Wednesday, February 28, 2007

Hungry ???


The newest addition to the menu at Denny's Beer Barrel Pub in Pennsylvania is one meaty monstrosity of a burger.

The Beer Barrel Main Event Charity Burger weighs in at 55.79 kilograms.

The sizable sandwich features an 36.25 kilogram beef patty, along with a pound each of lettuce, ketchup, relish, mustard and mayonnaise, 160 slices of cheese, up to five onions and 12 tomatoes.

It's topped with a couple of pounds of banana peppers and 33 pickles, then sandwiched into a 13.60 kilogram bun.

Price tag: $A481.

AP

G Wiz - Electric Car

by ALASTAIR MCKAY (30 Apr 2006) Scotland on Sunday

THERE is a map on the wall of the office of GoinGreen's offices in Southall, West London, which shows the spread of emission-free motoring. It looks like the early stages of a virus, with coloured pins marking the address of every owner of a Reva G-Wiz.

So far, the map is restricted to Greater London. The armies of pins have outposts as far as Chislehurst and Beckenham in the south-east, and Wimbledon in the south-west, stretching as far north as Barnet. There are a couple in Ealing.

The big battalions are clustered in the leafier parts of north London, with high concentrations of colour in Primrose Hill and Hampstead. One of those pins is said to belong to Jonathan Ross - a man with a penchant for eccentric vehicles. Since they went on sale in summer 2004, more than 500 of these impish electric cars have been sold.

The analogy with a virus is apt. GoinGreen doesn't advertise its cars, instead selling them by word of mouth and through its website: www.goingreen.co.uk If the pins clump together, it's because the owners tend to recommend them to their friends. But the company did get a burst of publicity this week when the Conservative leader, David Cameron, posed with a G-Wiz (though the pistachio-tie-wearing politician actually drives a not very green Lexus GS 450).

It's to that same blue G-Wiz (reg: YK53 GOE) that I am led for my test-drive. The experience is made even more testing by the presence in the car of Graham, the photographer, and my guide, Joe Byars of GoinGreen. The G-Wiz is designed to seat two adults and two small children. It can take three tall men, but not without one of them doing an unseemly yoga position in the rear. And though the cabin is tall and the road position is quite high, the roof is no respecter of a gentleman's quiff.

The G-Wiz was conceived in California by Dr Lon Bell, an engineer who made his fortune making airbag sensors and seatbelt tensioners, before becoming intrigued by the way cars work.

In designing an electric car, he decided to ignore the assumptions of conventional construction. His first thought was to ask what was necessary in a car, from which he concluded that it needed wheels, with tyres, something to steer and a windscreen. Most of the rest was luxury and got in the way of making a nimble, no-frills electric vehicle for non-polluting urban travel.
As well as a body made from dent-resistant plastic, it has regenerative brakes: pressing the pedal works like a dynamo, recharging the engine.

It also has climate-controlled seating. Each seat has tiny heat-releasing holes which warm the body rather than the air in the car. There is a conventional heater, too, but using it will knock 10 miles from the car's 40-mile range.

Before we set off for the bright lights of Hayes, Joe flips open the bonnet to reveal a bottle containing windscreen fluid, and a small storage space. And that, more or less, is that. To the non-mechanically-minded, the G-Wiz is a remarkable piece of technology. It requires only a little more attention than a mobile phone, and it doesn't make an irritating noise in the cinema. To charge it, you stick a lead in the socket where the petrol cap should be, and you have to water the battery every two or three weeks. "It's like a plant," Joe says. "Every so often a light will come on saying 'Water me, please'."

This procedure is simpler then topping up a steam iron. You don't have to open the bonnet. You stick a small pipe into a hole by the plug, hold it in the air and pour in distilled water. You need never touch an oil can. Oiling is done during servicing. "You water your car," says Joe. "That's all you need to do."

Driving the thing is marginally more complicated, but will not test the aptitude of anyone who has ever sat in a dodgem. There are two pedals - an accelerator and a brake. The handbrake is a twisty device under the dashboard on the left of the steering wheel. The ignition is on the right.

This is the first big shock. When you turn on the engine, nothing happens. Actually, that's the point. There is no engine. When you turn the key you are not greeted by an angry growl of machinery. There is nothing, unless you count the flickering of a small green light on the dashboard. At first, this is disconcerting. Without the engine noise, the instincts of conventional driving don't kick in.

There is no pumping of the accelerator or gentle easing of the brake, and none of the sense of power which it is at the root of all car advertising. In this little moment of uncertainty, with no rush of testosterone to the places that make urban motoring slightly less relaxing than bare-knuckle boxing, it's tempting to forget the routines of driving - the mirror, signal, manoeuvre bit. Fortunately, such disorientation is not that dangerous. The G-Wiz seems to think before it moves, and when it does, it's a stately glide.

There are no gears. The car has a dial, with four modes: reverse, neutral, economy, and full power. In London, where the average speed of travel is less than 10mph, full power (with a top speed of 42mph) is rarely necessary, but it does offer slightly more oomph when easing from traffic lights.

On the open road, there is a perplexing absence of noise. Suddenly, you are aware of the volume from other cars' engines. Aurally, it's a bit like being a non-smoker in a cigar bar: you find yourself defined by the thing you are not doing. But it does make you wonder how much quieter our cities would be if all the short journeys were electric.

