Can you train yourself to get by on less sleep?.


sleepMargaret Thatcher did it. So did Salvador Dali. They survived the day with only a few hours of sleep. The question is whether you can force yourself to do the same.

We waste a third of our lives sleeping – or that’s how some people see it. When there doesn’t seem to be enough hours in the day, you yearn to be like the former British Prime Minister Margaret Thatcher, who was said to get by on just four hours sleep a night, or the artist Salvador Dali who wasted as little time as possible slumbering.

There is a quite a range in the number of hours we like to sleep. As Jim Horne writes in Sleepfaring, 80% of us manage between six and nine hours a night; the other 20% sleep more or less than this. But how easy is it to change your regular schedule? If you force yourself to get out of bed a couple of hours early every day will your body eventually become accustomed to it? Sadly not.

There is plenty of evidence that a lack of sleep has an adverse effect. We do not simply adjust to it – in the short-term it reduces our concentration, and if it’s extreme it makes us confused and distressed, and turns us into such poor drivers that it’s the equivalent of being drunk. The long-term effects are even more worrying. Repeatedly getting less sleep than you need over the course of decades is associated with an increased risk of obesity, diabetes, high blood pressure and cardiovascular disease.

But what about those people who do happily appear to manage on fewer hours than the rest of us?  Why does it not seem to make them ill?

Firstly, you can console yourself with the fact that there are plenty of myths about people’s bold claims. Napoleon allegedly said that sleep was only for weaklings, but in fact he got plenty of shut-eye.

But there are a few very rare individuals who can manage with only five hours sleep a night without experiencing deleterious effects. They are sometimes known as the “sleepless elite”. In 2009, a team led by geneticist Ying-Hui Fu at the University of California San Francisco discovered a mother and daughter who went to bed very late, yet were up bright and early every morning. Even when they had the chance to have a lie-in at the weekend (a tell-tale sign that you are sleep-deprived) they didn’t take it.

Tests revealed that both mother and daughter carried a mutation of a gene called hDEC2. When the researchers tweaked the same gene in mice and in flies, they found that they also began to sleep less – and when mice were deprived of sleep they didn’t seem to need as much sleep in order to catch up again. This demonstrates that genetics play at least some part in your need for sleep; unfortunately the sleepless elites’ enviable state of affairs isn’t available to rest of us, because at the moment we are stuck with the genes we have (that’s my excuse anyway).

But while it might not be possible to train yourself to sleep less,researchers working with the military have found that you can bank sleep beforehand if you plan well in advance. At the Walter Reed Army Institute of Research they had people go to bed a couple of hours earlier than usual every night for a week. When they were subsequently deprived of sleep they didn’t suffer as much as the people who hadn’t had the chance to bank sleep in advance.

This does involve a lot of effort, so in general what you need to do is work out your personal sleep requirement and then try to stick to it. In his bookCounting Sheep Paul Martin describes a method of working this out. You probably need to do it while you’re on holiday because you need to wake up naturally, rather than rely on an alarm clock. Every night for two weeks you go to bed at the same time and see what time you wake up by yourself next morning.  For the first few nights you might well be catching up on missed sleep, but after that the time you wake up gives an indication of the length of your ideal night’s sleep.

 

You might be disappointed to find you need more sleep than you’d hoped, but don’t see it as a waste. This is time spent valuably allowing your body and mind to function at their best during waking hours.  It may use up a third of your life, but it makes the other two thirds so much better. The politician whose sleep patterns inspire me isn’t Margaret Thatcher, but Winston Churchill. He disliked getting out of bed so much that he stayed there working all morning, even receiving visitors in his bedroom.

Source:BBC

 

Dinosaur-killing space rock ‘was a comet’.


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The space rock that hit Earth 65 million years ago and is widely implicated in the end of the dinosaurs was likely a speeding comet.

That is the conclusion of research which suggests the 180km-wide Chicxulub crater in Mexico was carved out by a smaller object than previously thought.

Many scientists consider a large and relatively slow moving asteroid to have been the likely culprit.

Details were outlined at the 44th Lunar and Planetary Science Conference.

But other researchers were more cautious about the results.

