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Low-fat curd intake in pregnancy could trigger asthma in children

NEW DELHI MONDAY 19 | SEPTEMBER 2011

SCIENCE+HEALTH

Drug eluting balloon technology is a new way to treat heart blockages

50 YEARS AGO IN DECCAN CHRONICLE

UN CHIEF DIES IN PLANE ACCIDENT Ndola (North Rhodesia), Sept.

18: Dag Hammarskjoeld was killed when his plane crashed seen and a half miles from Ndola today. The U.N. Secretary-General’s body was among the six found in the wreckage.

Another person who was not immediately identified was found seriously injured. Mr Hammarskjoeld’s plane a DC6 airliner, crashed in the bush seven and a half miles from Ndola. The wreckage was spotted by a Royal Rhodesian Air Force provost aircraft.

A Northern Rhodesia Government spokesman confirmed that the wreckage found was that of Mr Hammarskjoeld’s plane. He also confirmed that Mr Hammarskjoeld’s body had been identified.

The spokesman said the wreckage was first seen by an African charcoal burner and then later spotted by a provost aircraft of the Royal Rhodesian Air Force. The spokesman said that when a search party reached the wreckage at 3.15 pm today it was still smoldering. Six bodies, including that of Mr Hammarskjoeld, were found near the aircraft.

The spokesman said that it appeared that the aircraft had struck the ground at speed and with considerable force.

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DINO-KILLING ASTEROID WIPED OUT BIRDS: STUDY Washington: The catastrophic meteor strike that killed dinosaurs on earth some 65 million years ago may also have wiped out ancient birds, scientists say.

Palaeontologists who examined fossils of ancient birds found that many of the archaic birds died off at the end of the Age of Dinosaurs.

According to the researchers, nearly all the modern bird groups, from owls to penguins and so on, began to emerge within 15 million years after all the dinosaurs went extinct. These birds are subtly but significantly different from many of the ancient lineages that existed before a cosmic impact that wreaked havoc around the globe at the end of the Cretaceous period about 65 million years ago, they said.

“These archaic birds superficially looked very similar to modern birds, but underneath their feathers they were completely different,” study researcher Nicholas Longrich, said.

— PTI

NEW WAY TO KILL CANCER CELLS DISCOVERED Washington: Scientists have figured out a new way to kill cancer cells by disabling a protein known as fortilin, which promotes their unbridled growth. Fortilin does so by neutering (removing) protein p53, which actually suppresses cancer.

This finding potentially paves the way for treating a range of tumours and atherosclerosis (hardening of arteries, with plaque buildup), which p53 also helps prevent.

“The p53 protein is a critical defence against cancer because it activates genes that induce apoptosis, or the death of cells,” said Ken Fujise, director cardiology division, University of Texas Medical Branch, who led the study.

Fujise and his team used animal models to demonstrate that fortilin inhibits p53 from activating genes, such as BAX and Noxa, that facilitate cell death. Thus, cells that would be killed are allowed to proliferate, the Journal of Biological Chemistry reports.

“When normal cells become cancer cells, our bodies’ natural biological response is to activate p53, which eliminates the hopelessly damaged cells,” said Fujise, according to a Texas statement.

— IANS

A search for relief

through Arnica Bee-Shyuan Chang

■ Derived from a flower, arnica is used to promote many kinds of healing.

It is available in pellets, topical gels, creams and even massage oil

B

Aashima Dogra

diary

N

Dr Macrene AlexiadesArmenakas, a Manhattan dermatologist and an assistant clinical professor at Yale, said that, “taken orally, arnica has been reported to cause irritation and toxicity for both the gastrointestinal system and the kidneys”.

Still, even before the style set took it up, sports figures were showing interest in the substance.

Pierre Barrieu, a former head fitness coach for the United States Men’s National Soccer Team, had been treating players with arnica pellets and topical formulations since 2002.