The car is cute in the way that Del Trotter's Reliant Robin was, and its green credentials are impeccable. But it is economically attractive, too. The G-Wiz is exempt from road tax, as it produces no carbon emissions. Since it costs only 40p to charge the car for 40 miles of driving, GoinGreen calculates that a London commuter will save the cost of the car (£7,799 with free leather seats, worth £500) in a year.

The biggest problem for the spread of the technology is the need for off-street parking during the recharging process. Some London car parks offer recharging facilities, but flat-dwellers or owners without a driveway will need support from councils to make the G-Wiz a practical option.

Similarly, potential drivers outside London will have to wait until the company expands, or the technology becomes more universal, as servicing is currently only available at GoinGreen's headquarters. How does it feel? Well, not sexy exactly, but there is something endearing about the car that seems to bring out the best in other road users.

Thanks to the demands of the yogic photographer, Graham, I was forced to drive the G-Wiz in an irregular manner, circling the circumference of a roundabout 10 times, stopping in front of a bus, reversing in the wrong direction down a one-way street, and the reaction from other road users and pedestrians was one of tickled tolerance. Even White Van Man was smiling.

Lon Bell has compared the G-Wiz to the early mobile phones. In later models the batteries will be smaller and more efficient. A prototype of a hard-top roadster already exists: it goes at 80mph and has a range of 100 miles. That may bring more torque to the electric revolution, but it will be hard-pushed to replicate the Postman Pattish charm of the little G-Wiz.

Thursday, February 22, 2007

The Economics of Climate Change

By Jonas Hagen
UN Cronicle online

The Stern Review concludes that the cost of acting to decrease global emissions of greenhouse gases is far less than the cost of dealing with the effects of climate change if no mitigation efforts are made.

However, Mr. Stern warned that "even if we are sensible about climate change and get the emissions down, the climate is going to change still more than it has".

While the world was currently experiencing the effects of an increase in global temperatures of 0.7 degrees Celsius, he said that "even if we act strongly to decrease emissions, we've got another 1.5 to 2.0 degrees centigrade to come. So we've seen maybe a quarter or a third of temperature increase we're going to have to cope with. St. Petersburg, New York, London, Cairo, Cape Town, Shanghai, Bombay, Calcutta, Dhaka-they're all under threat from sea-level rise, and many parts of the world will be under threat from hurricanes, typhoons, droughts and floods."

Mr. Stern also warned that the heatwaves that killed thousands of people in Europe in 2003 "will probably be standard by the time we get to 2050", and the Nile river, which ten countries depend on, could drop to one half of current water levels in the second half of this century.

However, the "business as usual" scenario-where no action is taken to reduce emissions- would lead to changes in the earth's climate, he said, "that we don't really understand, absolutely unprecedented and earth-transforming--the difference between where we are now and the last ice age".

Climate change also highlights global inequities, according to Mr. Stern. "All countries in the world will be affected; we're all in this together, but it is the poor that will be hit earliest and hardest. You just have to look at the effects of Katrina in New Orleans, or the effects of the typhoon that hit Bombay a couple of years ago [in July 2005]."

Global security is affected by climate change and "could cause conflict within and across countries", he said, adding that most African leaders he met with at the African Union Summit in Addis Ababa in January 2007 attributed the humanitarian crisis in Darfur to the climate problem-pushed out of their traditional lands by drought, and pastoralists were forced to move and came into conflict with settled farmers.

To reduce emissions, Mr. Stern suggested a range of solutions, which included taxes on emission-producing activities, the development and deployment of low-emission technologies, investing in energy efficiency, and preserving forests around the world.

Time is of the essence, he said. "Even though this is a long-term problem, we've got to start now. We've left it very late. If we had gotten our heads around this problem 20 years ago, it would have been much simpler and much cheaper. If we wait another 20 years, it will be still more difficult and expensive."

Rich countries must take responsibility for a problem they have caused, Mr. Stern said, suggesting emission reductions of 60 to 80 per cent for developed nations. He noted that France had set the goal of a 75 per cent reduction by 2050, the United Kingdom at 60 per cent and the State of California in the United States aimed at 80 per cent.

Developing countries, he added, must understand that they can continue to expand their economies and achieve progress on the Millennium Development Goals-eight targets for human development that UN Member States agreed upon to reach by 2015.

Mr. Stern cited the progressive policy in China, which is "reforesting, not deforesting". The country hoped to make energy production 20 per cent more efficient as part of its 11th five-year plan, which is already underway, he reported, adding that an $8,000 tax was established on sports utility vehicles (SUVs) in Beijing.

"I'm much more optimistic six or nine months ago about where the world is moving", he said.

He called on the international community to "act strongly and on the right kind of scale", stating further that the United Nations is "a place we can really take that forward in a very powerful way".

Mr. Sachs agreed that "we have to move quickly and urgently on this issue. That means setting in place a full century of transition, with much of the transition being completed by 2050."

Some 40 or 50 years from today, energy sources should be very different from what they are today, he said. Supplying significant amounts of energy from nuclear power and coal-fired plants that used carbon sequestration technology, where carbon produced by the burning coal is pumped back into the earth, is "within reach", he noted.

Such plants must be built quickly in China or India, in order to see if they are viable as sources of clean energy. "Once those plants are done, everything is going to become a lot clearer and less hypothetical than it is now", Mr. Sachs pointed out.

Wednesday, February 21, 2007

The Changing Climate on Climate Change

by Joseph E. Stiglitz

The message, it seems, has finally gotten through: global warming represents a serious threat to our planet. At the recent World Economic Forum in Davos, world leaders saw climate change, for the first time, topping the list of global concerns.