“The overall aim of our project is to better characterise the impactor that produced the crater in the Yucatan peninsula [in Mexico],” Jason Moore, from Dartmouth College in New Hampshire, told BBC News.

The space rock gave rise to a global layer of sediments enriched in the chemical element iridium, in concentrations much higher than naturally occurs; it must have come from outer space.

Extra-terrestrial chemistry

However, in the first part of their work, the team suggests that frequently quoted iridium values are incorrect. Using a comparison with another extraterrestrial element deposited in the impact – osmium – they were able to deduce that the collision deposited less debris than has previously been supposed.

The recalculated iridium value suggests a smaller body hit the Earth. So for the second part of their work, the researchers took the new figure and attempted to reconcile it with the known physical properties of the Chicxulub impact.

For this smaller space rock to have produced a 180km-wide crater, it must have been travelling relatively quickly. The team found that a long-period comet fitted the bill much better than other possible candidates.

“You’d need an asteroid of about 5km diameter to contribute that much iridium and osmium. But an asteroid that size would not make a 200km-diameter crater,” said Dr Moore.

“So we said: how do we get something that has enough energy to generate that size of crater, but has much less rocky material? That brings us to comets.”

Dr Moore’s colleague Prof Mukul Sharma, also from Dartmouth College, told BBC News: “You would need some special pleading for an asteroid moving very rapidly – although it is possible. But of the comets and asteroids we have looked at in the skies, the comets are the ones that are moving very rapidly.”

Long-period comets are balls of dust, rock and ice that are on highly eccentric trajectories around the Sun. They may take hundreds, thousands or in some cases even millions of years to complete one orbit.

The extinction event 65 million years ago is now widely associated with the space impact at Chicxulub. It killed off about 70% of all species on Earth in just a short period of time, most notably the non-avian dinosaurs.

The enormous collision would have triggered fires, earthquakes and huge tsunamis. The dust and gas thrown up into the atmosphere would have depressed global temperatures for several years.

Lost in space

Dr Gareth Collins, who researches impact cratering at Imperial College London, described the research by the Dartmouth team as “nice work” and “thought-provoking”.

But he told BBC News: “I don’t think it is possible to accurately determine the impactor size from geochemistry.

“Geochemistry tells you – quite accurately – only the mass of meteoritic material that is distributed globally, not the total mass of the impactor. To estimate the latter, one needs to know what fraction of the impactor was distributed globally, as opposed to being ejected to space or landing close to the crater.”

He added: “The authors suggest that 75% of the impactor mass is distributed globally, and hence arrive at quite a small-sized impactor, but in reality this fraction could be lower than 20%.”

That could keep the door open for a bigger, more slowly moving asteroid.

The authors accept this point, but cite recent studies suggesting mass loss for the Chicxulub impact was between 11% and 25%.

In recent years, several space objects have taken astronomers by surprise, serving as a reminder that our cosmic neighbourhood remains a busy place.

On 15 February this year, 2012 DA14 – an asteroid as large as an Olympic swimming pool – raced past the Earth at a distance of just 27,700km (17,200mi). It had only been discovered the previous year.

And on the same day, a 17m space rock exploded over Russia’s Ural mountains with an energy of about 440 kilotonnes of TNT. About 1,000 people were injured as the shockwave blew out windows and rocked buildings.

Some 95% of the near-Earth objects larger than 1km have been discovered. However, only about 10% of the 13,000 – 20,000 asteroids above the size of 140m are being tracked.

There are probably many more comets than near-Earth asteroids, but Nasa points out they spend almost all of their lifetimes at great distances from the Sun and Earth, so that they contribute only about 10% to the census of larger objects that have struck the Earth.

Source:BBC

Cold-tolerant wasp spiders spread to northern Europe.


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Temperature tolerance is key to the spread of wasp spiders into northern Europe, according to scientists.

Since the 1930s the distinctive spiders have expanded their range from the Mediterranean coast to Norway.

Researchers in Germany traced the population boom to breeding between the native European spiders and an isolated colony living near the Black Sea.

Molecular Ecology reports the genetic mixing resulted in generations rapidly adapting to living in colder climates.

