Brain link to anti-social and yobbish behaviour in teenagers

Brain link to anti-social and yobbish behaviour in teenagers - Bad behaviour in teenagers could be explained by stunted growth of the "caring-sharing" areas of their brains, study suggests.

Scientists have found that yobs and hoodies have smaller regions of the brain that deal with emotions especially fear and the ability to feel the pain of others.

This suggests that their anti-social behaviour could have a biological basis and could lead to possible new treatments.

Brain link to anti-social and yobbish behaviour in teenagers

The study led by Cambridge University attempted to explain why five per cent of school age children suffer from Conduct Disorder (CD), a recognised psychiatric condition characterised by aggressive and anti-social traits.

They looked at 63 boys with an average age of 18 with CD, some of whom developed problems at an early age and some who began to display anti-social behaviour in adolescence.

They were compared with a group of 27 "normal" teenagers from similar backgrounds.

Brain scans showed that two regions were significantly smaller in affected teenagers, including those who only became badly behaved when they reached adolescence.

The two areas were the amygdala and insula, which contribute to emotional perception, empathy, and the ability to recognise when others are in distress.

Rates of CD have increased sharply around the world since the 1950s.

The condition can develop in young children, or not show itself until the teenage years.

Those affected are at greater risk of mental problems, substance abuse and criminality in later life.

It has long been thought that adolescent-onset CD is merely the result of susceptible teenagers imitating badly-behaved peers.

But the new research challenges this view, pointing to brain changes that affect all youngsters with the condition.

The scientists are cautious about how to interpret the findings, published in the American Journal of Psychiatry.

Professor Ian Goodyer, one of the researchers, said: "We hope that our results will contribute to existing psychosocial strategies for detecting children at high risk of developing anti-social behaviour."

He stressed their study had not demonstrated a foolproof "test" and only provided a springboard for further, more extensive, research.

He said environmental and family factors also played a part.

Dr Graeme Fairchild, co-author from the University of Southampton, said: Changes in grey matter volume in these areas of the brain could explain why teenagers with conduct disorder have difficulties in recognising emotions in others.

"Further studies are now needed to investigate whether these changes in brain structure are a cause or a consequence of the disorder."

Dr Andy Calder, from the Medical Research Council's Cognition and Brain Sciences Unit, another author, said: "Only when we are confident that we understand why the disorder develops can we apply this knowledge to the further development and evaluation of treatments.

"The disorder has a devastating impact on families and communities and at the moment we have few effective treatments." ( telegraph.co.uk )

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The digital revolution is making Earth harder to detect by inquisitive aliens, world's leading ET hunter says

The digital revolution is making Earth harder to detect by inquisitive aliens, world's leading ET hunter says. Satellite TV and the digital revolution is making humanity more and more invisible to inquisitive aliens on other planets, the world's leading ET hunter said today.

That might be good news for anyone who fears an 'Independence Day' - style invasion by little green men.

But it is also likely to make the search for extra-terrestrial intelligence by Earthly scientists harder, Dr Frank Drake believes.

Out of reach? E.T. touches his friend Elliot in the film 'E.T The Extra Terrestrial'. Dr Frank Drake believes the digital revolution is making us harder for other life forms to detect

Dr Drake, who founded the SETI (Search for Extra-terrestrial Intelligence) organisation in the US 50 years ago, said the digital age was effectively gagging the Earth by cutting the transmission of TV and radio signals into space.

At present, the Earth was surrounded by a 50 light year-wide 'shell' of radiation from analogue TV, radio and radar transmissions, he said.

But although the signals had spread far enough to reach many nearby star systems, they were rapidly vanishing before the march of digital technology.

To a race of observing aliens, digital TV signals would look like noise, said Dr Drake.

Scientist Frank Drake said the digital age was effectively gagging the Earth

Digital transmissions were also much weaker than their terrestrial equivalent.

While old-style TV transmitters might generate one million watts, the power of a satellite signal was around 20 watts.

Satellites also aimed their transmissions at the Earth, with almost none being allowed to escape into space.

Use of cable prevented the leakage of signals even more effectively.

'Now the actual amount of radiation escaping into space is about two watts, not much more than you get from a cell phone,' said Dr Drake.

'If this continues into the future very soon our world will become undetectable. Using ourselves as an example, it means the difficulty of finding other civilisations will be much greater.

'We're going to have to search many more stars and many more frequencies.'

Any alien civilisations that existed were likely to be far more advanced than ours, he said. Their analogue TV age probably came and went long ago, before humans even thought about searching the sky for signs of intelligent life.

Dr Drake was speaking at a discussion meeting taking place at the Royal Society in London entitled 'The Detection of Extra-terrestrial Life and the Consequences for Science and Society'.

He said he remained convinced that intelligent life existed beyond the Earth, despite the lack of success of SETI scientists who have spent half a century tuning into the stars.

Research scholars hold up the original Drake equation which estimates the chances of finding ET

The famous 'Drake Equation' which he invented to estimate the chances of finding ET indicated there might be 10,000 detectable civilisations in our galaxy, the Milky Way.

However, even this large number equated to just one in 10 million stars.

'We have to search 10 million stars for signals and we have to do it over and over,' said Dr Drake. 'We haven't remotely come close to that.'

Aliens could reveal themselves with technologies that are currently far beyond the scope of humans, he pointed out.

One possibility was using your own star as an incredibly powerful lens to amplify light and radio signals.

This could be done because of the way gravity bends light, as demonstrated by Albert Einstein.