Europe and Japan have shown their commitment to reduce global warming by imposing costs on themselves and their producers, even if it places them at a competitive disadvantage. The biggest obstacle until now has been the United States. The Clinton administration had called for bold action as far back as 1993, proposing what was in effect a tax on carbon emissions; but an alliance of polluters, led by the coal, oil, and auto industries beat back this initiative.

To the scientific community, the evidence on climate change has, of course, been overwhelming for more than a decade and a half. I participated in the second assessment of the scientific evidence conducted by the Intergovernmental Panel on Climate Change, which perhaps made one critical mistake: it underestimated the pace at which global warming was occurring. The Fourth Assessment, which was just issued, confirms the mounting evidence and the increasing conviction that global warming is the result of the increase in greenhouse gases in the atmosphere.

The increased pace of warming reflects the impact of complex non-linear factors and a variety of “tipping points” that can result in acceleration of the process. For instance, as the Arctic ice cap melts, less sunlight is reflected. Seemingly dramatic changes in weather patterns including the melting of glaciers in Greenland and the thawing of the Siberian permafrost have at last convinced most business leaders that the time for action is now.

Recently, even President Bush seems to have woken up. But a closer look at what he is doing, and not doing, shows clearly that he has mostly heard the call of his campaign contributors from the oil and coal industries, and that he has once again put their interests over the global interest in reducing emissions. If he were truly concerned about global warming, how could he have endorsed the construction of coal-fired electricity plants, even if those plants use more efficient technologies than have been employed in the past?

What is required, first and foremost, are market-based incentives to induce Americans to use less energy and to produce more energy in ways that emit less carbon. But Bush has neither eliminated massive subsidies to the oil industry (though, fortunately, the Democratic Congress may take action) nor provided adequate incentives for conservation. Even his call for energy independence should be seen for what it is a new rationale for old corporate subsidies.

A policy that entails draining America’s limited oil supplies I call it “drain America first” will leave the US even more dependent on foreign oil. The US imposes a tariff of more than 50 cents per gallon on sugar-based ethanol from Brazil, but subsidizes inefficient corn-based American ethanol heavily indeed , it requires more than a gallon of gasoline to fertilize, harvest, transport, process, and distill corn to yield one gallon of ethanol.

As the world’s largest polluter, accounting for roughly a quarter of global carbon emissions, America’s reluctance to do more is perhaps understandable, if not forgivable. But claims by Bush that America cannot afford to do anything about global warming ring hollow: other advanced industrial countries with comparable standards of living emit only a fraction of what the US emits per dollar of GDP.

As a result, American firms with access to cheap energy are given a big competitive advantage over firms in Europe and elsewhere. Some in Europe worry that stringent action on global warming may be counterproductive: energy-intensive industries may simply move to the US or other countries that pay little attention to emissions. And there is more than a grain of truth to these concerns.

A striking fact about climate change is that there is little overlap between the countries that are most vulnerable to its effects mainly poor countries in the South that can ill afford to deal with the consequences and the countries, like the US, that are the largest polluters. What is at stake is in part a moral issue, a matter of global social justice.

The Kyoto Protocol represented the international community’s attempt to begin to deal with global warming in a fair and efficient way. But it left out a majority of the sources of emissions, and unless something is done to include the US and the developing countries in a meaningful way, it will be little more than a symbolic gesture. There needs to be a new “coalition of the willing,” this time perhaps led by Europe and this time directed at a real danger.

This “coalition of the willing” could agree to certain basic standards: to forego building coal-fired plants, increase automobiles’ fuel efficiency, and provide targeted assistance to developing countries to enhance their energy efficiency and reduce emissions. Coalition members could also agree to provide stronger incentives to their own producers, through either more stringent caps on emissions or higher taxes on pollution. They could then agree to impose taxes on products from other countries including the US that are produced in ways that unnecessarily add substantially to global warming. What is at stake is not protecting domestic producers, but protecting our planet.

The changing climate on climate change provides political leaders in Europe and other potential members of this “coalition of the willing” an unprecedented opportunity to move beyond mere rhetoric. The time to act is now.

Joseph E. Stiglitz, a Nobel laureate in economics, is Professor of Economics at Columbia University and was Chairman of the Council of Economic Advisers to President Clinton and Chief Economist and Senior Vice President at the World Bank. His latest book is Making Globalization Work.

Sunday, February 18, 2007

Remote Control Inventor dies

February 17, 2007
SMH

Hit the mute button for a moment of silence: The co-inventor of the TV remote, Robert Adler, has died.

Adler, who won an Emmy Award along with fellow engineer Eugene Polley for the device, died yesterday of heart failure at a Boise nursing home at 93, Zenith Electronics Corp said today.

In his six-decade career with Zenith, Adler was a prolific inventor, earning more than 180 US patents. He was best known for his 1956 Zenith Space Command remote control, which helped make TV a truly sedentary pastime.

In a May 2004 interview, Adler recalled being among two dozen engineers at Zenith given the mission to find a new way for television viewers to change channels without getting out of their chairs or tripping over a cable.

But he downplayed his role when asked if he felt his invention helped raise a new generation of people too lazy to get off the couch.

"People ask me all the time - 'Don't you feel guilty for it?' And I say that's ridiculous," he said. "It seems reasonable and rational to control the TV from where you normally sit and watch television."