“Basically, it was to relieve the effects of blows and bruises (i.e., prevent swelling and bleeding) when applied in a timely manner,” he wrote in an email. “It’s best to apply as early as possible after the traumatic event. We also used it to accelerate the recovery, because arnica decreases the inflammation. And finally, it was used to prevent cramps.”

Orthopaedic surgeons have also “prescribed” arnica, which is sold in places like Duane Reade and Whole Foods, as a pre- and postoperative measure. And some dermatologists have recommended it after plastic surgery and injectables like Botox and Restylane.

When the fashion designer Diane Von Furstenberg was injured in a ski accident in January, she tweeted during recovery: “Arnica gel is the best thing you can do for bruises... I cannot say it enough...,” prompting rumours that the accident was a foil for plastic surgery (which she quickly batted away).

In the hands of natural-beauty buffs, arnica has recently become something of a medicine-cabinet and vanity catch-all. According to Sprayology, a company featured on Teen Vogue’s website that sells vitamin and homeopathic mouth sprays, arnica treats confusion and feelings of vertigo. That’s the claim, anyway, for including the herb in its “Brain Power” formulation.

On online forums, especially of the ayurvedic and homeopathic variety, arnica oil has been touted

Wende Zomnir of Urban Decay uses arnica to prevent soreness.

— NYT as a remedy for alopecia, or hair loss. Ms Zomnir of Urban Decay used it for pain and soreness after natural delivery. “My midwife gave me arnica after the births of my boys,” she said. “I had them both at home, so no drugs available. Arnica did the trick.”

Still others say it clears up acne and other skin inflammations.

Nelsons Pure and Clear Acne Gel lists arnica as one of four active ingredients. In an Elle magazine interview, the model Gisele Bundchen touted Nelson’s gel as a gentle way to clear up blemishes.

Derived from a yellow mountain daisy that grows in Europe and is also known as leopard’s bane, arnica has traditionally been used to treat bruising

And at the Upper East Side Kiehl’s flagship and spa, which opened on July 19, jars of arnica flowers line the treatment rooms so aestheticians can customise services on the spot. It’s visually attractive from a naturist’s standpoint, but not the most contemporary method.

“Arnica has evolved,” said Dr Alexiades-Armenakas.

“Even though it has a long history, it’s never been terribly effective. Fast forward to the present, and we’ve had a good amount of labs analyse the active ingredients in arnica.

They’ve identified a number of ingredients that account for antibruising, and among them are caffeine derivatives.”

Dr Alexiades-Armenakas has included these derivatives along with cacao extract in her 37 Extreme Actives facial cream, sold at Neiman Marcus for $295 for a 1.7-ounce pot. “The idea is to combat puffiness because caffeine has a constrictive ability on blood vessels and lymphatic vessels,” she said.

Dr Charles Passler, a Manhattan chiropractor and nutritionist who has worked with the Estée Lauder model Carolyn Murphy and with Dylan Lauren, recommends both oral and topical forms of arnica, mainly for bruising and inflammation.

“As far as using arnica as a tool for changing body composition, I’m not aware of it,” he said. For temporary de-bloating, though, Dr Passler conceded, “It will help decrease any puffiness in the body caused by inflammation.”

Despite her use of arnica in a topical product, Dr AlexiadesArmenakas remains concerned about long-term oral use. “I would be OK if they did it for a few days for a photo shoot once a month,” she said of the fashionable pillpoppers.

“But if they’re having a photo shoot every week, and they’re regularly on it, I would be very worried. Especially for models, they’re very thin, and it’s easier to get toxicity.”

By arrangement with the New York Times

In diamonds’ flaws, finding clues to earth’s carbon cycle Nicholas Wade

meanwhile ■ Gemstones that once lay more than 435 miles beneath the earth’s surface and that include chemical signatures of the extinct ocean floor are shedding light on the planet’s carbon cycle

x New trends make a splash at UK fest

focus

efore the CFDA Fashion Awards in June, the New York-based fashion designer Phillip Lim, who’d been travelling frequently and working hard, was feeling a bit puffy. “I heard of models and other designers taking arnica before big events or photo shoots, so I thought I’d try it out,” he said recently, referring to the homeopathic supplement arnica montana. “It’s supposed to slim you down because it flushes you out. And it clears up your skin.”

