Alzheimer's damage reversed by deep brain stimulation

BRAIN shrinkage in people with Alzheimer's disease can be reversed in some cases - by jolting the degenerating tissue with electrical impulses. Moreover, doing so reduces the cognitive decline associated with the disease.

"In Alzheimer's disease it is known that the brain shrinks, particularly the hippocampus," says Andres Lozano at Toronto Western Hospital in Ontario, Canada. What's more, brain scans show that the temporal lobe, which contains the hippocampus, and another region called the posterior cingulate use less glucose than normal, suggesting they have shut down. Both regions play an important role in memory.

To try to reverse these degenerative effects, Lozano and his team turned to deep brain stimulation - sending electrical impulses to the brain via implanted electrodes.

The group inserted electrodes into the brains of six people who had been diagnosed with Alzheimer's at least a year earlier. They placed the electrodes next to the fornix - a bundle of neurons that carries signals to and from the hippocampus - and left them there, delivering tiny pulses of electricity 130 times per second.

Follow-up tests a year later showed that the reduced use of glucose by the temporal lobe and posterior cingulate had been reversed in all six people (Annals of Neurology, DOI: 10.1002/ana.22089).

The researchers have now begun to investigate the effects on the hippocampus. At the Society for Neuroscience annual meeting in Washington DC last week they announced that while they saw hippocampal shrinking in four of the volunteers, the region grew in the remaining two participants.

"Not only did the hippocampus not shrink, it got bigger - by 5 per cent in one person and 8 per cent in the other," says Lozano. It's an "amazing" result, he adds.

Tests showed that these two individuals appeared to have better than expected cognitive function, although the other four volunteers did not.

Though Lozano is not sure exactly how the treatment works, his team's recent work in mice suggests that the electrical stimulation might drive the birth of new neurons in the brain. Deep brain stimulation in mice also triggers the production of proteins that encourage neurons to form new connections.

The researchers are now embarking on a trial involving around 50 people, but John Wesson Ashford at Stanford University, California, wonders how practical the approach will be when there are millions of people with Alzheimer's.

Lozano points out that around 90,000 people worldwide with Parkinson's disease have already received deep brain stimulation. The incidence of Alzheimer's is only five times that of Parkinson's, he says. "If it can be used in Parkinson's, it can be used in Alzheimer's."

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Kidney recipients freed from lifelong drugs

People who get a kidney transplant usually face a life sentence of drugs that suppress their immune systems – otherwise, their body will reject the new organ. A new cellular therapy could change that.

Immunosuppressant drugs can have severe side effects, increasing the risk of heart disease, infection, cancer and diabetes. So as well as saving money, dispensing with them would bring major health benefits.

Samuel Strober at Stanford University in California and colleagues seem to have worked out how to do it. Following transplant surgery, Strober's team first give patients ordinary immunosuppressive drugs, such as cyclosporine. They then apply mild radiation to the lymph nodes, spleen and thymus to further weaken the immune system. This kills some but not all of the patient's white blood cells.

They also inject antibodies which temporarily destroy the patient's most aggressive white blood cells. "We preferentially delete 'naive T cells', since they are the main subset of white blood cells that reject grafts," Strober says.

Another donation

About 10 days after the transplant, Strober injects the patient with millions of white blood cells extracted from the kidney donor. These include CD34+ stem cells, which can multiply and become part of the recipient's own immune system.

Once donor blood cells mix with recipient immune cells, they blunt the immune attack by a process called negative selection, says Strober, who has spent 30 years developing the regimen.

In negative selection, the thymus presents proteins from foreign tissue to immune cells, in effect asking them, "Do you recognise this material?" If enough immune cells recognise the tissue, those that don't are screened out and killed. Because donated immune cells recognise the foreign tissue from the transplanted kidney, the thymus gets rid of the recipient's own T-cells that could otherwise attack the kidney.

Strober monitors the recipient's blood regularly to check that the two immune systems are mixing properly, and there is no sign of rejection.

After a month, the first of two immunosuppressive drugs is withdrawn. The second is withdrawn at six months.

Three years free

Eight of Strober's 12 trial patients have now been free of immunosuppressive treatment for up to three years, although one died after three years from a heart attack unrelated to the treatment.

The other four are still on immunosuppressive drugs, but are being monitored to see if they too can break free. "So far, they've failed to meet our strict drug withdrawal criteria," says Strober.

Close match

One caveat is that all patients received donations from closely matched relatives. But Strober is confident that the regimen will work with unmatched donations too, which would greatly expand the number of organs available for the procedure. "Our preclinical lab results show that we can use mismatched recipients as well as matched, and that gives us confidence to move ahead," he says.

Although 17,000 people receive kidneys in the US each year, more than 400,000 are on the waiting list and rely on dialysis machines, so the shortage of available organs remains acute.

Strober's procedure is not the only one to free patients from anti-rejection drugs. In 2008 a team led by David Sachs at the Massachusetts General Hospital in Boston reported a technique involving a bone marrow transplant from organ donors, which worked in four of five patients – some of them have now been free of drugs for eight years.

Sachs says that Strober's work is encouraging, but points out that his own patients all received unmatched transplants, overcoming a greater immunological challenge. "The success rate they've reported is similar to what our studies have achieved for mismatched transplants," he says. "So it will be interesting to see the results of Strober's new trial."

One advantage of Strober's approach is that it is milder and less traumatic for the recipient than having a bone marrow transplant in addition to a kidney transplant, says Maggie Dallman, an immunologist at Imperial College London. But, like Sachs, she says that "the real test will come when this is used for mismatched organs".

Nanoscoop

Holland has the world's most advanced microscopes called

                                        Nanoscoop x 0,000000000

NeCEN, a new high quality centre for electron microscopy, opens its doors in Leiden on October 27th. NeCEN has two of the most advanced cryo-transmission electron microscopes worldwide. The microscopes are open to all research institutes and companies. Ten academic partners, local and national governments and companies collaborated to establish the centre. They expect that NeCEN will lead to giant steps forward in science and R&D.

From professor to politician

NeCEN is the result of a unique collaboration between science, industry and politics. That is why all three aspects will be addressed at the opening on October 27th. Holger Stark, from the University of Göttingen will explain more about electron microscopy during a guest lecture. After this, participants will explore the relation of NeCEN to science, industry and governments. Chairs of these workshops are Bram Koster (LUMC), Peter Peters (NKI-AVL), Dominique Hubert (FEI company) and Jeanette Ridder-Numan (Ministry OCW). Liesbeth Spies, deputy of economic affairs and innovation of Province Zuid-Holland will officially open NeCEN around 16:30.