Various sources have credited either Polley, another Zenith engineer, or Adler as the inventor of the device. Polley created the "Flashmatic," a wireless remote introduced in 1955 that operated on photo cells. Adler introduced ultrasonics, or high-frequency sound, to make the device more efficient in 1956.

Zenith credits them as co-inventors, and the National Academy of Television Arts and Sciences awarded both Adler and Polley an Emmy in 1997 for the landmark invention.

"He was part of a project that changed the world," Polley said from his home in Lombard, Illinois.

Adler joined Zenith's research division in 1941 after earning a doctorate in physics from the University of Vienna. He retired as research vice president in 1979, and served as a technical consultant until 1999, when Zenith merged with LG Electronics Inc.

During World War II, Adler specialised in military communications equipment. He later helped develop sensitive amplifiers for ultra high frequency signals used by radio astronomers and by the US Air Force for long-range missile detection.

Adler also was considered a pioneer in SAW technology, or surface acoustic waves, in colour television sets and touch screens. The technology has also been used in cellular telephones.

The US Patent and Trademark Office published his most recent patent application, for advances in touch screen technology, on Feb. 1.

His wife, Ingrid, said Adler would not have chosen the remote control as his favourite invention. In fact, he did not even watch much television.

"He was more of a reader," she said. "He was a man who would dream in the night and wake up and say, 'I just solved a problem.' He was always thinking science."

AP

Big donation for environmental studies centre


pic: Yahoo founder Jerry Yang.

February 16, 2007
SMH

Jerry Yang, co-founder of internet media company Yahoo, is donating $US75 million ($A96m) to Stanford University, which will spend most of the money on a new environmental studies center, the university said on Thursday.

Yang, who started Yahoo in 1994 with fellow student David Filo while working on his doctorate, planned to make the donations over a period of several years, said Howard Pearson, director of Stanford's development office.

It will be the largest of several donations Yang has made to his alma mater, although Pearson declined to say how much he has previously given.

Yang would make the donations with his wife, Akiko Yamazaki, also a Stanford graduate.

Of the total, $US50 million will pay for a new environment and energy building and $US5 million will go toward a doctor training facility for Stanford's medical school.

The remaining $US20 million will be used for future projects, Stanford said.

Yang's net worth was estimated at $US2.4 billion in 2006, according to a report in Forbes magazine last September.

Stanford received $US911 million in alumni donations in its fiscal year ended August 31, up more than 50 percent from the $US603 million the previous year.

Although Yang obtained both bachelor's and master's degrees from Stanford, he never completed his doctorate in electrical engineering, and his biography on Yahoo says he "is currently on a leave of absence" from the program.

Reuters

Bionic eye

Peter Weekes
February 18, 2007

MELBOURNE'S Eye and Ear Hospital will start implanting bionic eyes that restore sight to the blind within a few years.

The hospital is one of three centres outside the United States that have been chosen to implant the revolutionary device developed by the Doheny Eye Institute at the University of Southern California.

American scientists said last week that the first six patients to try the bionic eye had learnt how to detect light, distinguish between objects and perceive direction of motion.

"We expected that all they would be able to do would be to differentiate between light and dark.

But we were amazed to find that they can tell the difference between objects such as a plate, a knife and a cup, and tell which way people are moving," said Professor Mark Humayun of the University of California, who led the research.

His team is preparing to test a more advanced version of the implant on as many as 75 patients.

"If the new trial hits its milestones, the second-generation implant could be commercially available in two years," Professor Humayun said.

The device offers hope to millions of people who have lost their vision to retinitis pigmentosa, a group of inherited eye diseases that cause the degeneration of the photoreceptor cells that capture and process light. It is the most common cause of blindness among those under 50.

The implant is not suitable for every form of blindness, but scientists hope that it might be used to restore the sight of those with degenerative eye diseases, particularly those with macular degeneration who are over 75.

Professor William Campbell, head of the Royal Victorian Eye and Ear Hospital's vitro retinal unit, described the device as "the beginning of a very exciting development in opthamology".

"We have been chosen to be one of the centres around the world where they want to put in their implants, but it will be two or three years before we start doing it. We will be putting some of the early models in when we find suitable candidates and after we have been trained."

The device comes in two parts. A tiny camera in the lens or on the bridge of a pair of lightweight glasses captures images.

This information is transmitted to a radio receiver implanted behind the patient's ear that converts it to electrical signals, which are sent to a grid of electrodes implanted in the retina.

These electrodes stimulate retinal nerve cells to produce electrical impulses that send signals to the brain so the patient can see spots of light in different patterns.

While the first-generation device had 16 electrodes, the new one has 60 electrodes and will cost about $32,000.

The first device took 16 years of research, but the second version has taken just four years.

Source: The Sun-Herald

Friday, February 16, 2007

Shark-wrestling Phil




Jane Holroyd
February 16, 2007
SMH

A South Australian man who wrestled and killed a 1.3-metre shark on Wednesday has been described as a "risk taker" by his wife.

Phillip Kerkhof, 41, jumped into shallow waters to chase the bronze whaler shark because it was eating bait that he and other fisherman were using off a jetty near Port Lincoln.

Mr Kerkhof wrestled the shark after capturing it in his arms and managed to fling it up onto the jetty before killing it.

His wife Christine said Phillip, a bricklayer, had nine lives.

"Just after we got married he fell off a 100-foot weir and did not even go to hospital," she told theage.com.au.