Protection? Devastation as aliens attack Earth in the science fiction film Independence Day. People afraid of an alien invasion will welcome the idea of Earth becoming undetectable

The Sun bent light from distant stars to a focal point where one million-fold magnifications should be possible, dwarfing the abilities of the most powerful telescopes.

Unfortunately, the focal point is far beyond the edge of the Solar System and too far to reach using current technology, said Dr Drake.

But it was likely advanced civilisations elsewhere had mastered the technique, he added.

A 'gravitational lens' of this type could be powerful enough to map the continents and oceans of a planet in a distant star system.

Reversing the technology to use the lens as a transmitter instead of a receiver would enable aliens to beam massively powerful signals across the galaxy, said Dr Drake.

They could be using such a system to announce their presence to other planets, he said. But although the signal would be strong, it was likely to be transient as the beam was swept from place to place.

Another method of communication could be through the use of incredibly powerful pulsed lasers, such as those now being developed for nuclear fusion reactors.

Such a laser would produce a flash that for an instant could outshine a star. SETI had now started to look for signals of this type, so far with no success.

'In the universe elsewhere there is intelligent life. I'm confident about that, but how easy it is to find we don't know,' said Dr Drake. ( dailymail.co.uk )

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Don't Sweat the Invasion

Don't Sweat the Invasion. Why foreign plants and animals may not be that bad. Tamarisk, a Eurasian shrub, is your classic invasive species—designated one of America's "least wanted" plants by the National Parks Service. In recent decades, it has spread along Southwestern riverbanks, replacing native trees such as willows and cottonwoods.

For nature lovers in the region, tamarisks (also known as saltcedars) rank somewhere between Land Rovers and James Inhofe. Measures to thwart them include burning, herbicides, and "tammy whacking" (physical removal sometimes done by freelance volunteers). A few years ago, the USDA let loose thousands of leaf-eating Asian beetles in order to sic them on tamarisks, which die from the defoliation.

But these efforts to oust the intruder have encountered a glitch. It turns out that a charismatic endangered bird—the southwestern willow flycatcher—is known to nest in the offending shrubs. Last March, the Center for Biological Diversity sued the government, charging that indiscriminately killing tamarisks jeopardizes the flycatcher.

A recent article in the journal Restoration Ecology goes even further in the weed's defense. Tamarisks are widely thought to hog water and drive out other vegetation, but the authors dispute that theory. In their view, the newcomer may just be better suited than the natives to an environment altered by human activities.

These controversies highlight a broader debate within "invasion biology," a field that emerged in the 1980s. Some scientists—such as Matthew Chew, Dov Sax, and Mark Davis—are challenging what they consider old prejudices about "alien" species. They point out the inevitability of change and the positive roles that non-natives can play in ecosystems, while describing eradication projects as often wasteful and even counterproductive.

The outlook of the more traditional camp goes something like this: While most non-natives are harmless, a minority—about 10 percent—cause serious damage. Some pose threats to human health (H1N1 is an invasive species), while others, such as agricultural pests, wreak economic havoc. A third category dramatically changes landscapes. (Think kudzu, the creeping vine that has conquered the Southeastern United States.) And since these effects are unpredictable—sleeper species can seem benign for decades—all exotics are suspect.

The hard-liners promote a "guilty until proven innocent" approach to biological foreigners, including a strict "white list" of those allowed to enter each country. As globalization accelerates the movement of species, vigilance is more important than ever. Climate change adds another wildcard, making the behavior of organisms all the harder to foresee.

Now a growing contingent of scientists is advocating a more neutral attitude. Certainly, they say, non-native plants and critters can be terribly destructive—the tree-killing gypsy mothSouthern Pine Beetle can cause similar harm. The effects of exotics on biodiversity are mixed. Their entry into a region may reduce indigenous populations, but they're not likely to cause any extinctions (at least on continents and in oceans—lakes and islands are more vulnerable).

Since the arrival of Europeans in the New World, hundreds of imports have flourished in their new environments. Common wildflowers such as Queen Anne's lace and certain kinds of daisies are "naturalized" aliens. The storied comes to mind. Yet natives such as the apple tree originally hailed from Asia.

Even when species are destructive, there's the tricky question of what to do about them. We may all agree that a particular plant or animal is loathsome, but eradication isn't innocuous. Such plans tend to cost millions of dollars and often rely on toxins that bring collateral damage to other species. Biological solutions—like leaf-eating beetles and root-boring weevils—are usually considered more benign, but as the case of the tamarisk shows, they, too, can pose problems. Once an ecosystem has absorbed a new species, any targeted intervention is likely to have significant ripple effects.

The past few years have also seen active debates about the field's terminology. Some criticize the term "invasive" as too value-laden and imprecise. One widely cited definition comes from a 1999 executive order, issued by President Clinton, that aimed to ward off "alien species whose introduction does or is likely to cause economic or environmental harm or harm to human health." But what exactly constitutes "environmental harm"? It's easy to see when a power plant is hemorrhaging pollutants into the air and water—but how do you make the call when the agent of harm to nature is … also nature? Critics such as Mark Davis say we need to distinguish "harm" from "change." If an introduced species causes natives to become less abundant, does that constitute harm? Many people would say yes, but Davis doesn't ( slate.com )

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More isn't always better

Screen Saver? When it comes to cancer screening, more isn't always better. The U.S. Preventive Services Task Force has announced new mammography guidelines this week. While the task force previously encouraged screenings for women beginning at 40, it has now pushed the threshold to 50. Concerns over frequent false positives and patient anxiety influenced the group's recommendation. Though many believe that there can never be enough testing, a 2004 "Medical Examiner" by Amanda Schaffer explained that the risks of false positives, overdiagnosis, and overtreatment are real. The article is reprinted below.