Open access

Although NeCEN is housed by the Cell Observatory in Leiden, all scientists at companies and research institutes can get access. Ten companies have already written a letter of intent to support the centre during the startup phase, including HAL Allergy, Genencor and Danone. Besides these letters of intent, 15 more companies have recognized the added value of NeCEN. It is truly unique that two microscopes of this type are located together and can be used by every academic or commercial scientist.

Zooming in on life

The two NeCEN microscopes allow scientists to zoom in on cells, molecules and atoms. Incredibly small details can be seen; single atoms have already been distinguished in a virus with the same technology. The NeCEN microscopes are expected to show even more detail. Visualizing these details is the first step towards understanding how diseases work and hence its potential cures. Examples are tuberculosis, malaria and cancer.

For the press

We have prepared a special program for journalists between 15:30 and 16:30. This program will give you insight into the establishment of NeCEN and its relevance for science and industry. Speakers from research institutes and companies that plan to use the microscopes will be present and provide information about the applications. Among the companies are to-BBB and Prosensa. To-BBB develops methods for drug delivery across the blood-brain barrier. Prosensa develops therapies against the neuromuscular disease Duchenne. We also welcome you for the official opening between 16:30 and 17:30 and a visit to the microscopes at 17:45. You can register by sending an e-mail to necen@science.leidenuniv.nl.

Date, location and time

Date: 27 October 2011 Location: Gorlaeus Laboratory, Einsteinweg 55, Leiden
Time symposium: 12:30-16:30
Time programme for journalists: 15:30-16:30
Time official opening: 16:30-17:30

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Neutrino faster then speed of light

Faster-than-light neutrino claim bolstered

Representatives from the OPERA collaboration spoke in a seminar at CERN today, supporting their astonishing claim that neutrinos can travel faster than the speed of light.

The result is conceptually simple: neutrinos travelling from a particle accelerator at CERN in Switzerland arrived 60 nanoseconds too early at a detector in the Gran Sasso cavern in Italy. And it relies on three conceptually simple measurements, explained Dario Autiero of the Institute of Nuclear Physics in Lyon: the distance between the labs, the time the neutrinos left Switzerland, and the time they arrived in Italy.

But actually measuring those times and distances to the accuracy needed to detect differences of billionths of a second (1 nanosecond = 1 billionth of a second) is no easy task.

Details, details

"These are experiments where the devil is in the details – the details of how each piece of equipment works, and how it all goes together," said Rob Plunkett of Fermilab in Batavia, Illinois.

The detector in the Gran Sasso cavern is located 1400 metres underground. At that depth Earth's crust shields OPERA (which stands for Oscillation Project with Emulsion-tRacking Apparatus) from noise-inducing cosmic rays, but also obscures its exact latitude and longitude. To pinpoint its position precisely, the researchers stopped traffic in one lane of a 10-kilometre long highway tunnel for a week to place GPS receivers on either side.

The GPS measurements, which were so accurate they could detect the crawling drift of the planet's tectonic plates, gave precise benchmarks for each side of the tunnel, allowing the researchers to triangulate the underground detector's position in the planet. Combining that with the known position of the neutrino source at CERN gave a distance of 730,534.61 metres, plus or minus 20 centimetres.

To determine exactly when the neutrinos left CERN and arrived at Gran Sasso, the team hooked both detectors to caesium clocks, which can measure time to an accuracy of one second in about 30 million years. That linked the labs' timekeepers to within one nanosecond.

"These kinds of techniques that we have been using are maybe unusual in high energy physics, but they are quite standard in metrology," Autiero said. Just to be sure, the collaboration had two independent metrology teams from Switzerland and Germany check their work. It all checked out.

The researchers also accounted for an odd feature of general relativity in which clocks at different heights keep different times.

A ‘beautiful experiment'

Other physicists are impressed."This is certainly very precise timing, more than you need to record for normal accelerator operations," Plunkett told New Scientist. His project, the MINOS experiment at Fermilab, has already requested an upgrade to their timing system so they can replicate the results, perhaps as soon as 2014.

"I want to congratulate you on this extremely beautiful experiment," said Nobel laureate Samuel Ting of the Massachusetts Institute of Technology in Cambridge during the question and answer session that followed Autiero's talk. "The experiment is very carefully done, and the systematic error carefully checked."

But only time will tell whether the result holds up to additional scrutiny, and whether it can be reproduced . There is still room for uncertainty in the neutrinos' departure time, Plunkett says, because there is no neutrino detector on CERN's end of the line. The only way to know when the neutrinos left is to extrapolate from data on the blob of protons used to produce them.

"Of course we need to approach it sceptically," he says. "I believe everyone will be pulling together to figure this out."

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Sound waves can identify cancers that have spread

A device that filters cancer cells from human blood using sound could help to identify tumour cells that have spread.

Finding tumour cells in the blood indicates a cancer has metastasised – but the molecular markers that are used to identify the cells can modify them and make them unsuitable for studying how treatment is proceeding and for performing basic cancer research.

So Itziar González at the Institute for Acoustics in Madrid, Spain, and colleagues developed an alternative: a tiny vibrating plastic chamber through which a blood sample flows. The vibrations create a standing wave that deflects cells in the blood to a different degree depending on their size. Tumour cells are often larger than blood cells and so collect in a different region of the device. The process does not alter the cells.

The prototype can reliably differentiate cancer cells 70 per cent of the time, and a modified version that exposes the blood to the acoustic waves for a longer amount of time should be able to differentiate a cancer cell from a normal cell 95 per cent of the time.

That's important, because identifying just two or three tumour cells in a typical 7-millilitre sample of blood is enough to determine that a cancer is metastasising, González says. Miss that small number of cells because of problems with the sensitivity of a device and "we won't be able to make that diagnosis", says González.

David Beebe at the University of Wisconsin, Madison, thinks the technique has potential. "Not labelling the cells is an advantage" for cultivating and studying them, he says.

González presented the work at the International Conference on Microtechnologies in Medicine and Biology in Lucerne, Switzerland, last month.

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Dr.Zakir Naik Reply Florida Church Burn Quran Day on 9/11 part 2

KHOST NEWS

امریکا ( فلورید ا) کی قران شریف وسوزل شو Florida Church Burnt Holy Quran [by Pastor Terry Jones]

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Obesity expert: A better fat measure than BMI

You have come up with an alternative to the body mass index as a measure of obesity. First off, what's wrong with BMI?

The BMI has been around since the 1840s, but it has a number of weaknesses. Firstly, it doesn't give a real estimate of percentage body fat. Secondly, the BMI can be quite different for a man and a woman with the same percentage of body fat. And thirdly, your BMI can be high even if you don't have much fat, especially if you are male and very muscular.

How did you go about searching for an alternative to BMI?