Mrs Kerkhof said she was at home on Wednesday when her husband arrived at their Louth Bay home with the shark.

"When he brought it home he called, 'Come out here! Come outside!' I walked outside and there's a shark on the lawn. I just shook my head because I'm used to my husband doing crazy things.

"He didn't think," Mrs Kerkhof said. "He'd had a few vodkas and wasn't thinking straight. He just does things off impulse. He thought about it later and said, 'That was a bit dangerous.'"

Wednesday, February 14, 2007

The Stranger Within (Human Chimeras)

New Scientist vol 180 issue 2421
15 November 2003, page 34

Human chimeras were once thought to be so rare as to be just a curiosity.

But there's a little bit of someone else in all of us, says Claire
Ainsworth, and sometimes much more...

EXPLAIN this. You are a doctor and one of your patients, a 52-year- old woman, comes to see you, very upset. Tests have revealed something unbelievable about two of her three grown-up sons. Although
she conceived them naturally with her husband, who is definitely
their father, the tests say she isn't their biological mother.
Somehow she has given birth to somebody else's children.

This isn't a trick question - it's a genuine case that Margot Kruskall, a doctor at the Beth Israel Deaconess Medical Center in Boston, Massachusetts, was faced with five years ago. The patient, who we will call Jane, needed a kidney transplant, and so her family underwent blood tests to see if any of them would make a suitable donor. When the results came back, Jane was hoping for good news.

Instead she received a hammer blow. The letter told her outright that
two of her three sons could not be hers. What was going on?

It took Kruskall and her team two years to crack the riddle. In the end they discovered that Jane is a chimera, a mixture of two individuals - non-identical twin sisters - who fused in the womb and grew into a single body. Some parts of her are derived from one twin, others from the other.

It seems bizarre that this can happen at all, but Jane's is not an
isolated case. Around 30 similar instances of chimerism have been
reported, and there are probably many more out there who will never
discover their unusual origins.

While cases like Jane's are the extreme, researchers now think that
there's a little bit of chimera in all of us, and what was once seen
as a biological oddity may serve a vital function. We may owe our
lives to being chimeras.

At first, Jane's case had Kruskall completely puzzled. The original
data came from the tests done to "tissue-type" her and her children.
Such tests are based on a set of genes called the HLA complex, which
encode many different immune proteins, including cell surface proteins that immune cells use to distinguish the body's own tissues
from foreign material. There are hundreds of different versions, or
alleles, of each HLA gene, and because of this, each person's
combination of alleles is almost unique. But because the genes are
clustered close together on chromosome 6, they tend to be inherited
together in a block known as a haplotype. Everyone inherits two HLA
haplotypes, one from each parent.

Transplant doctors know that the closer the match between two people's HLA haplotypes, the lower the risk of a transplant between them being rejected. If you need a transplant, the obvious place to look for people with a similar haplotype is your close family. Your siblings, for example, have a 1-in-4 chance of matching yours exactly, while your children will have at least 50 per cent of your HLA genes.

Confronted with Jane's bizarre test results, Kruskall's team's first line of enquiry was to take another look at Jane's HLA genes and those of her immediate family. They identified Jane's haplotypes and dubbed them 1 and 3. They tested Jane's husband too - he had types 5 and 6. And when they looked at her sons they confirmed that the original tissue-typing was correct. While all three shared a haplotype with their father, only one shared one of Jane's. The other two sons had a haplotype of unknown origin, labelled type 2.

The obvious interpretation was that Jane was not the biological
mother of two of her sons, yet they were all conceived naturally,
so how could this be? One possibility was that both boys were
accidentally swapped at birth, but the chance of this happening twice to the same family is very small. Add in the fact that both sons share a haplotype with their father and it becomes a near impossibility.

Stumped, Kruskall sent her data out to colleagues, asking them if
they could make sense of it. Soon researchers around the world were
scratching their heads in bewilderment. "I did get the most amazing
set of explanations," Kruskall recalls. "No one could quite figure it
out." One suggested that Jane had secretly undergone fertility
treatment using donated eggs. Another speculated that Jane and her
husband had got her sister to conceive children with his sperm, and
then pretended they were hers.

The breakthrough came when Kruskall's team checked the HLA haplotypes of other members of Jane's family who had been omitted from the original tests. They discovered that her brother carried the mystery haplotype 2 - suggesting that the two sons were related to Jane in some way after all. "That really provided the spur that kept us going," Kruskall says.

So where did the sons' odd haplotype come from? Since Jane's blood cells provided no match, the team decided to test DNA from some of her other tissues, including her thyroid gland, mouth and hair. What they discovered was astonishing. Some of her tissues carried haplotypes 1 and 3, while others contained 2 and 4 (The New England Journal of Medicine, vol 346, p 1546). Jane's body was made up of two genetically distinct types of cells.

There was only one conclusion: Jane was a mixture of two different people.

Kruskall thinks the most likely explanation for this is that Jane's mother conceived non-identical twin girls, who fused at an early stage of the pregnancy to form a single embryo. In medical parlance, Jane is a tetragametic chimera, a person whose body is made up from two genetically distinct lines of cells derived from a total of four gametes - eggs and sperm.

This instantly explains why the tissue-typing yielded such paradoxical results. For some reason, cells from only one twin have come to dominate in Jane's blood - the tissue used in tissue-typing. In Jane's other tissues, however, including her ovaries, cells of both types live amicably alongside each other, hence the apparently impossible genetics of her three sons. One came from an egg derived from the twin whose cells dominate Jane's blood, while his two brothers came from eggs derived from the other twin's cells.

