL receptors, so no amount of synthetic TRAIL sloshing about would ever be enough. What you need, Dr Allen reasoned, is something to reboot the TRAIL-producing pathway within cells as well as to unblock their TRAIL receptors. Only then would the immune system be spurred into action.

So he and his colleagues sifted through a library of molecules maintained by America’s National Cancer Institute and found a molecule, called TIC10, whose biochemistry seemed to fit the bill. When enough of these molecules accumulate in a cancer cell, they activate a protein called FOXO3a. This binds to DNA and flips on many biological pathways, including those involved in the TRAIL mechanism that lead to the immune-system alerting inflammation.

As Dr Allen and his colleagues report in Science Translational Medicine, tests in mice with brain tumours confirmed the biochemical hunch. Murine subject given TIC10 lived twice as long as those that received no treatment. The drug also worked for lymphoma, as well as breast, colon and lung cancers. And it did not seem to cause the wasting side-effects typically associated with chemotherapy, suggesting that it can indeed tell cancer cells from healthy ones. As an added bonus, TIC10 is small compared to TRAIL, and cheaper to concoct than the complex protein is.

Last year Dr Allen secured a $1.3m grant from Pennsylvania’s department of health to begin clinical trials. These will be carried out in collaboration with Oncoceutics, a drug company. Nine out of ten promising molecules which work in mice fail in humans, so “Cure for cancer” headlines must wait. If TIC10 does live up to its promise, though, it would make one killer app.

First published on economist.com.

Image from here

A revolution in lens-making

Understanding of optics has changed no end since the world’s oldest known lens was ground nearly 3,000 years ago in modern-day Iraq. Yet its Assyrian maker would instantly recognise today’s lenses, which continue to be made much as they were then: by fashioning a piece of transparent material into a solid with curved surfaces. Just as invariably, the curves introduce optical aberrations whose correction requires tweaking the lens’s geometry in complicated ways. As a consequence, lenses remain bulky, especially by the standards of modern electronics.

Enter Federico Capasso, of Harvard University. He and his colleagues have created a lens that is completely flat and the width of two human hairs. It works because its features, measured in nanometres (billionths of a metre), make it a “metamaterial”, endowed with some weird and useful properties.

According to the laws of quantum mechanics, a particle of light, called a photon, can take literally any possible path between source A and point B. However, those same laws stipulate that the path of least time is the most likely. When a photon is travelling through a uniform medium, like a vacuum, that amounts to a straight line. But although its speed in a vacuum is constant, light travels at different (lower) speeds in different media. For example, it moves more slowly in glass than it does in air. So in a medium composed of both air and glass, light’s most likely path from A to B will depend on the thickness of glass it needs to traverse, as well as the total distance it needs to cover. That means that the light may sometimes prefer to bend. This is the quantum-mechanical basis of refraction.

In order to maximise the probability that photons from A will end up precisely at B, those going in a straight line need to be slowed down relative to those taking a more circuitous route, so that, in effect, all hit B the same time. This can be done by forcing the former to pass through more glass than the latter. The result is a round piece of glass that is thick in the middle, where the straight-line path crosses, and tapers off towards the edge, where the less direct routes do—in other words, a focusing lens, with its focal point at B.

Dr Capasso’s lens, described in Nano Letters, also slows photons down. But instead of using varying thickness of glass to do the job, he and his team created an array of antennae which absorb photons, hold on to them for a short time and then release them. In order for this trick to work, though, the distance between the antennae has to be smaller than the wavelength of the light being focused. In Dr Capasso’s case that means less than 1,550 nanometres, though he thinks that with tweaking it could be made to work with shorter-wavelength visible light, too.

Creating the array involved coating a standard silicon wafer, 250 microns thick, with a 60-nanometre layer of gold. Most of this layer was then stripped away using a technique called electron-beam litography, leaving behind a forest of V-shaped antennae arranged in concentric circles. By fiddling with their precise shape, after much trial and error, antennae lying on different circles could be coaxed into holding on to the photons for slightly different lengths of time, mimicking an ordinary glass lens. The whole fragile system can be sandwiched between two sheets of transparent material to make it more robust.

At present the new-fangled lens only works for monochromatic light and so is unlikely to replace the glass sort in smartphone cameras anytime soon. But it could revolutionise instruments that rely on single-colour lasers, by making further minaturisation possible while eliminating the optical aberrations inherent to glass lenses. Such devices include laser microscopes, which are used to capture high-resolution images of cells, or optical data storage, where a more accurate and smaller lens could help squeeze more information into ever less space.

First published on economist.com.

References: 

  1. Capasso et al., Aberration-Free Ultrathin Flat Lenses and Axicons at Telecom Wavelengths Based on Plasmonic Metasurfaces, Nano Letters2012.
  2. Capasso et al., Light Propagation with Phase Discontinuities: Generalized Laws of Reflection and Refraction, Science2011.

Also appeared in The Economist. Also available in audio here.

Image credit: Francesco Aieta