Our goal was to find a simple index of obesity, something that a practising clinician could use. To do that we looked at a population of 2000 people of Latin American descent who had had their percentage body fat measured directly using dual-energy X-ray absorption, which is an accurate way to quantify body fat. We then asked what parameters we could measure in these people that would best predict the true percentage of fat.

What did you find?

It turned out that hip circumference and height were more correlated with percentage body fat than anything else, including waist circumference and weight. So we designed an equation that could take both of these into account. We call this the Body Adiposity Index. It turns out that BAI is a good predictor of percentage adiposity, so if your BAI is 30, then your percentage body fat is around 30 per cent. It is reasonably accurate - not terribly accurate - but usable as a clinical tool.

Is BAI better than BMI?

We think it's better, but we have still got to prove it. Unlike BMI, the BAI for men and women is the same if they have the same percentage body fat. We have validated the BAI in African American populations too. Its utility has not been confirmed in Caucasian subjects, although we have tested it on a small group and it seemed to fit.

What are the downsides of the BAI?

The real challenge is to be able to predict the risk of obesity-related diseases such as cancer, diabetes, cardiovascular disease and hypertension, and then to intervene. It remains to be shown that BAI is a more useful predictor of these outcomes than other measures of body adiposity.

Were you surprised that weight isn't part of the BAI calculation?

Yes. But this means that BAI has the unexpected characteristic that it can be used where scales are unavailable or not correctly calibrated. BAI could be useful in remote locations with no reliable scales; in India, for example, where obesity is a serious problem.

Do you think BAI will one day succeed BMI as a measure of obesity?

I am agnostic on that, but I'm hopeful that BAI is better than BMI, which is misused by a lot of medical practitioners who don't realise that it is often not a good measure of percentage body fat.

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Sperm cells grown from scratch

FOR the first time viable mouse sperm have been grown outside the testes. If the technique can be repeated with human sperm, it could lead to new ways of treating infertile men.

Takuya Sato at Yokohama City University in Japan and colleagues extracted germ cells from the testes of newborn mice that had not yet begun producing sperm. They placed the cells in agarose gel soaked in nourishing chemicals and hormones such as fetal bovine serum and testosterone. The team had first engineered the mice so that a protein only present in fully grown sperm would fluoresce green. Sure enough, around one month later, the team spotted the glowing protein in nearly half of their samples.

Sato's team then fused the sperm with eggs from female mice and created healthy embryos. When these embryos were implanted into females they produced healthy offspring which were able to mate and give birth to their own pups.

The team also confirmed that the testes tissue could be frozen and thawed without damage (Nature, DOI: 10.1038/nature09850).

"People have been trying to do this for years, but it takes an awful lot of trial and error," says Erwin Goldberg, a cell biologist at Northwestern University in Chicago, who was not involved in the study. The key to the team's success, Goldberg says, was patience: they kept mixing chemicals in the lab until they found exactly the right recipe to keep testes cells alive in a petri dish and satisfy all their nutritional requirements.

Earlier studies using different methods achieved similar, but less promising results. In 2006, Karim Nayernia at the University of Newcastle, UK, transformed stem cells from mouse embryos into sperm cells but most of the offspring died prematurely.

If researchers could convert germ cells from an infertile man into sperm cells, they might be able to pinpoint exactly where something goes wrong in the sperm's development and fix it, says Martin Dym, a reproductive biologist at Georgetown University in Washington DC.

The technique could also help prepubescent boys with cancer, who are not yet producing mature sperm, by growing sperm cells that can be frozen before radiation therapy.

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نوروز سال ۱۳۹۰

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Nathan Myhrvold: From Microsoft to molecular gastronomy

Nathan Myhrvold: From Microsoft to molecular gastronomy

Nathan Myhrvold may hold a record for the widest variety of interesting careers before the age of 50. He worked as a physicist alongside Stephen Hawking, then became chief technology officer for Microsoft. He's now turned to the science of cooking, and tells Amanda Gefter about busting cooking myths while simultaneously combating global warming and malaria

You are best known from the world of technology, but you're also a master chef. When did you first get interested in cooking?

When I was 9 years old I told my mother I was going to cook Thanksgiving dinner. I can't say that I did a great job of it, but from that point on I was really interested in cooking. In the mid 1990s, I took a leave of absence from Microsoft, where I was a senior vice-president and chief technology officer, to go to chef school in France. The chef school wouldn't accept me until I had professional work experience, so for two years I worked one night a week at a restaurant in Seattle.

You've just published a cookbook, Modernist Cuisine. At over 2400 pages, it sets out to reinvent cooking. What inspired it?

Originally I thought it would be a huge book, but my idea of huge was 600 pages. We just kept finding more cool things to do. The inspiration was that there was no definitive source from which you could learn all about modern cuisine, covering the science of cooking and the techniques that have come to be in the last 10 to 20 years. So we thought there's an opportunity to be that big definitive book and, in the process, it went from what we thought was a huge 600 pages to 2400.

Do you have to be a chef or a scientist to use Modernist Cuisine?

We went to a lot of effort in the book to tell the scientific story of cooking in an accessible way so people who are not chefs or scientists will still find it fascinating. If you're curious about how the world works, knowing the science behind it makes it all the cooler. If you stand at the edge of the Grand Canyon, understanding the processes of geology that caused it gives you a better appreciation of it. There are some people who say "stop with the geology; don't ruin the view for me". I'm not one of those people.

We also went to a lot of effort taking photographs to illustrate the book, because cool pictures are a way to seduce people into getting interested in a technical topic.

In studying the science of cooking, have you found that there are certain folk-wisdom cooking techniques that turn out to be wrong?

A lot of them are quite wrong. For example, it is a common cooking technique to plunge something into ice water to stop the cooking. But it turns out it doesn't stop the cooking any quicker than if you leave it out on the counter. That's very counter-intuitive.

Here's another example. Suppose you're cooking a steak that's 1 inch thick and now I tell you to cook a steak that's 2 inches thick. Most people would agree that cooking the 2-inch steak will take longer, but how much longer? Intuition tells you it should be double the time. But heat conduction in things with similar geometry scales roughly as the square of the thickness. So it will take roughly four times as long. That's a simple rule, but I've never found a cookbook that says that.

Do people need high-tech equipment to make most of the recipes in the book?

To make some of the recipes, yes, but not for most. For a bunch of the recipes you need a blender. If you have something called a rotor-stator homogeniser it will work better than a blender, but a blender will work. For some of the recipes you need sous-vide cooking equipment, which involves cooking in a water bath. We decided not to dumb down the book, either in a conceptual way or in terms of the equipment.

You also use ingredients like enzymes and hydrocolloids that food purists might baulk at. What is your response to them?