Nobody knows how common tetragametic chimerism is. It often has no outward signs and those who uncover their chimeric nature do so only by accident.

Nature reported a similar case to Jane's in 1979, when genetic tests
suggested that a woman could not be the mother of any of her four
children. There had been no hint that the woman was chimeric.

Some chimeras do have unusual physical features. For example, one
girl was discovered to be a chimera because her eyes were different colours, one brown, the other hazel. Others have come to light when doctors investigated problems with their reproductive systems, and
found that they had structures from both male and female reproductive
organs as a result of having cells of both sexes in their bodies. But most probably go through life utterly unaware of their unusual constitution.

"They are probably dramatically under-diagnosed," Kruskall says, "and also dramatically rare."

Yet this kind of chimerism may still be common enough to cast doubt on the way we carry out genetic tests of parenthood. Kruskall is currently helping out with a court case where a woman is suing her partner, claiming that he is the father of her child. In a bizarre twist that would nonplus even Jerry Springer, tissue-typing tests proved he was the father, but ruled her out as the mother. The situation could be explained by chimerism in the mother, Kruskall speculates.

But what about a case where the father was a chimera? "You could imagine that you could rule out a person who is in fact the father," she says. This is especially plausible if one cell line always comes to dominate in the blood, as happened with Jane. Animal studies of chimerism suggest that this is indeed common.

What's more, the incidence of tetragametic chimerism is set to rise,
Kruskall says, because of modern fertility techniques that increase the rate of twinning. Drugs used to make a woman ovulate can cause her to release more than one egg at a time, for example, while many IVF clinics still transfer more than one embryo into the womb. And the fact that embryos are in close contact in the lab dish or when transferred to the womb may encourage them to fuse, according to a report by a team at the University of Edinburgh, UK. In 1998, they reported a case of a chimeric IVF baby who resulted from the accidental fusion of a male embryo and a female embryo (The New England Journal of Medicine, vol 338, p 166). The child was outwardly male, but the left hand side of his internal reproductive system had developed as an ovary and fallopian tube.

Meanwhile, Jane's mystery is solved - and it even has a happy ending. Because her body contains double the normal number of HLA haplotypes, it means that she has a much greater chance of finding a suitable donor kidney.

But the story doesn't end there. There is growing evidence that chimerism in one form or another may not be so unusual at all. In fact, some researchers now think that most of us, if not all, are chimeras of one kind or another. Far from being pure-bred individuals composed of a single genetic cell line, our bodies are cellular mongrels, teeming with cells from our mothers, maybe even from grandparents and siblings. This may seem a little shocking at first. The thought of playing host to cells from other people may offend your sense of individuality. But you may have those outsiders to thank for keeping you healthy.

During pregnancy, the blood of the mother and fetus are kept separate, but some cells manage to slip through, meaning that you will have picked up some cells from your mother, and she some from you. In fact, some 80 to 90 per cent of women carry their children's cells or DNA in their blood during pregnancy and up to 50 per= centcarry them for decades after giving birth, a condition called microchimerism (New Scientist, 24 April 1999, p4). If your mother then had more children, some of your cells could in principle slip back through into your younger sibling's body. And twins can end up swapping cells in the womb, especially if they share a placenta. So a single person can be a veritable menagerie of different cell types from different generations. "Women harbour cells from both their mother and their children," says J. Lee Nelson, an immunologist at the Fred Hutchinson Cancer Research Center in Seattle.

The fact that fetal cells persist in their mother's bloodstream for decades has been known since the mid 1990s. But only recently has anyone investigated how common it is for cells to move the other way – from mothers into their children. To investigate this, Nelson and her colleague Natalie Lambert have been searching for maternal cells in the blood of adult women.

In a forthcoming paper in the journal Arthritis & Rheumatism, they describe how they took blood samples from 32 healthy women and found that 22 per cent of them were carrying white blood cells from their mothers. These maternal cells were relatively rare - at most there were 50 per million blood cells - but Nelson suspects that more extensive tests of blood and other tissues such as bone marrow would reveal microchimerism in a far greater percentage of women. And the same goes for men too. "Our guess would be that it is probably universal," she says.

This discovery raises some puzzling questions. How come the invading cells don't simply get wiped out by the immune system? Do the cells divide inside their new host? And why do mother and child exchange cells at all - is it just an accident, or does it have a purpose?


In the case of fetal cells crossing to the mother, Nelson says we don't know whether it serves any specific purpose, but one important factor could be that these cells encourage the mother's immune system to tolerate her fetus. After all, pregnancy is rather like hosting a transplanted organ for nine months, and transplant researchers have known for some time that microchimerism caused by white blood cells from the transplant mixing with those of the recipient can encourage the host to accept the transplant under certain circumstances. And researchers think the breakdown of this long-term tolerance to fetal cells may be the cause of some autoimmune diseases in women (New Scientist, 24 February 2001, p 8).

"But what benefit [fetal cells] might offer long term, no one knows,"
Nelson says. As for cells passing from mother to fetus, there are hints that this may play a vital role in keeping the unborn child healthy. Your mother's cells don't just hang around passively in your body, Nelson believes. They might play an active role in repairing your tissues, especially while you are still in the womb. And she has evidence that unknown types of maternal cells cross the placenta and then "transdifferentiate" or transform themselves into different kinds of cells that then become part of the baby's body.