Wasp spiders (Argiope bruennichi) are commonly named for their bright, striped abdomens and were recently recorded by the Woodland Trust in Usk, south Wales for the first time.

The first official records of this conspicuous species in the UK were made in the 1920s.

Henrik Krehenwinkel from the Max Planck Institute for Evolutionary Biology, Germany, analysed the DNA of spiders caught across their current range, and museum specimens to understand more about their evolutionary history.

Piecing together the genetic puzzle, he found that the spiders diverged after the last ice age: part of the population stayed on the Mediterranean while a colony headed east to Central Asia.

While these eastern populations adapted to live in climates as diverse as the tropical south of Japan and cold south-eastern Siberia, the spiders in the Mediterranean remained limited to warm areas.

But, according to the research, rising temperatures across the continent in the last century allowed the Mediterranean spiders to join up and breed with a previously isolated Black Sea population.

“This possibly restored genetic variation within a few generations and allowed for rapid adaptation,” said Mr Krehenwinkel.

He theorised that the novel combination of genes resulted in new physical characteristics that helped spiders to survive in different environments.

Out in the cold

To test the whether these more northerly spiders adapted a different temperature tolerance than Mediterranean populations, the PhD student analysed how they reacted when moved into one another’s habitats.

Southern spiders could not survive the freezing temperatures in the north, and their counterparts suffered from heat stress in the south.

Mr Krehenwinkel explained that the eastern population had adapted to cooler temperatures and this was passed on to European spiders in the population boom.

The result was the rapid adaptation of hardier offspring that could settle further north than their predecessors.

The spiders found in northern Europe have smaller bodies and are not seen in the coldest months of the year.

Scientists attribute both traits to seasonal changes which do not affect southern species. Spiders found in northern Europe “overwinter”, meaning their young are buried during the coldest months; emerging in spring.

The spiders then have limited warm months in which they can mature, which restricts how large they can grow before they reproduce in the autumn and the cycle begins again.

Mr Krehenwinkel described the hatchlings as “highly dispersive”, commenting that they can cover huge distances via a method known as “ballooning”: riding the breeze on a special parachute made of gossamer silk threads.

“By aerial dispersal, little spiders can cover distances of several hundred kilometres,” he told BBC Nature.

“Members of different genetic lineages can thus quickly track warming climate, which increases the likelihood of contact.”

Source:BBC

Three-person IVF moves closer in UK.


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The UK has moved closer to becoming the first country to allow the creation of babies from three people.

The Human Fertilisation and Embryology Authority (HFEA) has advised the government that there is no evidence the advanced forms of IVF were unsafe.

The fertility regulator’s public consultation also showed “general support” for the idea as the benefits outweighed the risks.

A final decision on whether to press ahead rests with ministers.

If the techniques were approved it could help a handful of families each year. Around one in 6,500 children develop serious “mitochondrial disorders” which are debilitating and fatal.

Research suggests that using mitochondria from a donor egg can prevent the diseases.

However, it would result in babies having DNA from two parents and a tiny amount from a third donor.

Concerns have been raised both about the safety and the ethics of creating such babies.

The results of a public consultation at the end of 2012 showed there was support for the idea.

Prof Neva Haites, who was on the expert panel supervising the consultation, said: “Broadly speaking the public was in favour of these novel techniques being translated into treatments.

“They felt that any ethical concerns were outweighed by potential benefits.”

One of the main issues raised was of a “slippery slope” which could lead to other forms of genetic modification.

‘Power stations’

Mitochondria are the tiny biological power stations that give energy to nearly every cell of the body.

Defects can leave the body starved of energy, resulting in muscle weakness, blindness, heart failure and death in the most extreme cases.

The cigar-shaped mitochondria are passed only from mother to child. A father does not pass on his mitochondria through his sperm.

Scientists have devised two techniques that allow them to take the genetic information from the mother and place it into the egg of a donor with healthy mitochondria. It is like taking two fried eggs and switching the yolks.

The result is a baby with genetic information from three people, as mitochondria have their own genes in their own DNA.

The implications are not just for the couple and the child. If the therapy was performed it would have ramifications through the generations as scientists would be altering human genetic inheritance.