People say: "Isn't your food full of chemicals?" And I say: "Yes, and full of elements too! Your food isn't?" Because, of course, all food is chemicals and all cooking is chemistry. The fact is, so-called traditional cuisine is all full of similar and in some cases the same things.

Where do you think the baking soda in your organic muffins came from? Or how about sucrose? Sucrose, until about 100 years ago, was an exotic thing that was bought from apothecary stores. It wasn't until a new industrial process allowed it to be created in bulk that sucrose, ordinary table sugar, got to be cheap enough for everybody to use it. Almost every ingredient has a story like this and it's inconsistent to say, "Oh, I like a traditional food like X, but not this new stuff," when the traditional foods are full of things which are just as much a chemical.

You began your career as a theoretical physicist, working with Stephen Hawking. Why did you give that up?

I never decided to go out of it. I got involved in a software project with a couple of friends and I took a leave of absence for three months to finish that up. At the end of the three months we started a company so I kept extending my leave of absence. Then after running my company for two years, Microsoft bought it. After being at Microsoft for 14 years I announced I was taking a leave of absence; the next day I get this email from Stephen Hawking saying, does this mean you're coming back?

In 1983, the allure of the nascent world of software, computers and what became the internet was tremendously exciting. I still love physics, I still try to keep up with it.

At the company you co-founded after leaving Microsoft, Intellectual Ventures, you're working on a solution to climate change...

Yes. As well as inventing for profit, we do inventions for humanity. One of the crazier ones we do is geoengineering. Right now it's hard to have a good feeling that we're going to solve the problem of climate change. Maybe the world will get its act together in time. But what if it doesn't? I think it is prudent to have a back-up plan. One way to stop global warming is to make the sun 1 per cent dimmer. We can't stop the sun, but if we put a little bit of material high in the atmosphere, we can scatter a little bit of sunlight back into space.

How would you do this?

With sulphur dioxide. It's good at scattering light, it's natural, it's in volcanoes and there's lots of it there already. Our contribution was to think, how the hell are you going to get it up there in a way that's reasonably cheap? We came up with the idea of taking a long hose and putting a string of balloons on it and pointing it up to the sky. All the calculations suggest that it works. That is about as far as we're going to go with it. Our basic thrust is to get this out there, and hopefully people will take these ideas seriously and test them to see whether they work or not.

You are also working on malaria. Why did you take on this problem?

We started a programme of inventing things to solve problems in the developing world. Malaria is a terrible disease and we've not made a lot of progress tackling it in the last 40 years. If the world can solve it the conventional way, good. But we're going to think outside the box and see if we can come up with some wacky, crazy ideas that might fail but if they work could change everything. We have half a dozen projects for malaria - making malaria diagnostics and doing studies on mosquitoes to understand how they fly and how to deter them. One of those is this idea of shooting mosquitos out of the sky with lasers. These lasers could be used as a perimeter defence around schools, clinics or fields.

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Japanese nuclear crisis spreads to two more plants

1920 GMT, 13 March 2011

Three days after a magnitude 9.0 earthquake and ensuing tsunami struck Japan, killing an estimated 10,000 people and leaving many more destitute, the country is still struggling to avert nuclear disaster, with problems reported at four separate nuclear power plants.


The Tokyo Electric Power Company (Tepco) is continuing attempts to cool down two reactors at the Fukushima-Daiichi plant 240km north-east of Tokyo, where a dramatic explosion destroyed the roof of the building housing reactor No. 1 on Saturday. Seawater mixed with boric acid has been introduced to reactors Nos. 1 and 3 in an attempt to cool the reactors' cores and kill the nuclear fission reaction more quickly.


It's not clear how much progress has been made, although nuclear power experts canvassed by Reuters were cautiously optimistic that the situation was being brought under control.  The Japanese government has acknowledged that fuel roads at one or both reactors may not have been fully submerged for a time, and may have melted or become deformed as a result, but that would fall short of a complete meltdown and does not necessarily constitute a risk to the public unless the situation worsens.






Japan's nuclear safety agency also faces an emergency at Tokai nuclear power station, 120km from Tokyo in Ibaraki Prefecture, where one of two cooling systems has stopped. But the Japan Atomic Power Company, which operates the plant, says that the remaining systems are working effectively and the reactor core is cooling smoothly.


At a third nuclear plant, in Onagawa, Miyagi Prefecture, an initial report of elevated radiation levels led to a low-level emergency being declared, but Tohoku Electric, the company that runs the Onagawa plant, said the cooling systems at all three reactors are functioning properly. The BBC reported that the increase in radiation was brief, with one possibility being that it originated at the Fukushima plant.


The site causing greatest concern is reactor No. 3 at Fukushima-Daiichi, whose plutonium-uranium fuel mix poses a greater radiological risk than that of reactor no. 1. Chief Cabinet Secretary Yukio Edano said at 20.00 local time on Sunday that water levels within the pressure vessel could no longer be confirmed to be increasing and that there was a "high possibility" that a valve used to vent steam was malfunctioning. Earlier in the day, Tepco had warned that an explosion like that at reactor No. 1 was possible.


A state of emergency has also been declared at the nearby Fukushima-Daini plant, where preparations to vent steam to reduce pressure have been drawn up but have not yet been implemented. More than 200,000 people have been evacuated from the vicinity of the two nuclear plants, although the Japanese government continues to stress that the radiation known to have leaked thus far poses little risk to human health.


The difficulties at the nuclear power plants, as well as other power generation facilities, mean that rotating power outages will be imposed across Japan as of Monday.

1300 GMT, 13 March 2011

Rowan Hooper, news editor
As fears grow of an explosion at the number 3 reactor in the Fukushima-Daiichi nuclear power plant, Japanese prime minister Naoto Kan said in a press conference that the disaster was the worst since the atomic bombing of Hiroshima and Nagasaki in the second world war.
Unlike the uranium-based Fukushima number 1, the number 3 reactor uses a mixture of plutonium oxide and uranium oxide. In the event of a meltdown, plutonium is considered more dangerous than uranium alone because of its increased volatility and its reactive, "neutronic" effects.
Michael Bluck, a nuclear engineer at Imperial College London, told New Scientist that plutonium is used because it increases the efficiency of power generation. "It improves the burn up, so you get more energy out of the fuel than if you just use uranium dioxide (UO₂). Plutonium dioxide enhances burn up in normal situations in a controlled reactor, so it may result in even greater heat generation in the event of a meltdown than is the case with UO₂ alone. It's why plutonium is used in nuclear weapons, because it is more reactive and produces more energy."
Bluck notes that plutonium is produced anyway in a "UO₂ only" reactor, as part of the fission process. Adding plutonium at the beginning just gives us more.
The danger is that in the event of a meltdown there would be even greater generation of heat, with the additional demands of cooling. Metallic plutonium is a serious fire hazard, Bluck added, further complicating the situation.
To prevent the catastrophe of a meltdown, boric acid - a water solution containing boron - is being pumped into the number 3 reactor. Boron is used because it captures neutrons and reduces the risk of a fission chain reaction. It is being pumped with sea water into the reactor.
Japan generates about a third of its electricity from nuclear power. In order to conserve energy during this crisis, Kan warned that there will be rotating power outages across Japan.
"There have been quite a few nuclear power plants affected by this earthquake," he said. "We have no prospect of restoring electricity supply within the next few days therefore there is a good possibility that we will remain without electricity - and there may be a possibility of large scale blackouts. These will affect people's lives and industrial activities. And we have to avoid large scale unexpected blackouts, so from tomorrow in the area covered by Tepco I have asked them to apply rotating outages."
Meanwhile the Japan Meterological Agency warned that there is a 70 per cent chance of a magnitude-7 aftershock striking the country in the next three days. It said there is a 50 per cent risk over the three subsequent days.