Americans are enormously committed to cancer screening. In a national survey recently published by Dr. Lisa Schwartz and co-authors in the Journal of the American Medical Association, 87 percent of respondents agreed that "routine cancer screening is almost always a good idea," and 74 percent felt that early detection saves lives "most or all of the time." In fact, so enthusiastic were the survey participants that 73 percent of them said they would rather receive a free full-body CT scan than $1,000 in cash. What to make of these dramatic findings? Clearly, years of strong, scare-oriented public health messages, particularly with regard to breast cancer screening—"Don't be a victim" and similar slogans—have gotten through to the public. The dogma that more is always better when it comes to cancer screening has taken hold, undiluted by any sense of screening's drawbacks.

Yet there are drawbacks—ranging from the risk of false positives to the more complex issues of overdiagnosis and overtreatment. While early detection can certainly have benefits, it's not true that screening can only help—and can't hurt. Indeed, skeptics within the medical community, including the authors of the JAMA survey, have started to become more vocal in an effort to create a more balanced public view.

There are many types of screening, some of which are well-known: mammograms to test for breast cancer, Pap smears for cervical cancer, PSA tests for prostate cancer, fecal occult blood tests for colon cancer, and chest CT scans for lung cancer. What these tests have in common is that they look for early warning signs, including small cellular abnormalities, in healthy, asymptomatic people—sometimes as part of a checkup, sometimes as part of a public-outreach program. Most tests are suggested to patients based on age and gender—PSA tests for older men, mammography for older women. (More "comprehensive" testing is also available for the worried well through executive health programs and at medical boutiques in strip malls, where patients can undergo full-body CT scans, an aggressive form of testing generally disdained by doctors.) But just what are the risks associated with testing? Isn't more information, particularly about the vagaries of the body, always a good thing?

A Risk of False Positives

This is probably the most familiar problem associated with routine screening: Tests sometimes yield a positive result in a person who does not have cancer. Consider, for instance, PSA screening for prostate cancer in men over the age of 50: 15 percent will have elevated PSA levels while only 3 percent will in fact have cancer; that is, 12 percent will receive a false-positive result. Or consider lung cancer screening for former smokers: Between 25 percent and 60 percent will have abnormalities on a chest CT scan, though few of these irregularities will turn out to be cancer. The problem here is that patients are made to worry unnecessarily. "Cancer" is such a dreaded diagnosis in our culture—spoken of in whispers or referred to as "the C word"—that for most people, discovering that "it might be cancer" is no small thing, even if further testing is required.

Then there's the question of further testing, which, particularly for colon and lung cancer, can be fairly invasive. Lung biopsies, for example, may involve a needle passed through the chest wall or an actual open-chest surgery to remove sample tissue, depending on the location of the abnormality. Such procedures come with a host of possible complications, including infection, bleeding, partial lung collapse, pneumonia, and heart attacks, which necessarily give one pause. These problems may not occur very often—and accurate numbers are hard to come by—but former smokers, the people most likely to undergo testing, are also most likely to suffer complications since their hearts are generally weaker and their lungs don't heal as well or as quickly after biopsy.

A Risk of Overdiagnosis

Equally important, and perhaps more surprising, is the fact that some cancers will never progress to cause problems. That is to say, many more cancers are detected through screening than would ever turn out to be life-threatening or even uncomfortable for the patient (the buzzword here is "overdiagnosis"). This issue has been discussed largely for prostate cancer, in which tumors are generally slow-growing, and elderly patients sometimes die of other diseases (say, heart attacks) before their cancers cause significant symptoms. It's increasingly clear, however, that overdiagnosis occurs across the board, even in cancers long viewed as aggressive, such as lung cancer. As Dr. Barnett Kramer, associate director for disease prevention at the National Institutes of Health, said in a recent phone interview, the evidence that lung cancer, too, can be nonprogressive came as "an eye-opener"; "I would now say overdiagnosis is the rule, not the exception."

The evidence of this phenomenon is often indirect: If all of the newly discovered cases of prostate cancer, say, or of ductal carcinoma in situ, an early form of breast cancer, were destined to progress, our rates of prostate cancer mortality and of invasive breast cancer should be much higher than they are—even taking into account advances in treatment. The magnitude of overdiagnosis is difficult to pinpoint and varies from one type of cancer to another. But what's clear is that the more screening we do—and the more sensitive our technology—the more we will detect tiny cancers, many of which will be clinically insignificant.

The challenge here is to continually revise our understanding of what cancer is and how it evolves—or doesn't evolve—in the body. Not only do some abnormalities grow very slowly, some actually regress without treatment, as a result of complex interaction between precancerous cells and the body's immune system. This can be true, for example, of LSILs and HSILs, low-grade and high-grade squamous intraepithelial lesions, detected by Pap smears and linked to cervical cancer. As it turns out, through processes that are not well-understood, many—and some say most—LSILs and HSILs will simply improve on their own.