Mr Lim tried a three-day oral regimen of arnica before walking the red carpet, and was pleased with the results. “I did feel like my skin glowed afterwards,” he said.

Available in pellets, topical gels, creams and even massage oil, arnica is the latest of many herbal remedies to invigorate, if not intoxicate, the fashion crowd.

Linda Fargo, the fashion director of Bergdorf Goodman, counts the pellet form as one of her fashion week survival must-haves, and the stylist Isabel Dupré has long been a fan.

“I know it for its healing quality,” Ms Dupre said. “It’s an old family remedy.”

Wende Zomnir, the executive creative director of Urban Decay cosmetics, who uses arnica in several forms instead of nonsteroidal anti-inflammatory drugs, said: “I think it’s amazing. I take it myself, give it to my kids and hand it out at the Crossfit gym I work out at. I use it after a tough workout to prevent muscle soreness, if myself or my kids have gotten bumped around and might be bruised, or if I’ve strained a muscle.”

Derived from a yellow mountain daisy that grows in Europe and is also known as leopard’s bane, arnica has traditionally been used to treat bruising. It reputedly increases circulation by stimulating white blood cell activity, thereby decreasing the amount of healing time and reducing inflammation. If taken internally, it must be diluted with water; arnica contains the toxin helenalin and is poisonous if consumed in large quantities.

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D

iamonds that once lay more than 435 miles beneath the earth’s surface have provided researchers with an unexpected window into the planet’s history. The diamonds, during their formation, captured evidence that slabs of the ocean floors descend deep beneath the earth’s surface, recycling carbon between the oceans and the earth’s mantle, the shell of rock, about 1,800 miles thick, that lies directly beneath the earth’s surface.

Understanding the fate of the slabs will help scientists better understand the earth’s carbon cycle and all the processes that depend on it, from the carbon dioxide in the atmosphere to the carbon compounds in living organisms and the formation of hydrocarbons in oil and gas. Objects that resemble ocean slabs can be seen in seismic recordings, but they lie far too deep for any drill to sample.

Impurities in the dia-

monds contain chemical signatures of the extinct ocean floor, evidence that the slabs have been cycled deep into the earth’s mantle, says a research team led by Michael J. Walter of the University of Bristol in England.

These microscopic impurities, derived from rock and from organic material in creatures that once lived on an ancient ocean floor, have undergone an amazing journey.

The ocean floor rock, basalt, along with the sediment that built up on top of it, was drawn down at the edge of an ocean as part of the conveyor-belt mechanism that moves the continents.

When the slab of ocean floor had plunged 435 miles beneath the surface, minerals from the basalt were encapsulated inside the diamonds that formed at these depths.

The diamonds continued to descend with the slab of ocean floor until they experienced two elevator rides back to the

surface. A rising mass of solid rock known as a mantle plume carried them slowly back toward the upper mantle, and the heat of the plume then propelled to the surface an explosive jet of molten kimberlite, a volcanic rock that preserves diamonds.

Eons later, the diamonds were mined by the Rio Tinto Group from Juina in Brazil. The company allowed members of the research team to sift through stones not deemed to be of gem quality. After examining thou-

Superdeeps will emerge in 10 years as some of the strongest evidence for deep movements in earth’s mantle –– Steven B. Shirey Carnegie Institution

sands of diamonds, the researchers found just six that seemed to be of superdeep origin.

Despite their deep origin, the Juina diamonds are comparatively young as diamonds go. They were formed only 100 million years ago. Most gemquality diamonds are 1 billion to 3.5 billion years old, and originate at shallower depths, in the keels beneath the cratons, the ancient blocks of rock that form the hearts of the earth’s continental masses. The impurities that make the superdeep diamonds useless to the jeweller are invaluable to the scientist. From the inclusions in the six Juina diamonds, Dr Walter’s team was able to infer the existence of two minerals that form only in conditions that exist 435 miles or

ew scientific trends are hardly unfounded at the British Science festival.