Anne Stevens, a researcher in Nelson's team made the discovery while
studying the bodies of babies who had died from an autoimmune disease
called neonatal lupus syndrome, which attacks heart muscle. In the course of testing the heart cells, she found that the babies' hearts contained muscle cells that could only have come from their mothers. Nelson says she can't yet be sure exactly how they got there, but thinks it likely that blood stem cells from the mother made their way to the heart of the developing fetus and transdifferentiated into heart cells. "It really is amazing," she says. "This is really the next conceptual leap in the entire field, I think."

The question is, what are these maternal cells doing? Are they the cause of the autoimmune disease in the children or are they trying to intervene? One possibility is that the presence of the maternal cells triggers the baby's immune system to attack the heart.

Mother and child usually tolerate each other, but if this were to break down, the fetus's immune system would identify the mother's cells as foreign and attack them, with the fetus's own heart cells getting caught in the crossfire.

But Nelson thinks there is another, more positive explanation. "The second possibility is that the maternal cells are there trying to repair the damaged tissue," she says. Her results don't yet tell her which explanation is correct, but she says: "I always go back to remembering that there could well be beneficial functions because [microchimerism] is so common in healthy people."

While microchimerism may force immunologists to rewrite their textbooks, it may also prod us into seeing ourselves in a new light. Rather than being isolated individuals, perhaps we should see ourselves more as a collective - an individual made of many other different individuals. On one level, you are you, a person with your own thoughts and feelings. But zoom in one level and you are a supercolony of individual cells, some cooperating, others competing. Zoom in to the level of your genome, and you find individual chromosomes and genes, all jostling to get through to the next round of natural selection. It's all a question of perspective.

Saturday, February 03, 2007

World wakes to climate calamity

Stephanie Peatling, Wendy Frew and Jo Chandler
February 3, 2007
SMH

THE world has been delivered its strongest warning yet that human actions are causing global warming and that greenhouse gas emissions must be reined in by 2020 if humanity wants a chance to avoid catastrophic climate change.

A turbulent future of violent storms, devastating drought, higher temperatures and rising sea levels is inevitable, according to the United Nations' Intergovernmental Panel on Climate Change, which released its 1200-page report in Paris last night. The work of 2500 scientists over six years, it is considered the most authoritative evaluation of climate change ever produced.

It details six scenarios under which temperatures are predicted to rise from at least 1.1 degrees and possibly as much as 6.4 degrees by 2100.

The final text of the report says it is "very likely" that human activities led by burning fossil fuels account for most of the warming in the past 50 years. It puts this at a 90 per cent certainty - a significant ramping up of the language of the last report of the panel in 2001, which said the link was "likely". Scientists at the final four-day workshop said this was the most important paragraph of the report.

"There can be no question that the increase in greenhouse gases are dominated by human activities," said the senior US Government scientist, Susan Solomon. She called the warming of the Earth "unequivocal and said greenhouse gases entering the atmosphere were not being cancelled by its normal processes.

The report provides what may be cold comfort in slightly reduced projections on rising sea levels - from 18 centimetres to 59cm by 2100, instead of 9cm to 88cm, as forecast in 2001. But there is a flat pronouncement that global warming is essentially a runaway train that cannot be stopped for hundreds of years.

Human-caused warming and rises in sea levels "would continue for centuries" because the process has already started, "even if greenhouse gas concentrations were to be stabilised", said the 21-page executive summary, which will be delivered to the world's policy makers.

"The observed widespread warming of the atmosphere and ocean, together with ice-mass loss, support the conclusion that it is extremely unlikely that global climate change of the past 50 years can be explained without external forcing, and very likely that is not due to known natural causes alone," it said.

The Australian of the Year, the scientist Tim Flannery, said the highest temperature forecasts could spell disaster for many species. "[It] lays out a sort of middle-of-the road trajectory, which is alarming enough, I can tell you, for this century," Professor Flannery said. "Three degrees will be a disaster for all life on Earth. We will lose somewhere between two out of every 10 and six out of every 10 species living on the planet at that level of warming. It will set in train a series of climate consequences that will run for a thousand years."


The forecasted temperature rise is likely to mean Australia's average temperature rises by 0.7 within the next 20 years and as much as four degrees by the end of the century, the former head of CSIRO's atmospheric research division, Graeme Pearman, said.

Other than a subsequent drop in rainfall, Professor Pearman said temperature and sea rises would have serious consequences for coastal communities.

"Australia has continued to develop more and more towards a coastal community," he said.
Building codes had not been developed that would cope with the storms expected to lash the coast in coming years. The report had depressed him, Professor Pearman said.

"We've been hoping someone would find we were wrong. It simply confirms the issue. It's the issue of whether human societies in general have the capacity to respond to a major threat like this. At the moment I'm not sure we are going to have that. I'm not sure we're going to respond in time."

The 2001 report led scientists to castigate the Australian Government for not taking urgent action six years ago.

Labor will now head into the federal election determined to stake out the green vote with a climate policy that argues the cost of doing nothing will destroy the economy and the environment.

The Minister for Environment and Water, Malcolm Turnbull, said people needed to learn how to adapt to hotter temperatures.

"We have to deal with our built environment in terms of how we deal with heat and energy efficiency and, of course, we have to use water more efficiently," Mr Turnbull said. He said meeting the Kyoto target - which allows Australia's emissions to continue to rise - was "virtuous" but would not change anything.