0030 GMT, 13 March 2011

Sumit Paul-Choudhury, editor, newscientist.com
Cooling systems have failed at a second reactor at the stricken Fukushima Daiichi nuclear power plant, where a massive blast ripped through a reactor building on Saturday. The Tokyo Electric Power Company, which operates the plant, said it was preparing to release mildly radioactive steam to reduce pressure in the plant's No. 3 reactor.
The move follows the decision to use seawater mixed with boric acid to cool the No.1 reactor, whose core container remained intact despite a dramatic explosion which destroyed the walls and ceiling of the reactor building. The expectation is that the boron will kill the nuclear reaction while the corrosive seawater will cool the core and render the reactor unusable. Tepco described the reactor as "stable" late on Saturday and the Japanese government said radiation levels around the plant had decreased.
Around 200,000 people have now been evacuated from the vicinity of the Fukushima Daiichi plant and the nearby Fukushima Daini plant, where a state of emergency has also been declared and plans to vent steam have also been prepared. Up to 160 people may have been exposed to radiation, and those arriving at evacuation centres are being scanned and given iodine supplements. Iodine is used to mitigate radiation sickness.

1740 GMT, 12 March 2011

Roger Highfield, magazine editor, and Yuriko Nagano, contributor, Tokyo
A turning point in the efforts to avert a meltdown at Fukushima Daiichi nuclear power station came in the wake of the blast that destroyed the exterior walls of the crippled reactor.


The emergency began when the magnitude 8.9 earthquake which rocked the region on 11 March put the 439 MWe Boiling Water Reactor into shutdown mode.
Even after shut down, however, a reactor still requires cooling. Diesel generators initially supplied cooling water but they failed about an hour after the quake as a result of the tsunami, prompting fears of a meltdown. The pressure in Fukushima 1 started to rise, as the cooling water covering the core boiled into steam. Malcolm Grimston, an associate fellow at Chatham House in London, said that the fuel began to overheat.
At around 1500 ºC, the zirconium metal cladding the uranium fuel would react with the steam to form hydrogen.
If any of the fuel rods have been compromised, there would be evidence of a small amount of other radioisotopes called fission fragments (specifically radio-caesium and radio-iodine), according to Paddy Regan of Surrey University.
Regan added that while the intergrity of the pressure vessel is secure, the vast majority of the fission fragments and radioactive fuel material is safely contained within the pressure vessel and should not escape.
However, the pressure in the steel vessel would have increased inexorably.


The Tokyo Electric Power Company, Tepco, had the flexibility to use pressure release valves to vent some steam, even though it was mildly contaminated, because it had taken the precaution of evacuating the local population within a 12-mile radius. Grimston described this as "extraordinary forward planning".
The steam was released from the pressure vessel into the surrounding building and this was consistent with reports that radiation levels had soared to around 1000 times the background level. Officials also said they had detected caesium, an indication that some fuel was already damaged.
The blast occurred at 3:36 PM local time after a large aftershock shook the plant, though Grimston said that it was not clear the two were connected.
The shock wave that can be clearly seen in video of the blast suggests a point ignition source detonated the released hydrogen when it came into contact with oxygen in the air, he said.
Four workers were injured, according to Atsushi Sugimoto of Tepco.
"At this point, we don't know how much radiation has escaped," said Shinji Kinjo of the Nuclear and Industrial Safety Agency. "Should the situation change, the evacuation zone could become larger."
Yukio Edano, Japan's chief cabinet secretary, said the cause of the explosion was a mixture of hydrogen, from steam escaping the core, and oxygen from the surrounding air.
He added that the pressure vessel was unaffected and the incident would not be a cause for a large amount of radiation to leak.
Although the concrete cladding disintegrated in a spectacular fashion, Grimston said that the fact that the metal frame of the building was left intact suggests that the explosion was not as violent as it looked.
Because the plant went into operation in 1971 and is due for decommissioning, the decision was taken by Tepco to flood it with seawater containing boric acid to kill the nuclear reaction.
This began just after 2 pm UK time and would take up to 10 hours.
The use of corrosive seawater would render the reactor unusable but would ensure that the risk of a meltdown had been averted, said Grimston.
He said that, if the information he had received was accurate, it looked a "textbook example" of how to deal with a nuclear emergency.
Tepco said Fukushima was stable but remained sketchy on key details.
More measures are under way to protect the local population. "The authorities also say they are making preparations to distribute iodine to residents," said the International Atomic Energy Agency.
Meanwhile, an official at Japan's nuclear safety agency rated the incident a 4, according to the International Nuclear and Radiological Event Scale. Three Mile Island was rated a 5, while Chernobyl was rated 7 on the 1 to 7 scale.
The Kyodo news agency reported that some 10,000 people in the town on Minamisanrikucho, in Miyagi prefecture, are missing in the wake of yesterday's tsunami.

1230 GMT, 12 March 2011

Jeremy Webb, editor-in-chief and Rowan Hooper, news editor
Details are emerging of the explosion at the nuclear power plant in Fukushima on the east coast of Japan, 240 kilometres north of Tokyo.
The blast blew off the outer concrete shell of a building housing one of the six reactors at the Fukushima Daiichi (number 1) nuclear power station, leaving behind a skeleton of metalwork. Four workers are reported to have been injured at the site and radiation is leaking into the environment. Japanese authorities have extended the evacuation zone around the plant to 20 kilometres.