It is here that the term “scientist” was coined and the word “dinosaur” was first used. Brand new research showcased at this years festival:

letes can be directly attributed to use of technology in sporting events. Prof. Steve Haake of Sheffield Hallam University warned sportgoverning authorities of stagnation in world sport records as a result of banning new technology. His work reveals the lack of any new records since the ban on the hydrodynamic swimsuits after the Beijing Olympics. If the ban persists and records are not re-set, these records could remain “untouched for decades”.

POPULAR COSMOLOGY MODEL NEEDS REVISION

The outcome of the overmilitarised reaction after 9/11 has been radically different than expected.

Prof. Paul Rogers from Bradford University presented results of his study on post-9/11 events.

“The analysis of the first ten years of the ‘war on terror’ after 9/11 examines the expected outcomes of the war, including a defeated Al Qaeda movement, stable and pro-western states in Iraq and Afghanistan, and a diminished Iran. It contrasts these with the actual outcomes, including over 2000,000 people killed, over seven million refugees, and an unstable Iraq, a more influential Iran and a war in Afghanistan about to enter its second decade.”

He suggested 9/11 should have been treated as an event of “transnational criminality” and dealt with action by a stronger Interpol and a decisive international justice system.

WAR ON TERROR WAS A MISTAKE

Our view of the cosmos might need correction.

Four per cent of our universe is formed of matter, 21 per cent is dark-matter and the rest is dark energy. All experiments looking for direct evidence of dark matter are based on the standard model of cosmology. This model doesn’t stick in the simulation of dwarf galaxy formation (believed to be made up of dark matter) created by Durham scientists. Announcing the results of their study, Prof.

Carlos Frenk expressed his concern over inconsistency of the standard model and indicated it needed revision before any dark matter was to be found.

RARE ELEMENTS GROWING SPARSE Rare earth elements used in manufacture of mobile gadgets will soon be in short supply. To meet future demands these elements will need to be mined at undiscovered locations or recycled from electronic waste.

China supplies 97 per cent of the world’s rare earth elements.

TECHNOLOGY NEEDS SPORT The gradual fall in performance times of athdeeper below the earth’s surface. The composition of the two minerals matched the basalt of which the ocean floor is made, showing that slabs of ocean floor had reached this depth, the researchers reported online on Thursday in the journal Science.

In another test, they showed that the carbon in the impurities contained less than usual of the isotope known as carbon 13, a signature of organic carbon at the surface of the earth that has been processed by living organisms. Researchers are delighted that so much information about major geological processes can be gleaned from the microscopic impurities in the superdeep diamonds.

“The superdeeps will probably emerge in the next 10 years as some of the strongest evidence for deep movements and pathways in the earth’s mantle,” said Steven B. Shirey of the Carnegie Institution of Washington, a member of Dr Walter’s team.

Thomas Stachel, an expert on diamond geochemistry at the University of Alberta in Canada, said, “Here you have a beautiful demonstration that the oceanic plate cycle is not relatively shallow, as many peo-

ple assume, but that the subducted plate makes it down to the deep mantle and is brought back to the surface by a mantle plume.”

In Dr Walter’s laboratory, the superdeep diamonds are polished with a jeweller’s polishing wheel until the precious impurities within them are exposed. With a variety of spectroscopic tests, the researchers then measure the composition of the minerals within the impurities.

The discovery that carbon from the ocean floor can be mixed so deep within the mantle raises the larger question of how much of the ocean floor and sediments are carried to the deep mantle. Given the importance of carbon to life, scientists seek to understand the major reservoirs of carbon in the earth and the exchanges between them, both in space and in time.

“The mantle is the biggest reservoir of carbon, and we know very little about it,” Dr Walter said.

“This won’t affect climate tomorrow, but what our results tell you is that carbon from the surface can go all the way into the lower mantle, which may be a long-term sink for carbon.”