And yet another wrinkle arises from the ambiguity of some test samples: In more cases than you'd expect, pathologists disagree on whether a particular image shows cancer or not. In one especially telling study published in 1996 in Human Pathology, a panel of eight highly credentialed pathologists reviewed a series of 37 slides to determine which represented melanoma, or skin cancer, and which showed benign lesions. Surprisingly, for a significant minority of slides—38 percent of them—two or more pathologists disagreed with the majority opinion. This finding and others like it are important because they highlight the subjectivity associated with cancer diagnosis; subtle, cellular alterations may fall into a gray area between cancer and not-cancer, particularly for early stage cases—the very realm in which screening is routinely used.

A Risk of Overtreatment

Once an abnormality is labeled cancer, it is difficult for the patient and physician to "do nothing." In addition to subtle pressures on the doctor (the fear of malpractice, the prevailing standard of aggressive care), it is simply not possible to know whether a given, tiny lesion represents a case of overdiagnosis or a clinically significant finding. The inclination is usually to err on the side of caution and to proceed with treatment. But treatments can be harsh, ranging from surgery (in the case of women with DCIS) to radiation and chemotherapy, all of which have severe side effects and which no one would want to undertake unnecessarily.

The furor over mammography—triggered in part by a meta-analysis published in the Lancet in 2000—focused on the contention that screening did not reduce women's overall mortality; worse still, in one study, mortality for the screened women was actually slightly higher than for the control group, a finding attributed to overtreatment—in this case, increased heart attacks caused by radiation therapy. Radiation protocols have now been changed to minimize the heart region's exposure. But a fundamental question remains: Are there cases in which the cure is worse that the disease?

The answer is clearly yes—at least some of the time. In prostate cancer, abnormal cells are often slow-growing, and treatment can cause impotence and incontinence. Dr. Stephen Taplin, a senior scientist at the National Cancer Institute, helpfully compares some prostate cancers to gray hair, more a byproduct of aging than a life-threatening issue. "If I made men impotent and incontinent because they had gray hair, there wouldn't be any question I'd be hurting them," he said in a phone interview. But if these problems occurred as a result of aggressive cancer treatment, "most men would say, 'Doctor, you've saved me!'"

A final, terrible irony is that while screening leads to overdiagnosis and overtreatment, it also misses some cancers—and these tend to be the most aggressive, fastest-growing ones. This is because fast-growing abnormalities (for any type of cancer) are statistically more likely to develop during the window between tests, causing problems before, say, an annual screening can provide fair warning.

So how to explain the public's simple faith in testing—the significant gap between scientific evidence and popular perception? Many social and cultural pressures conspire here—and a complete catalog would no doubt include everything from physician report cards (which rate physicians according to the percentage of patients screened) to celebrity testimonials, from the financial interests of some doctors and health networks invested in imaging to the well-intentioned work of advocacy groups, particularly for women.

But one factor that has really muddied the debate deserves special mention: the "five-year survival rate," as it is called, often deployed to support screening. ("Five-year survival" represents the percentage of people diagnosed with a particular kind of cancer at a particular time who are still alive five years later.) As Dr. H. Gilbert Welch points out in his excellent book, Should I Be Tested for Cancer? this is a highly misleading statistic for the following reason: When cancers are detected early, the five-year survival rate (dated from the time of diagnosis) will necessarily improve—even if patients live no longer than they would have otherwise. Overdiagnosis further inflates the figure since more people are identified with nonprogressive cases who can be expected to live longer.

The public-health challenge, then, is to convey a more balanced, realistic message about cancer testing so that people will be receptive to negative as well as positive news about particular tests. There is good evidence to support regular Pap smears in women, no good evidence (at least not yet) to support routine lung-cancer screening for former smokers. Thus, it is particularly disheartening to see a large-scale screening program such as the New York Early Lung Cancer Action Program (full disclosure: NY-ELCAP is led by researchers at Cornell Medical School, where this writer studied medicine), which lacks a control group and so will not be able to clarify whether screening 10,000 former smokers actually saves lives. (A devastating critique of NY-ELCAP by Dr. Steven Woloshin, along with Schwartz and Welch, is available in the Lancet, but not for free.) That this massive project is heavily funded by New York's tobacco settlement fund provides a further, unfortunate twist.

Ultimately, the public needs to set aside automatic enthusiasm for screening and develop a new kind of savvy—one that balances hope with a certain dose of healthy skepticism and leads people to embark on testing only after considering a host of variables, both personal and scientific. As it turns out, in cancer screening, as in so much else, there really isn't a free lunch. ( slate.com )

READ MORE - More isn't always better

Cancer drug hope for thousands

Cancer drug hope for thousands. A drug which can extend the lives of cancer sufferers may be approved on the NHS after the manufacturer agreed to pay for extra treatments.

The drug, called trabectedin, also called Yondelis, can extend the lives of people with cancers in their soft tissues such as fat and muscle, by an average of three months.

In draft guidance the National Institute for health and Clinical Excellence recommended the drug be used on the NHS.

There are around 2,000 people in Britain with the cancer known as soft tissue sarcoma.

Nice has recommended its use where other treatments have failed or cannot be tolerated because of side effect, and where the manufacturer agrees to pay for treatment with a fifth dose if necessary.

The drug was approved under new rules in which greater weight is given to drugs that can extend the lives of people with rare diseases.

Earlier this year Nice issued draft guidance turning the drug down because of its high cost but now the maker PharmaMar has agreed to pay for treatment with a fifth dose if necessary.

Similar schemes have been applied to other drugs.

Trabectedin works by damaging the cancer cells which stops them from spreading and multiplying.

For the average patient each dose of the drug would cost aroun £3,500 and are given as an infusion into the vein over 24 hours, three weeks apart.