Chief Cabinet Secretary Yukio Edano told a press briefing that the pressure vessel that houses the radioactive core of the plant is intact, and that a large amount of radiation leakage is not expected. He said that radiation is remaining at a low level. The Japanese news agency Kyodo earlier reported levels of 1050 micro Sieverts - within Japanese national safety levels - around the explosion at the Fukushima 1 reactor building.
Edano announced that the Tokyo Electric Power Company (TEPCO), which runs the Fukushima facility, will be allowed to use sea water to cool the reactor down.
The cause of the explosion is still unclear, but suggestions include a build up steam released from the reactor cooling system or by the ignition of hydrogen gas. That hydrogen could have been liberated by water "cracking" in the ultra high temperatures in the reactor.
Trouble at Daiichi began on March 11, when the earthquake struck offshore, northeast of Fukushima. The plant tripped out immediately, as it's designed to do, shutting down the chain reaction in the core.
The reactors at the Daiichi station are boiling water reactors built by US company GE in the 1960s. Water passes up through the core, turning into steam, which powers the turbines to generate electricity. The steam is then cooled and pumped back into the core.
When the reactor trips out, water needs to keep circulating to remove residual heat in the core. But, according to TEPCO, an hour after the earthquake, the diesel engines running the cooling system failed. This led to evaporation of water in the core and a build up of steam in the pressure vessel.
TEPCO managed this by releasing the steam from the pressure vessel into the large surrounding building. This appears to be the building that has exploded.
If heat continues to build up in the core, there is a possibility that it could melt, as happened in the Three Mile Island accident in the US in 1979.

1130 GMT, 12 March 2011

Paul Marks, senior technology reporter
A massive explosion has ripped through a nuclear power plant in the city of Fukushima on the east coast of Japan, raising fears of a radioactive meltdown. Four workers are believed to have been injured in the blast, which has caused major structural damage. Radioactive caesium and iodine isotopes, by-products of nuclear fission, have been detected in the vicinity.
A state of nuclear emergency was declared yesterday at the Fukushima-Daiichi plant, 240 kilometres north of Tokyo, as its operator, the Tokyo Electric Power Company (Tepco), struggled to contain rising temperatures and pressures in the core of two reactors whose cooling systems failed after Friday's magnitude 9.0 earthquake shook Japan and sent tsunami waves across the Pacific. Tepco has also reported problems at the nearby at the neighbouring Fukushima Daini plant, meaning that a total of five nuclear reactors are now covered by the state of emergency.
It is not yet clear what has been destroyed, but Japan's public broadcaster NHK is reporting that the walls to reactor number 1 at the Fukushima Daiichi plant - also known as Fukushima I - have been blown apart. It is not yet known if the reactor's containment vessel was affected. Nor is the cause of the explosion yet known, although commentators for the BBC and for Reuters suggested it was more likely to be chemical in nature than nuclear.
Updates from the Tokyo Electric Power Company over the few hours preceding the explosion indicated an inexorable build up of pressure in a number of the reactor containment buildings at both Fukushima sites.
All six of Fukushima 1's reactors are shut down - reactors 1, 2 and 3 were closed for precautionary reasons as the quake struck, while reactors 4, 5 and 6 had already been switched off for inspections. At 1pm local time on 12 March, TEPCO reported that pressure was increasing in the containment vessel of reactor 1 and that it was taking steps to vent the pressure at the direction of the national government. At the same time, water was being introduced in a bid to cool the core - but that creates steam and adds to the pressure.
It appears from the explosion that the TEPCO lost its battle to keep the lid on the pressure on that reactor. If the temperature is still rising the core could melt into an uncontrollable radioactive-particle-ejecting mass - a "meltdown".
At the nearby Fukushima II plant an alarm suggested that one of the control rods used to quench the fission reaction had not been fully inserted - perhaps meaning that fission could continue. The alarm was later called off and Tepco said that other control rods had been confirmed as fully inserted, but the pressure and temperature nonetheless increased enough for another radioactive steam venting operation to be prepared.


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Play Station 3 Afghanistan Game

Call of Duty: Modern Warfare 2 Video Game, Afghan Gameplay Part II (Cam) Video Clip Game Trailers & Videos GameTrailers.com

KHOST NEWS

Khost University Students

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4G network 'will create GPS dead zones across the US'

WHAT would you rather have - a superfast data connection on your cellphone, or a reliable GPS signal to pinpoint your location? If a plan to install a network of base stations for the new 4G mobile wireless protocol goes ahead, it may mean you can have one but not the other.

GPS satellites transmit their navigation signals in the range 1559 to 1610 megahertz. Telecoms firm LightSquared of Reston, Virginia, has long communicated with its satellites using low-power signals in the adjacent frequency band, from 1525 to 1559 MHz, part of the "L band". Despite the closeness of the frequencies, satnav receivers have so far operated without any interference problems.

But in January, the US Federal Communications Commission (FCC) gave preliminary approval to a plan by LightSquared to build 40,000 new 4G base stations on the ground. These stations would broadcast much stronger signals in the 1525 to 1559 MHz range, to link to cellphones.

Based on lab simulations of the new transmissions, Scott Burgett and Bronson Hokuf, engineers with satnav manufacturer Garmin International in Olathe, Kansas, say this will seriously damage GPS reception. In a report to the FCC last month, they say that overlaps between the two systems are inevitable, and that this "will result in widespread, severe GPS jamming [and] will deny GPS service over vast areas of the United States".

Jeff Carlisle of LightSquared says it is the GPS receivers, not his company's base stations, that are at fault. "The issue is that some GPS receivers may be able to see into the L band where we operate," he told New Scientist.

The stakes are high. By 2015, LightSquared expects to spend $6 to $8 billion to complete the network, which promises to bring download speeds of 5 to 10 megabits per second to cellphone users. Meanwhile, over a billion GPS receivers are in use worldwide.

LightSquared has until 25 February to submit a plan to the FCC for working with the GPS industry and federal agencies to analyse interference issues; a final report detailing a solution is due by 15 June. LightSquared wants all future tests to be performed with real transmitters rather than simulators.

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The Pill to Increase Brain Capability

For so many years the pill has been used by millions of women to prevent pregnancy. It is known that the pill reduces the risk of certain diseases. However, in a recent study it was found that using birth control pills could actually have a beneficial effect on the brain as well. It was discovered that those that used it resulted in a three percent increase of brain size.

Dr. Jennifer Wu, an obstetrician at Lenox Hill Hospital (New York) states that MRIs of women using the pill display certain regions of the brain to be larger than in women who do not use the pill. The areas in the brain were found to be larger had to do with speech, memory, and communication.
Having a larger brain does not necessarily mean it is better. It is suggested though that the areas of the brain that grow in a women due to the pill will result in greater brain power. For example, a woman may find that her memory is improving.
There are many theories that explain how the pill could improve the capability of the brain, however, it is not known for sure and has not been proven. As a result of this study much more research is being done in regards to how hormones can affect the brain and how the pill could possibly increase brain size.
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Low sperm count? Your bones might be to blame

Sex hormones are already known to play an important role in maintaining healthy bones – but the relationship may be a two-way street. New evidence suggests that bones are important for controlling testosterone levels.