By arrangement with the New York Times

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SCIENCE+HEALTH As permafrost thaws, scientists study risks US approves first mechanical cardiac assist device for kids

NEW DELHI MONDAY 19 | DECEMBER 2011 50 YEARS AGO IN

INDIAN FORCES ENCIRCLE PANJIM

Belgaum: India’s defence forces had reached the very gates of Panjim, capital of Goa and were poised for a formal entry into Panjim tomorrow morning, according to latest reports received here around midnight tonight. India’s defence forces moved into Goa early this morning after Portuguese has rejected every effort of PM Jawaharlal Nehru for the last 15 years and more to settle the issue peacefully. The Portuguese who had been subjecting the people of Goa to tyranny all these years fled in panic as defence forces closed in on Panjim by using the minimum force.

As the Indian defence forces advanced towards the capital on a three-pronged drive from the north, south, and east, town after town fell in a military sense, but actually the towns’ people received the troops from the motherland with open arms amidst scenes of jubilation and rejoicing by the local people, while the Portuguese fled in panic abandoning their positions even before they were attacked, reports from the front said.

Cooperating with the Indian forces in every possible way, the local people pointed out to the Indian troops the places where mines had been laid, provided them with boats and ferried them across the rivers and waterways.

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London: A daily dose of Vitamin B can radically combat memory loss in old age and even help protect against Alzheimer’s disease, a new study has found. More than 250 people took part in the study, at Oxford University, including people with mild cognitive impairment who were aged 70 years or older.

They were given Vitamin B, found naturally in food such as beans, meat, wholegrains and bananas, or a placebo over a two-year period. Taking the food supplement appeared to help maintain mental processes, such as planning, organising and recalling information.

The researchers found that people taking the pill had lower levels of a brain protein known to lead to a rise in the risk of dementia.

They found that it also slowed mental decline in older people who have slight problems with their memory.

— ANI

PLASMA CAN HELP KNOCK OUT DEADLY VIRUSES: RESEARCH Sydney: Adenoviruses that can cause respiratory, eye, and intestinal tract infections, must adopt the cellular machinery of infected organisms to produce more of their own, scientists suggest.

Scientists from Chinese and Australian universities have found a way to disrupt the hijacking process by using plasma to damage the viruses before they come into contact with host cells.

The research led by Z. Xiong and X. Lu (HuaZhong University of Science and Technology, China) and K. Ostrikov (University of Sydney, Australia), prepared solutions containing adenoviruses.

They then subjected the samples with a low-temperature plasma, a highly energised state of matter which is created by applying a voltage to a gaseous mixture in a syringe, the journal Applied Physics Letters reported. The plasma damaged the viral DNA. When the virus solutions were later added to colonies of embryonic kidney cells, plasma-treated samples showed much less viral activity, a university statement said.

— IANS

Depressed teen girls are twice as likely to start binge eating: Study

If humanity began getting its own emissions under control soon, the greenhouse gases emerging from permafrost could be kept to a much lower level

Justin Gillis

focus ■ Experts worry that if the permafrost thaws in the Northern Hemisphere, huge amounts of carbon will be released into the air, greatly intensifying global warming

A

VITAMIN B CAN HELP BEAT MEMORY LOSS, ALZHEIMER’S

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bubble rose through a hole in the surface of a frozen lake. It popped, followed by another, and another, as if a pot were somehow boiling in the icy depths. Every bursting bubble sent up a puff of methane, a powerful greenhouse gas generated beneath the lake from the decay of plant debris.

These plants last saw the light of day 30,000 years ago and have been locked in a deep freeze — until now. “That’s a hot spot,” declared Katey M. Walter Anthony, a leading scientist in studying the escape of methane. A few minutes later, she leaned perilously over the edge of the ice, plunging a bottle into the water to grab a gas sample.