"Of course we should seek to reduce them [emissions], because we are committed to becoming a good global citizen," he said.

The Government is exploring an emissions trading scheme and nuclear power as part of its climate-change strategy and has already committed millions of dollars to experimental technology such as clean coal and geosequestration. But these strategies are unlikely to deliver significant reductions in emissions for several decades.

Polling by green groups shows voters see the environment as a big point of difference between the Government and the Opposition.

A meeting of Labor's shadow cabinet last week agreed to keep the former leader Kim Beazley's pledge to cut greenhouse gas emissions by half by 2050.


The Opposition has already promised to ratify the Kyoto Protocol, introduce emissions trading and boost the use of renewable energy, but it has not provided any clear timetable for how it would achieve the cuts.

"We cannot deal with the water crisis without dealing with the climate-change crisis at the same time," said the Opposition Leader, Kevin Rudd.

The CSIRO says Australia's emissions must fall 60 per cent by 2050 compared with 1990. But the latest government figures show that by the end of this decade alone, gas emissions from electricity production will have risen by half on their 1990 levels.

The president of the Australian Academy of Science, Professor Kurt Lambeck, said yesterday: "This intensive review of the past five years' scientific evidence was undertaken by hundreds of scientists worldwide and confirms what we already know - we have now lost five years that could have been used in implementing remedial actions."

At the Paris meeting, there was a last-ditch bid to water down the statement from two nations — Saudi Arabia and another unnamed country (not the US or Australia) among the 130 countries represented at the plenary. It eventually passed intact after the meeting accepted a suggestion - initiated by the small Australian delegation - to deal with the dissenting country's concerns in a footnote. It states that there are remaining uncertainties over climate change "based on current methodologies".

Other areas of disagreement were over how much sea levels would rise, and concerns about the ferocity of future cyclones, said Dr Geoff Love, head of the Australian Bureau of Meteorology and a member of the Australian team.

But he said it was not so much about the science as about the semantics in the summary.
As the report co-author Philip Mote, the Washington state climatologist, said in translating his fellow scientists' language: "We did it."

He added: "Scientists are pretty well done arguing about whether the warming in the last 50 years is related to burning fossil fuels."

Professor Flannery said: "It's our problem. We have to do something about it. We have the tools. We're so far lacking the will."

Friday, February 02, 2007

UN panel blames humans for global warming

The United Nations (UN) climate panel has agreed that human activities are causing global warming that may bring more droughts, heatwaves and rising seas, delegates say.

The panel's report, due for release tonight and bolstering conclusions from a 2001 study, may put pressure on governments and companies to do more to curb greenhouse gases mainly from burning fossil fuels in power plants, factories and cars.

Scientists and government officials in the Intergovernmental Panel on Climate Change (IPCC), the most authoritative group on global warming, agreed it was "very likely" that human activities were the main cause of warming in the past 50 years, delegates say.

In IPCC language, "very likely" means at least 90 per cent probability and is the strongest link to human activities since the IPCC was set up in 1988.

The previous study in 2001 said a link was "likely" or 66 per cent probable.

IPCC officials declined comment, saying the report will be released soon.

The IPCC, grouping 2,500 scientists from 130 countries, is also set to say that oceans will keep rising for more than 1,000 years even if governments stabilise greenhouse gas emissions.

The report is the first of four this year by the panel that will outline threats of warming.

Delegates say the Paris meeting, looking at the science of global warming, later agreed a "best estimate" that temperatures will rise by 3 degrees Celsius by 2100 over pre-industrial levels, the biggest change in a century for thousands of years.

Rain, less ice

It says bigger gains, of up to 6.3 degrees Celsius in one model, cannot be ruled out but do not fit well with other data.

The world is now about 5 degrees Celsius warmer than during the last Ice Age.

The draft accord projects that Arctic ice will shrink, and perhaps disappear in summers by 2100, while heatwaves and downpours would get more frequent.

The numbers of tropical hurricanes might decrease but the storms would become stronger.

The Gulf Stream bringing warm waters to the North Atlantic could slow, although a shutdown is highly unlikely, it says.

Sea levels are likely to rise by between 28 and 43 centimetres this century, a lower range than forecast in 2001.

Rising seas threaten low-lying Pacific islands and low-lying coastal nations from Bangladesh to the Netherlands.

"Governments planning coastal defences have to live with large uncertainties for now and quite some time in future," Professor Stefan Rahmstorf of Germany's Potsdam Institute for Climate Impact Research said.

Professor Rahmstorf wrote a report last year saying that observations of past changes indicated a bigger rise by 2100, of 50 to 140 centimetres.

The Eiffel Tower in Paris, near where the IPCC experts were meeting, was to shut off its famous night-time illuminations for five minutes on Thursday night (local time) to draw attention to energy use.

Many experts hope the IPCC report will spur stalled talks on expanding the fight against global warming.

Thirty-five industrial nations aim to cut emissions of greenhouse gases to 5 per cent below 1990 levels by 2008-12 under the UN Kyoto Protocol and want outsiders such as the United States, China and India to do more.

Last week President George W Bush said climate change was a "serious challenge".

But he has stopped short of capping emissions despite pressure from Democrats who control both houses of Congress, arguing Kyoto would damage the economy.

- Reuters

Thursday, February 01, 2007

HDP


Random Man gets visit from HDP.

Welcome PVR !!