Gerard Karsenty at Columbia University in New York City and his colleagues applied osteoblasts – bone cells involved in building new bone – to cultures of cells taken from either the testes or ovaries of mice. They found that testis cells treated with bone cells increased their production of the hormone testosterone threefold. The cells from the ovaries, on the other hand, showed no change in their production of the hormones progesterone and oestradiol.

Karsenty's team then focused in closer by looking at osteocalcin – a hormone produced by osteoblasts. They found that testis cells treated with an active form of the hormone released testosterone – and the more of the hormone they got, the more testosterone they produced. Injecting live mice with the hormone similarly boosted levels of testosterone in their bloodstream.

To find out if this effect on testosterone production might affect mice's fertility, the team knocked out the gene for osteocalcin in a group of the rodents. These modified mice had significantly smaller testes and lower sperm counts than their normal counterparts – and when the group bred them with normal females, they found that the litter size was around half normal.

Mice and men

Rebecca Sokol at the University of Southern California in Los Angeles is intrigued by the findings. "I am particularly surprised by the absence of effects in female mice," she says.

Karsenty is stumped too. "We were flabbergasted," he says. "Don't ask me why it only affects males because I don't know."

He thinks the hormone might also boost fertility in men, as many hormones have been found to have the same effects in mice and humans. His team are currently exploring the possibility of osteocalcin as a treatment option for infertile men.

Bone is already known to release hormones. A few years ago, the same group found that osteocalcin plays a role in maintaining the body's glucose levels (Cell DOI: 10.1016/j.cell.2007.05.047).

Botox.(botulinum toxin – a protein )

Beyond erasing wrinkles, Botox can now help people who spend more than half their lives in headache agony. But is there enough evidence to support treating chronic migraine sufferers with regular shots of the toxin around the head and neck? Doctors are divided

What is Botox?

Botox is the trade name for botulinum
 toxin – a protein produced by the Clostridium botulinum bacterium. By blocking the release of a chemical messenger in the brain, the toxin stops muscles from contracting.

Why try preventing migraines with it?
The story starts around 10 years ago, with some of Hollywood's most revered residents – cosmetic surgeons.

"The plastics people suggested that some of their patients had relief from migraine after Botox treatment," says Peter Goadsby, director of the University of California, San Francisco's Headache Centre.

The idea began to spread and clinicians started giving Botox as an "off-label" treatment – that is, in a way not approved by regulators – to people with migraines.

Allergan, the pharmaceutical company that developed Botox, soon cottoned on and started marketing Botox as a migraine treatment. However, with no proof that the treatment worked, last year the company was fined $375 million for unlawful marketing.

Since then, a number of clinical trials have ruled out any significant reduction in normal tension headaches and non-chronic migraine after Botox treatment.

Chronic migraine differs from ordinary migraines and tension headaches, however. In chronic migraine, the
person has a headache on more than 15 days of each month, at least eight of which are migraines.

What is the evidence for using Botox for chronic migraine, then?

Two clinical trials have investigated this. In both, people with chronic migraine received a series of five 12-weekly rounds of injections of either Botox or a placebo. In each round, individuals were given 31 injections at specific sites around the head and neck.

The first trial concluded that the Botox injections had no effect on the number of headaches experienced by those with chronic migraine, but hinted that the number of days affected by migraine might have been reduced.

When the same team looked at the latter outcome in the second trial, they found a 10 per cent reduction in the number of headache days compared with the placebo group.

How is Botox thought to help chronic migraine?
No one knows. The general consensus is that the blocking of muscle contraction isn't involved in headache relief, says Goadsby. Beyond that, researchers are generally stumped.

How solid is the evidence that Botox works?
Solid enough for the US Food and Drug Administration and the UK Medicines and Healthcare products Regulatory Agency: both bodies approved the therapy for chronic migraine last year.

Others remain unconvinced. Jes Olesen, a neurologist at the University of Copenhagen and chief of the Danish Headache Centre at Glostrup University Hospital in Denmark, has identified a number of faults in the trials, listed in a letter to The Lancet in November. His concerns were echoed in an editorial published in Drug and Therapeutics Bu
lletin this month.

Why is there a dispute?
According to Olesen, over half the trial participants overused pain medication, so the researchers wouldn't have been able to tell whether the participants had chronic migraine or medication overuse headache. What's more, it's impossible to hide the fact that people are receiving Botox, he adds – and that would invalidate the double-blind nature of the experiment. "Their facial expressions change," he says.

Even if you were able to get over those issues, the 10 per cent improvement pales in comparison to the usual 20 to 30 per cent required for most approved drugs, he says. "The FDA has committed one of the biggest blunders in regulatory history."

Sheena Aurora, neurologist at the Swedish Pain and Headache Center in Seattle, Washington, and lead researcher in the clinical trials, says the criticisms are "shocking". People with chronic migraine regularly take painkillers, so the trial represents the real-life situation, she argues.

The placebo group saw a 30 per cent response to the injections, compared with a 40 per cent response from the real injection. This indicates that people weren't looking for changes in their appearance to judge pain relief, either, she adds. And as for the 10 per cent improvement of the Botox group over the placebo group: "Who are we to say 10 per cent isn't enough for these patients?"

Goadsby agrees. "People with chronic migraine are highly disabled and have an unmet need for therapy," he says. "Everyone in clinical practice knows that chronic migraine is very difficult to treat."

While academic criticisms of trials are interesting, Goadsby says, they're not helpful to the millions of migraineurs. "Worrying about a little stone on the road is interesting, but we need to look at the bigger picture."

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Protein dose reverses learning problems in Down's mice

LEARNING and memory problems have been reversed in mice with a syndrome that mimics Down's.

Catherine Spong and colleagues at the National Institutes of Health in Bethesda, Maryland, found they could prevent developmental problems in mice engineered to have Down's syndrome by injecting their mothers with two proteins, called NAP and SAL, while they were still in the womb. This treatment would carry many risks for humans, so the team wondered whether the proteins might also help adult mice.

Spong's team engineered mice to have an extra chromosome 16, which causes similar problems to those caused by an extra chromosome 21 in humans, the trigger for Down's (see picture). The mice then had to find a submerged platform in a water maze using visual cues. Down's mice usually take twice as long to find the platform as healthy mice. However, after four days of oral treatment with NAP and SAL, the Down's mice learned to navigate the maze just as easily as normal mice.

NAP and SAL are fragments of proteins normally produced by glial cells - brain cells that provide nourishment to neurons. We know that glial cells malfunction in people with Down's. Mice treated with the proteins had markers of healthy glial function that were missing in the untreated Down's mice.