Around 110 patients with advanced soft tissue sarcoma will be eligible for treatment in England and Wales.

Dr Carole Longson, Health Technology Evaluation Centre Director at Nice said: “We are delighted the Independent Appraisal Committee has been able to recommend trabectedin in its draft guidance. It has certainly not been an easy decision to make; soft tissue sarcoma is a rare cancer and the evidence was limited.

“However, treatment options for this type of cancer are limited and in the last 20 years there have been no major developments to treat the advanced stages of this disease. Being able to recommend trabectedin for use on the NHS represents a step forward in the care of this group of patients who may have very few treatment options left.”

Roger Wilson, Director of Sarcoma UK, said: "I am delighted that trabectedin has been approved. This is the end of a challenging process for sarcoma patients and the doctors who treat them, as well as for NICE.

"This drug benefits a large proportion of the small number of patients who receive it. I have long believed that trabectedin has a significant part to play in the treatment of advanced soft tissue sarcoma. The manufacturer, PharmaMar, deserves praise for its determination to get this drug approved and it must be thanked too for its constructive approach to making the treatment accessible to patients in the UK." ( telegraph.co.uk )

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Was there a Stone Age apocalypse or not?

Was there a Stone Age apocalypse or not?. Was there a Stone Age apocalypse or not? One narrative has it that about 13,000 years ago a comet blasted North America, wiping out the continent's megafauna – as well as its early settlers.

It's a compelling story, offering a simple explanation to the mystery of why mammoths, mastodons, and Clovis humans vanished. But it's a controversial theory, and new research suggests the impact was far too small to have done any serious damage.

Doubts centre on the speed of extinctions, the fate of the Clovis culture, and the presence of supposed impact signatures. But advocates of the comet-blast theory say they will present their own new data at the American Geophysical Union (AGU) meeting in San Francisco, where they will share the stage with sceptics.

"Nothing special happened at 12,900 years ago," says John Williams of the University of Wisconsin-Madison. His data, reported in Science this week, suggest that large mammals were already rare well before the purported impact.

Scraping the bottom

Williams and his colleagues searched layered lake-bottom deposits in Indiana and New York State for the spores of the fungus Sporormiella found in the dung of large plant-eating mammals such as mammoths and horses.

From a decline in the spore counts, they conclude that the megafauna population dropped steadily between 14,800 and 13,700 years ago, making them rare 800 years before any comet strike. Williams says the data rule out a sudden, impact-driven extinction.

However, geologist and impact-advocate James Kennett at the University of California, Santa Barbara, calls that "a classic case of over-interpretation" because the data comes from only a small area and not from different sites across the whole of North America.

Cultural development

Some anthropologists are also unhappy and with the sudden extinction theory, taking issue with claims that an impact wiped out the Clovis people.

It's true that distinctive Clovis-style artefacts disappear and sites were abandoned at the start of a dramatic cooling event which began about 13,000 years ago called the Younger Dryas. But the people didn't die, says Vance Holliday of the University of Arizona in Tucson. "An artefact style was replaced by another style. You see that all over the world." Moreover, early North Americans were highly mobile hunter-gatherers who occupied sites only briefly before moving on.

What's more, the geological layer representing the Younger Dryas is missing the sort of extraterrestrial material that was a hallmark of the impact that wiped out the dinosaurs.

Comet conundrum

Isotope geochemist Mukul Sharma of Dartmouth College in Hanover, New Hampshire, says he has been unable to find any significant amount of platinum-group elements with the distinctive isotopic signature showing that they came from space. Sharma will detail his findings at the AGU meeting.

Yet something did crash into the Pacific Ocean around the period in question. In a separate AGU paper, Sharma will report finding traces of extraterrestrial osmium on the floor of the mid-Pacific dating from between 16,000 and 8000 years ago.

Some Younger Dryas deposits do contain residues similar to those from the 1908 Tunguska explosion over Siberia, says Adrian Melott of the University of Kansas, Lawrence. He reckons the North American event was "something maybe a couple of orders of magnitude bigger than Tunguska" – but still perhaps only one-hundredth the scale of the proposed comet blast. ( cientist.com )

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Water found in lunar impact probably came from comets

Water found in lunar impact probably came from comets. The mystery of where the moon's water came from may soon be solved. Evidence from NASA's LCROSS mission suggests much of it was delivered by comets rather than forming on the surface through an interaction with the solar wind.

In October, the mission crashed two impactors – a spent rocket stage and a few minutes later, the LCROSS spacecraft itself – into a crater near the moon's south pole. The spacecraft snapped images and took spectra of lunar debris kicked up by the rocket's impact and found that it contained the unmistakable signs of water.

Previous missions have also found hints of lunar water but its source has not been clear. One idea is that it forms when hydrogen atoms from the solar wind latch onto oxygen atoms in the lunar soil, creating hydroxyl and water.

But now, the evidence is mounting in favour of an alternative explanation – comet impacts. The data was discussed this week at the Lunar Exploration Analysis Group meeting, a gathering of 160 lunar scientists in Houston, Texas.

'Dirty iceballs'

The first line of evidence comes from compounds that vaporise readily, called volatiles. LCROSS found spectral signs of volatiles containing carbon and hydrogen – likely methane and ethanol – as well as others such as ammonia and carbon dioxide. "It appears that we impacted into a very volatile-rich area," LCROSS principal scientist Tony Colaprete told the conference.