It was another small clue for scientists struggling to understand one of the biggest looming mysteries about the future of the earth. Experts have long known that northern lands were a storehouse of frozen carbon, locked up in the form of leaves, roots and other organic matter trapped in icy soil — a mix that, when thawed, can produce methane and carbon dioxide, gases that trap heat and warm the planet. But they have been stunned in recent years to realise just how much organic debris is there.

A recent estimate suggests that the perennially frozen ground known as

— NYT

In an Alaskan lake, bubbles of methane, a potent greenhouse gas, collect beneath the ice. permafrost, which underlies nearly a quarter of the Northern Hemisphere, contains twice as much carbon as the entire atmosphere. Temperatures are warming across much of that region, primarily, scientists believe, because of the rapid human release of greenhouse gases.

Permafrost is warming, too. Some has already thawed, and other signs are emerging that the frozen carbon may be becoming unstable.

“It’s like broccoli in your freezer,” said Kevin Schaefer, a scientist at the National Snow and Ice Data Center in Boulder, Colorado. “As long as the broccoli stays in the freezer, it’s going to be OK. But once you take it out of the freezer and put it in the fridge, it will thaw out and eventually decay.”

If a substantial amount of the carbon should enter the atmosphere, it would intensify the planetary warming. An especially worrisome possibility is that a significant proportion will emerge not as carbon dioxide, the gas that usually forms when organic material breaks down, but as methane, produced when the breakdown occurs in lakes or wetlands. Methane is especially potent at trapping the sun’s heat, and the potential for large new methane emissions in the Arctic is one of the biggest wild cards in climate science.

Scientists have declared that understanding the problem is a major priority. The United States department of energy and the European Union recently committed to new projects aimed at doing so, and Nasa is considering a similar plan.

But researchers say the money and people devoted to the issue are still minimal compared with the risk.

For now, scientists have many more questions than answers. Preliminary computer analyses, made only recently, suggest that the Arctic and sub-Arctic regions could eventually become an annual source of carbon equal to 15 per cent or so of today’s yearly emissions from human activities.

But those calculations were deliberately cautious.

A recent survey drew on the expertise of 41 permafrost scientists to offer more informal projections.

They estimated that if human fossil-fuel burning remained high and the planet warmed sharply, the gases from permafrost could eventually equal 35 per cent of today’s annual human emissions.

The experts also said that if humanity began getting its own emissions under control soon, the greenhouse gases emerging from permafrost could be kept to a much lower level, perhaps equivalent to 10 per cent of today’s human emissions.

Even at the low end, these numbers mean that the long-running international negotiations over greenhouse gases are likely to become more difficult, with less room for countries to continue burning large amounts of fossil fuels. In the minds of most experts, the chief worry is not that the carbon in the permafrost will break down quickly — typical estimates say that will take more than a century, perhaps several — but that once the decomposition starts, it will be impossible to stop.

“Even if it’s 5 or 10 per cent of today’s emissions, it’s exceptionally worrying, and 30 per cent is humongous,” said Josep G. Canadell, a scientist in Australia who runs a global programme to monitor greenhouse gases. “It will be a chronic source of emissions that will last hundreds of years.”

A troubling trend has emerged recently: Wildfires are increasing across much of the north, and early research suggests that extensive burning could lead to a more rapid thaw of permafrost.

RISE AND FALL OF PERMAFROST Standing on a bluff the other day, overlooking an immense river valley, A. David McGuire, a scientist from the University of

Alaska, Fairbanks, sketched out two million years of the region’s history. It was the peculiar geology of western North America and eastern Siberia, he said, that caused so much plant debris to get locked in an ice box there. These areas were not covered in glaciers during the last ice age, but the climate was frigid, with powerful winds. The winds and rivers carried immense volumes of silt and dust that settled in the lowlands of Alaska and Siberia.

A thin layer of this soil thawed on top during the summers and grasses grew, capturing carbon dioxide. In the bitter winters, grass roots, leaves and even animal parts froze before they could decompose. Layer after layer of permafrost built up. At the peak of the ice age, 20,000 years ago, the frozen ground was more extensive than today, stretching deep into parts of the lower 48 states that were not covered by ice sheets.