In a second experiment, the team investigated whether the treatment caused changes in chemicals known to be involved in "long-term potentiation" (LTP) - a type of brain activity key to memory formation. People and mice with Down's have decreased levels of many chemicals involved in this process. However, treated mice appeared to have increased levels of a receptor called NR2B that is responsible for initiating LTP (Obstetrics & Gynecology, DOI: 10.1097/AOG.0b013e3182051ca5). Craig Heller, co-director of Stanford University's Down Syndrome Research Center in California, says this study makes one thing clear: "Learning disabilities and mental retardations that were considered permanent are treatable."

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Robots

Robots in 1921, there has been an expectation that robots would some day deliver us from the drudgery of hard work. The word - from the Czech "robota", for hard labour and servitude - described intelligent machines used as slaves in his play R.U.R. (Rossum's Universal Robots).

Today, over one million household robots, and a further 1.1 million industrial robots, are operating worldwide. Robots are used to perform tasks that require great levels of precision or are simply repetitive and boring. Many also do jobs that are hazardous to people, such as exploring shipwrecks, helping out after disasters, studying other planets and defusing bombs or mines.

Robots are increasingly marching into our lives. In the future, robots will act as carers, medics, bionic enhancements, companions, entertainers, security guards, traffic police and even soldiers.

Domestic invasion

Despite the longevity of the robot concept, robotic butlers that roam our homes and relieve us from housework still seemed far from reality until very recently. Instead, the vast majority of robots worked in factories performing the industrial functions of brainless machines.

However, a combination of increased computing power and advances made in the field of artificial intelligence, or AI, have now made software smart enough to make robots considerably more useful.

A recent report published by the United Nations revealed that sales of domestic robots had tripled in a single year. What's more, they were well on their way to outstripping their industrial cousins.

While a large portion of the household robots were made up of robotic vacuum cleaners, mops, lawn mowers, pool cleaners, security bots and even robotic baby-rockers - the real boom was in entertainment robots.

Suddenly people were happy to pay for robots that had no specific functional value. Instead these bots, such as Sony's Aibo robotic dog and its robo-pups served as robo-pets and companions, rather than slaves.

This is partly because many domestic chores still pose a real challenge for robots, in terms of dexterity and intelligence, even with seemingly simple chores such as ironing.

Movers and shakers

Away from the domestic front, the modern bot can take many other forms. Some are even designed to change their form, such as shape-shifting tetrabots or self-cloning robots.

And while we often think of robots being humanoid, such as Honda's Asimo and Sony's Qrio, there is as much interest, if not more, in emulating other creatures like insects, lobsters, orang-utans, alligators, snakes and fish. A robot guard dragon has even been created.

Whether they have two legs, many legs, or no legs at all, considerable advances have been made in robot locomotion, including bipedal walking, rambling, crawling, rock-climbing, bouncing, slithering and swimming.

There are also wheeled bots that work as autonomous vehicles, such as the desert racers that compete in the DARPA Grand Challenge to be the fastest to cross a desert without any human control.

Robot wars

One area where even more advances in autonomy have been made is the development of unmanned aerial vehicles, or UAVs. These are essentially remotely-controlled spy planes that are capable of flying themselves if they lose contact with their pilot. These planes can also be used to monitor forest fires. Some robots have even learnt to fly of their own accord.

The Pentagon has started arming some UAVs, making them capable of responding with firepower against aggressive attacks - so-called unmanned combat vehicles, or UCVs. Robots that act as battlefield spies have also been designed.

Also aiming to remove humans from dangerous situations are space agencies, such as NASA, who have developed many space exploration robots. For example, the robonaut is a remotely-operated robot, designed to perform dangerous space walks in the place of an astronaut.

In addition, NASA has already sent robotic rovers to Mars, developed robotic dirt scoopers, "flying eyes" and probes for interplanetary exploration and even sent droids off to try to explore asteroids. Space probes such as Huygens (which landed on Titan) and Russia's Venera 9 (which landed on Venus) are sometimes considered robots too.

And it's not just other planets that robots are good for exploring. Robotic submarines, also known as remotely operated vehicles, or ROVs, have now become important way of exploring the deep ocean or ice-capped waters, while heat resistant robots are now used to patrol and monitor the activity in volcanoes. A robotic rover has even been used to explore Egyptian pyramids.

Precision surgeons

Operating on the human body requires high skill but also great control, something robots can provide. The idea of robotic surgery prompted early fears of unsupervised robots let loose to operate, but the reality is that robots now assist surgeons to perform precision procedures.

The most successful of these is arguably the da Vinci robotic surgical system, which is used for keyhole surgery, to operate on anything from gall bladder removals and brain surgery to heart bypasses.

Similarly, tiny, wireless and robotic camera-capsules have been used diagnostically, by allowing them to pass through a patient's digestive system. Others have been designed to move about by remote control in the abdominal cavity, beaming images back to the surgeon, or even taking biopsy samples. Robot hands have even been developed to scan for breast cancer.

Such life-saving robots have proved so successful that dentists are considering using robotic dental drill to make implant dental surgery cheaper, quicker and, crucially, less painful.

Actuators and sensors

But despite all the successes, there are still many challenges in robotics. These include producing better actuators (which control how robots move), sensors (which allow them to detect their environment) and ultimately making bots much smarter.

Current motors, and hydraulic or pneumatic actuators, are either too weak, or too bulky and noisy. Artificial muscle might be one solution, but so far these have failed to be strong enough to beat even a teenage girl in a robotic arm wrestling match.

Bipedal and humanoid robots have proved a particular problem. Robots on wheels, or those that move like insects, have found it much easier to balance and get around.

And while much early research in robotics focused on using sonar sensors because they were cheap and easy to use, the focus today is on the more challenging, yet richer, vision-based navigation systems.

Similarly, while there is much research on making robotic arms and hands, the difficulty lies in making electronic skin sensitive enough to detect fragile or slippery objects by touch alone. A robot that mimics human speech is also under development.

To encourage advances in these all these fields, it is now common for the robotic community to use contests. These include baseball catching contests, to improve dexterity; goldfish-catching contests, to improve underwater manoeuvrability; even robotic camel jockeying contests have been held, though they were created to replace child jockeys.

The ultimate test perhaps is robot soccer. This is driving development in just about every area of robotics from the ability to run and kick a ball to communicating and demonstrating teamwork. The grand aim is to have a team of humanoid robots that can beat the best human soccer team in the world by 2050.

Until then the question remains that if robots are ever made smart enough to do our ironing will they also be smart enough to refuse to do it for us? Would we suddenly have a robotic-rebellion on our hands?

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