These compounds should have been mostly lost to space billions of years ago, when the moon coalesced from the debris of an impact between the Earth and a Mars-sized object. Water formed through an interaction with the solar wind would therefore be relatively pure – and free of volatiles.

But comets, which are thought to have been responsible for many of the moon's impact scars, are "dirty iceballs" known to contain volatiles such as methane. "If you can nail down the source of the water [on the moon], that could tell us a lot about the cometary history of the moon for the last couple of billion years," says Larry Taylor of the University of Tennessee.

High concentrations

The second line of evidence pointing to comets comes from the amount of water detected. The solar wind is expected to form water in minute amounts, amounting to concentrations of no more than 1 per cent in the lunar soil.

LCROSS team members are still analysing the data, but calculations suggest the concentration of water is higher than that. "The data are consistent with a total hydrogen content in the range of several per cent," says Colaprete.

Beyond their link to comets, volatiles generated excitement at the meeting because of their value as a resource for human spaceflight. While water is important for survival on the moon, it is the water's hydrogen that can be used as rocket propellant.

The possibility of finding compounds like ethanol and methane, which can be used as fuel directly, makes the economic case for returning astronauts to the moon even sweeter. "LCROSS has given us our ticket back to the moon," says Noah Petro of NASA's Goddard Space Flight Center in Greenbelt, Maryland. ( Scientist.com )

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Frankenstein' fix lets asteroid mission cheat death

Frankenstein' fix lets asteroid mission cheat death. The beleaguered Hayabusa asteroid probe is back on track to return to Earth after a clever workaround coaxed one of its ion engines back to life.

The recovery is yet another reversal of fortune for the Japanese spacecraft, which has been plagued with problems since its visit to asteroid Itokawa in 2005.

It landed on the asteroid twice in November of that year, but its pellet gun – designed to dislodge material for collection – failed to fire. After an episode where it spun out of control and temporarily lost contact with Earth, engineers regained control and set it on a course back home.

Scientists are still eager to see the spacecraft return to Earth in case some loose asteroid bits accidentally made their way into the collection chamber during the landings.

But Hayabusa has been hobbling home without the full use of its four ion engines, which ionise xenon gas and then use electric fields to accelerate the ions, providing a steady – though weak – thrust.

One engine broke down shortly after launch and a second quit in 2007. When a third gave up the ghost on 4 November, it looked like Hayabusa would have too little power to ever get home.

Charge buildup

But the mission team has now cobbled together another working engine using parts from two sick ones, the Japan Aerospace Exploration Agency (JAXA) announced on Thursday.

One engine is still able to spit out positive ions for thrust, but can no longer squirt out negatively charged electrons, a step needed to prevent electric charge buildup on the spacecraft. The team got around this by spewing the required electrons from a second sick engine that retains this ability.

Now that Hayabusa in effect has two working ion engines again, it is back on track to return to Earth in June 2010, as had been planned before the 4 November glitch, JAXA says. If all goes well, it will drop its sample capsule in the Australian outback.

But Hayabusa project manager Jun'ichiro Kawaguchi of JAXA cautions that no one knows how long the cobbled-together engine will last. "This new configuration is very new to us and we are not sure ... how much we can count on [it]," ( Scientist.com )

READ MORE - Frankenstein' fix lets asteroid mission cheat death

Greenland ice loss behind a sixth of sea-level rise

GREENLAND lost 1500 cubic kilometres of ice between 2000 and 2008, making it responsible for one-sixth of global sea-level rise. Even worse, there are signs that the rate of ice loss is increasing.

Michiel van den Broeke of Utrecht University in the Netherlands and colleagues began by modelling the difference in annual snowfall and snowmelt in Greenland between 2003 and 2008 to reveal the net ice loss for each year. They then compared each year's loss with that calculated from readings by the GRACE satellite, which "weighs" the ice sheet by measuring its gravity.

The team found that results from the two methods roughly matched and showed that Greenland is losing enough ice to contribute on average 0.46 millimetres per year to global sea-level rise. The loss may be accelerating: since 2006, warm summers have caused levels to rise by 0.75 millimetres per year, though van den Broeke says we can't be sure whether this trend will continue (Science, DOI: 10.1126/science.1178176). Sea levels are rising globally by 3 millimetres on average.

Half the ice was lost through melting and half through glaciers sliding faster into the oceans, the team says. "The study gives us a really good handle on how to approximate how much ice Greenland is going to lose in the coming century," says Ted Scambos of the US National Snow and Ice Data Center in Boulder, Colorado. ( scientist.com )

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The 16 Ships Create As Much Pollution As All Cars in The World

The 16 Ships Create As Much Pollution As All Cars in The World - Last week it was revealed that 54 oil tankers are anchored off the coast of Britain, refusing to unload their fuel until prices have risen.

But that is not the only scandal in the shipping world. Today award-winning science writer Fred Pearce – environmental consultant to New Scientist and author of Confessions Of An Eco Sinner – reveals that the super-ships that keep the West in everything from Christmas gifts to computers pump out killer chemicals linked to thousands of deaths because of the filthy fuel they use.

Waiting game: Tankers moored off Devon waiting for oil prices to rise even further

We've all noticed it. The filthy black smoke kicked out by funnels on cross-Channel ferries, cruise liners, container ships, oil tankers and even tugboats. It looks foul, and leaves a brown haze across ports and shipping lanes. But what hasn’t been clear until now is that it is also a major killer, probably causing thousands of deaths in Britain alone.

As ships get bigger, the pollution is getting worse. The most staggering statistic of all is that just 16 of the world’s largest ships can produce as much lung-clogging sulphur pollution as all the world’s cars.