Climate-change contrarians like to point to that history, contending that any melting of permafrost and ice sheets today is simply the tail end of the ice age.

Citing permafrost temperatures for northern Alaska — which, though rising rapidly, remain well below freezing — an Organization called the Center for the Study of

Carbon Dioxide and Global Change claimed that permafrost is in “no more danger of being wiped out any time soon than it was in the days of our greatgrandparents.”

But mainstream scientists, while hoping the breakdown of permafrost will indeed be slow, reject that argument. They say the climate was reasonably stable for the past 10,000 years or so, during the period when human civilisation arose. Now, as people burn immense amounts of carbon in the form of fossil fuels, the planet’s temperature is rising, and the Arctic is warming twice as fast. That, scientists say, puts the remaining permafrost deposits at risk.

For several decades, researchers have been monitoring permafrost temperatures in hundreds of boreholes across the north. The temperatures have occasionally decreased in some regions for periods as long as a decade, but the overall trend has been a relentless rise, with temperatures now increasing fastest in the most northerly areas.

Thawing has been most notable at the southern margins. Across huge areas, including much of central Alaska, permafrost is hovering just below the freezing point, and is expected to start thawing in earnest as soon as the 2020s.

In northern Alaska and northern Siberia, where permafrost is at least 12 degrees Fahrenheit below freezing, experts say it should take longer. “Even in a greenhouse-warmed world, it will still get cold and dark in the Arctic in the winter,” said Mark Serreze, director of the snow and ice data center in Boulder.

Scientists need better inventories of the ancient carbon. The best estimate so far was published in 2009 by a Canadian scientist, Charles Tarnocai, and

some colleagues. They calculated that there was about 1.7 trillion tons of carbon in soils of the northern regions, about 88 per cent of it locked in permafrost. That is about two and a half times the amount of carbon in the atmosphere.

Philippe Ciais, a leading French scientist, wrote at the time that he was “stunned” by the estimate, a large upward revision from previous calculations. “If, in a warmer world, bacteria decompose organic soil matter faster, releasing carbon dioxide,” Dr Ciais wrote, “this will set up a positive feedback loop, speeding up global warming.”

PLUMES OF METHANE Katey Walter Anthony had been told to hunt for methane, and she could not find it. As a young researcher at the University of Alaska, Fairbanks, she wanted to figure out how much of that gas was escaping from lakes in areas of permafrost thaw. She was doing field work in Siberia in 2000, scattering bubble traps around various lakes in the summer, but she got almost nothing.

Then, that October, the lakes froze over. Plumes of methane that had been hard to spot on a choppy lake surface in summer suddenly became more visible. “I went out on the ice, this black ice, and it looked like the starry night sky,” Dr Walter Anthony said.

“You could see these bubble clusters everywhere. I realised — ‘aha!’ — this is where all the methane is.”

When organic material comes out of the deep freeze, it is consumed by bacteria. If the material is well-aerated, bacteria that breathe oxygen will perform the breakdown, and the carbon will enter the air as carbon dioxide, the primary greenhouse gas.

But in areas where oxygen is limited, like the bottom of a lake or wetland, a group of bacteria called methanogens will break down the organic material, and the carbon will emerge as methane.

Scientists are worried about both gases. They believe that most of the carbon will emerge as carbon dioxide, with only a few percent of it being converted to methane.

By arrangement with the New York Times

Joy of feeding, without all the parental angst T

Aashima Dogra

diary

Perri Klass

meanwhile ■ While the number of obese babies is not on the rise, some of our standard infant feeding practices and attitudes may need revising

B

ack before computers moved into our exam rooms, I tended paper growth charts ritually at every checkup.

Pink for girls, blue for boys. Age on the X-axis, weight on the Y-axis. I paid particular attention to the charts of infants, plotting weight and length

and head circumference with my pen month by month to show parents how their babies were growing, to reassure them when they worried that there wasn’t enough breast milk or because their babies were spitting up a little.