Because of their colossal engines, each as heavy as a small ship, these super-vessels use as much fuel as small power stations. But, unlike power stations or cars, they can burn the cheapest, filthiest, high-sulphur fuel: the thick residues left behind in refineries after the lighter liquids have been taken. The stuff nobody on land is allowed to use.

Thanks to decisions taken in London by the body that polices world shipping, this pollution could kill as many as a million more people in the coming decade – even though a simple change in the rules could stop it. There are now an estimated 100,000 ships on the seas, and the fleet is growing fast as goods are ferried in vast quantities from Asian industrial powerhouses to consumers in Europe and North America.

The recession has barely dented the trade. This Christmas, most of our presents will have come by super-ship from the Far East; ships such as the Emma Maersk and her seven sisters Evelyn, Eugen, Estelle, Ebba, Eleonora, Elly and Edith Maersk. Each is a quarter of a mile long and can carry up to 14,000 full-size containers on their regular routes from China to Europe.

Emma – dubbed SS Santa by the media – brought Christmas presents to Europe in October and is now en route from Algeciras in Spain to Yantian in southern China, carrying containers full of our waste paper, plastic and electronics for recycling.

But it burns marine heavy fuel, or ‘bunker fuel’, which leaves behind a trail of potentially lethal chemicals: sulphur and smoke that have been linked to breathing problems, inflammation, cancer and heart disease.

James Corbett, of the University of Delaware, is an authority on ship emissions. He calculates a worldwide death toll of about 64,000 a year, of which 27,000 are in Europe. Britain is one of the worst-hit countries, with about 2,000 deaths from funnel fumes. Corbett predicts the global figure will rise to 87,000 deaths a year by 2012.

Part of the blame for this international scandal lies close to home. In London, on the south bank of the Thames looking across at the Houses of Parliament, is the International Maritime Organisation, the UN body that polices the world’s shipping.

For decades, the IMO has rebuffed calls to clean up ship pollution. As a result, while it has long since been illegal to belch black, sulphur-laden smoke from power-station chimneys or lorry exhausts, shipping has kept its licence to pollute.

For 31 years, the IMO has operated a policy agreed by the 169 governments that make up the organisation which allows most ships to burn bunker fuel.

Christian Eyde Moller, boss of the DK shipping company in Rotterdam, recently described this as ‘just waste oil, basically what is left over after all the cleaner fuels have been extracted from crude oil. It’s tar, the same as asphalt. It’s the cheapest and dirtiest fuel in the world’.

Bunker fuel is also thick with sulphur. IMO rules allow ships to burn fuel containing up to 4.5 per cent sulphur. That is 4,500 times more than is allowed in car fuel in
the European Union. The sulphur comes out of ship funnels as tiny particles, and it is these that get deep into lungs.

Thanks to the IMO’s rules, the largest ships can each emit as much as 5,000 tons of sulphur in a year – the same as 50million typical cars, each emitting an average of 100 grams of sulphur a year.

With an estimated 800million cars driving around the planet, that means 16 super-ships can emit as much sulphur as the world fleet of cars.

A year ago, the IMO belatedly decided to clean up its act. It said shipping fuel should not contain more than 3.5 per cent sulphur by 2012 and eventually must come down to 0.5 per cent. This lower figure could halve the deaths, says Corbett.

It should not be hard to do. There is no reason ship engines cannot run on clean fuel, like cars. But, away from a handful of low-sulphur zones, including the English Channel and North Sea, the IMO gave shipping lines a staggering 12 years to make the switch. And, even then, it will depend on a final ‘feasibility review’ in 2018.

In the meantime, according to Corbett’s figures, nearly one million more people will die.

Smoke and sulphur are not the only threats from ships’ funnels. Every year they are also belching out almost one billion tons of carbon dioxide. Ships are as big a contributor to global warming as aircraft – but have had much less attention from environmentalists.

Both international shipping and aviation are exempt from the Kyoto Protocol rules on cutting carbon emissions. But green pressure is having its effect on airlines. Ahead of next month’s Copenhagen climate talks, airlines have promised to cut emissions by 50 per cent by 2050.

But shipping companies are keeping their heads down. A meeting of the IMO in July threw out proposals from the British Chamber of Shipping, among others, to set up a carbon-trading scheme to encourage emissions reductions.

Amazingly, they pleaded poverty. Two-thirds of the world’s ships are registered in developing countries such as Panama. These are just flags of convenience, to evade tougher rules on safety and pay for sailors.

But at the IMO, governments successfully argued that ships from developing countries should not have to cut carbon emissions. IMO secretary-general Efthimios Mitropoulos insisted: ‘We are heavily and consistently engaged in the fight to protect and preserve our environment.’ Yet without limits, carbon emissions from shipping could triple by 2050.

The failure brought calls for the IMO to be stripped of its powers to control the world’s ships. Colin Whybrow, of Greenwave, a British charity set up to campaign for cleaner shipping, says: ‘The IMO is drinking in the last-chance saloon.’

Burning low-sulphur fuel won’t cut carbon emissions from ships. But there are other ways. More efficient engines could reduce emissions by 30 per cent, according to British marine consultant Robin Meech.

Cutting speed could reduce emissions by as much again. And there are even wackier ways, such as putting up giant kites to harness the wind as in the days of sailing ships. However you look at it, the super-ships are rogues on the high seas, operating under pollution standards long since banished on land; warming the planet and killing its inhabitants. Santa’s sleigh, they are not.

Robert Pedersen, of Maersk, said: ‘The sulphur content varies according to where you get your fuel. Our average sulphur content is, I believe, 2.5 per cent. It’s rather rare you get anything close to 4.5 per cent.’ He added that ‘the sulphur issue is one for the whole industry’ and that there would be a ‘huge cost implication’ to switch to cleaner fuel. ( kompas.com )

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On science and prostitution

Belle de Jour: On science and prostitution. Under the name Belle de Jour, Brooke Magnanti wrote about her experiences as a prostitute for a London escort agency, and her blog became a bestselling book, The Intimate Adventures of a London Call Girl, and a television series.

She has a master's degree in genetic epidemiology and a PhD from the University of Sheffield's department of forensic pathology.

She currently works at the Bristol Initiative for Research of Child Health and told her agent: "if New Scientist asks for an interview, I'll do it". We did ask.

In one of your early papers you established a possible link between thyroid cancer in women in Cumbria, in north-west England, and fallout from Chernobyl in Ukraine.

The trends in thyroid carcinomas in young women in north-west England show a consistent rise since the late 1980s. But our research also shows an increase in areas that didn't receive fallout from Chernobyl, so there may be multifactorial causes at work.

You've also looked at policy for the assessment of risks from organophosphates.

There are pesticides that have been banned from indoor use in the US but are legal in the European Union, which may cause developmental, emotional and possibly autistic-spectrum disorders.

We're collating the evidence and consulting experts to put forward a case to policy-makers to implement a similar ban to the one in North America.

Your colleagues have reportedly been very supportive but do you worry that the publicity around you being Belle de Jour will hinder your career?

Yes. That was the main reason for my anonymity. If I had just wanted to be a writer it probably would have been more profitable to come out sooner, but working in science is important to me.

Science was so important to you, in fact, that you worked as an escort.

Let's be frank, postdocs are not well paid - being debt-free enabled me to continue to choose science jobs I love rather than changing career.

So for you the benefits of not being in debt outweighed the dangers of prostitution?

The particular situation I was in was far less dangerous than streetwalking and paid sufficiently well that I didn't have to do it for very long. Also I met fewer men than a streetwalker would in the same period, and again that decreased the chances of a bad experience.

I trusted my instincts, and the agency was very good about vetting clients as well.

Should British PhD students be paid a proper wage, as they are in other countries?

I'm in two minds about this: if paid a wage, they may also be expected to do more teaching, which would result in the PhD taking far longer, as it does in other countries.

I had offers of PhD places both here and in the US, and chose Sheffield because it would take half the time.

You are currently writing a novel. How does being a scientist inform your writing?

Science is my main career ambition. Writing up a project is an especially satisfying pursuit, which probably puts me in a minority of scientists.

What do you say to the charge that you have glamorised prostitution?

Call girls existed long before I got into the game, and details of what that life is like were well established before I started writing about it. Implying I single-handedly turned the business around is flattering but doesn't stand much scrutiny.

There are science-based arguments to be made for legalising the sex trade: for example, it would reduce the spread of STIs such as HIV. Is this something you would support?

In the UK, prostitution itself is legal - pimping, soliciting and brothels are not. This results in a huge safety gap between call girls and streetwalkers.

Doesn't it make sense for women at all price points in the sex business to have the same protection I did, and in doing so, possibly gain the leverage over traffickers and clients they need to protect their personal and sexual health?

How were you able to conceal your identity as Belle de Jour for so long?

My anonymity was maintained the old-fashioned way: good old confusing paper trail. We set up a corporation with other people on the board.

It wasn't internet sleuthing that led to my outing: it was because I'd told someone I couldn't trust.

The papers didn't find me, not because I'm a master of subterfuge, but because they assumed I would be one of their own - not a small-time blogger. ( newscientist.com )

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Picture of Michael Jackson Shown in The Baby's Scan

Picture of Michael Jackson Shown in The Baby's Scan. It looks like an ordinary ultrasound scan, with a blurry contrast of light and shade. But to Dawn Kelley and William Hickman, it's the face of Michael Jackson.

The imaginative couple say they can clearly see the face of the late pop star when they look at the picture of their unborn baby. Mr Hickman, 29, a window cleaner, said: 'I showed my daughter Ami, who's six, and she saw it straight away, so I thought "well, if she can see it too, it's not just me seeing things".

'

Thriller: A mother and father-to-be say they can see the face of Michael Jackson staring back at them from their unborn baby's scan

Mother-of-six- Dawn, 34, went for her 20-week scan at Sunderland Royal as normal last month, but doctors could not see the foetus's stomach or diaphragm. A few weeks later she was sent to a different medical centre for a closer look.

The more powerful scanner there is normally used to examine internal organs so the images it produces are much more detailed.

Mr Hickman said: 'We were looking at the pictures again, and I just saw Jacko there.

'None of us are really Michael Jackson fans. I mean I like him, but we're not crazy about him or anything.'

Their children Chris, 16, Amanda, 15, Jason, 13, Alisha, 10, Ami-Lee, six, and Kye, four, say they can all see the singer's face in the scan photo too. But the couple won't, however, be naming the new addition to their family after Jackson - they already know they are having a girl.

Dawn, who is due to give birth to her daughter in March, said: 'I've had plenty of scans before and none of the photos have ever looked like this one. It's a bit spooky really.

'But it is my seventh child, and they say seven is a mythical number.' ( kompas,com )

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