It’s a primal impulse to worry about an infant’s growth. But experts on child nutrition, mostly enlisted nowadays in the battle against childhood obesity, point out that some of our standard infant feeding practices and attitudes may need revising, including some of those encouraged by pediatricians like me. My grandmother’s attitude — stuff food into the baby, be proud of a “good eater” — may not make sense in an environment of abundant food and rising obesity.

But it gets medically controversial, and emotionally sticky, when doctors start talking about obesity in babies. Is there an epidemic of infant obesity?

Are fat babies at greater risk of turning into fat children at higher risk for medical consequences later on in life? And what

can doctors advise parents about feeding a baby — which ought, after all, to be one of the basic joys of parenthood?

The answers to those questions aren’t always clear. Scientists do know that the number of obese children has been on the increase. But not the proportion of those under age 2 whose weight-for-length curve is at the 95th percentile or above — that has held pretty steady since 1999.

Perhaps more important, no one wants to see babies on diets, no one wants to see hungry babies not given food. Dr Elsie M. Taveras, a paediatrician on the faculty at Harvard Medical School and a leading expert on obesity risk factors in children, says that the evidence indicates

that when parents too severely restrict a child’s food intake, that child is at higher risk for obesity.

“When we are overly controlling, either overly restrictive or we overly pressure a child to eat, that doesn’t allow the child to respond to their own hunger and satiety,” she said.

Satiety cues (spitting out the bottle or the breast, turning the head away, closing the mouth) are the signals that infants send when they’ve had enough to eat. One promising line of research involves helping parents recognize babies’ hunger signals (rooting, putting a hand to the mouth, sucking mouth movements) and when they’re saying that they’ve had enough.

Decades ago, “we really were more worried, and needed to be more worried, about failure to thrive,” said Leann L. Birch, director of the Centre for Childhood Obesity Research at Penn State. “Overfeeding seems to be more dangerous these days.”

By arrangement with the New York Times

he tsunami-destroyed nuclear reactors at Fukushima, Japan have reached a “cold shutdown”. This means the temperature in each of the three vessels is now well below a 100 degrees. From here on, the operators have more control and safety can be easily maintained.

Despite the cold shutdown announcement, recirculation of water will continue to cool the reactor core; environmental concerns have been raised regarding minor leakages of this now radioactive water.

Eventually, the fuel, cooling water, debris etc will be moved to another location where it can decay over the years without causing more harm. The area will then be decontaminated by removing the topsoil layer before the residents can move in. The entire process will take years, if not decades.

FAILED MARS-MOON PROBE TO FALL BACK TO EARTH The Russian Phobos-Grunt probe was designed to travel to the larger of the two Martian moons, Phobos, collect a soil sample and bring it to earth. It took off early November this year, only to fall back two months later. Roscosmos, the Russian space agency

Symbolic cooling of Fukushima announced last week that after losing contact with the 13.2 tonne probe, it will start crash landing next month; and most of it will disintegrate on its way down including the 11 kg of toxic fuel that is expected to burn 60 miles above the surface. Two hundred kg of random scrap from the probe might survive the reentry, crashing into an unknown location anywhere on earth — the exact coordinates can be calculates only 2-3 days before the descend. What was to be china’s first Mars satellite, Yinghuo-1, that piggybacked on the probe, will also descend into its doom with the stranded probe.

COCAINE IN THE AIR A group of Italian scientists collected air from different sites and tested it for illicit drugs and the usual air pol-

lutants. They found that the airborne concentration of cocaine was linked to the number of drug seizures my the police in the area.

This might form the basis of detecting comparable drug use prevalence in cities or communities.

LOVEJOY SURVIVES SUN’S WRATH A seemingly suicidal comet survived a close encounter with our star. Comet lovejoy, named after the amateur observer who identified it only a few weeks ago, was expected to be destroyed by the sun’s heated outer atmosphere where temperature go up to 6000 degrees and its powerful magnetic field. Lovejoy did not pass the sun unscathed, only 10 per cent of it survived the encounter and it has lost its tail.