‘Recommendations’

The HFEA has advised that any changes to the law should be only for the modification of mitochondria to overcome serious diseases and that there should still be a ban on changes to the main nuclear DNA, which contains the vast majority of a person’s genetic code.

It also recommended continuing research and that any children born through these techniques, and possible the children’s children, be monitored closely.

Any time soon?

These therapies using sperm and eggs from three people are not yet ready to be performed in the clinic. However, it is thought that scientists in the UK and the US are getting close to the point where it will be possible.

Prof Robin Lovell-Badge, part of the expert panel analysing the science, said there was “still no evidence to suggest the techniques are unsafe,” but he said further experiments were needed for reassurance.

“Safety is absolutely not a black and white issue. In reproductive medicine in particular it is not possible to be absolutely certain about the consequences of any new treatment until children are born.

“Someone at some point is going to have to take the brave decision to go ahead with it.”

Some of the researchers involved believe they may be ready to make the leap in three to five years – if everything goes to plan, something which is by no means certain.

There was vigorous discussion at the HFEA Open Meeting, where the advice to ministers was agreed, around issues of identification. In sperm and egg donation the donor is identified.

The meeting agreed to advise ministers that there should be no right for the child to know the identity of the donor, however, the HFEA will tell ministers that public opinion was mixed.

Mr Hossam Abdalla, clinical director of the Lister Fertility Clinic in London, told the meeting: “If a child wants to know about that, why are we so restrictive… why are we telling them we they can’t have this access?”

‘Astounded’

Prof Lisa Jardine, chairwoman of the HFEA, said the UK was in one of the most advanced positions in the world.

“Other countries are astounded that we’re this far on in the discussions,” she said.

However, she pointed out the techniques would be used only for mitochondrial disorders: “This is not a Rubicon or a slippery slope.”

One of the pioneers of the field, Prof Doug Turnbull, from Newcastle University, said: “The techniques we are working on could help hundreds of women have healthy children.”

He said more research was required, but it was now “crucial” that the government approved the techniques in the UK.

The Department of Health said mitochondrial diseases could have a “devastating impact” on families and it would consider the HFEA’s advice.

Making three-person IVF legal would not require a new act of Parliament, but would require a vote in both the Commons and the Lords.

Speaking after the meeting Dr David King, the director of Human Genetics Alert, said: “Historians of the future will point to this as the moment when technocrats crossed the crucial line, the decision that led inexorably to the disaster of genetically engineered babies and consumer eugenics.

“This was the moment at which they casually tossed the bioethical consensus of the last 30 years into the trash. And for what?

“Not so mothers could avoid having sick babies, because they could do that already, through egg donation. It was so that a few dozen mothers who insisted they must be genetically related to their child could be satisfied.”

Source:BBC

 

 

 

 

 

‘Most family doctors’ have given a patient a placebo drug.


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Most family doctors have given a placebo to at least one of their patients, survey findings suggest.

In a poll, 97% of 783 GPs admitted that they had recommended a sugar pill or a treatment with no established efficacy for the ailment their patient came in with.

The PLOS One study authors say this may not be a bad thing – doctors are doing it to help, not to deceive patients.

The Royal College of GPs says there is a place for placebos in medicine.

But they warn that some sham treatments may be inappropriate and could cause side effects or issues such as drug resistance.

For example, one of the placebo treatments identified in the study was antibiotics for suspected viral infections.

 “Start Quote

This is not about doctors deceiving patients”

Dr Jeremy HowickThe study’s co-author

Antibiotics are powerless against viruses and doctors are told not to use them.

About one in 10 of the GPs in the study said they had given a patient a sugar pill or an injection of salty water rather than a real medicine at some time in their career.

One in 100 of them said they did this at least once a week.

‘Offering reassurance’

Almost all of the GPs said they had provided patients with treatments, like supplements, probiotics and complementary medicines, that were unproven for their medical condition. Three-quarters said they offered unproven treatments on a daily or weekly basis.

Dr Jeremy Howick, co-author of the study that was carried out by the University of Oxford and the University of Southampton, said: “This is not about doctors deceiving patients.

The power of placebo

The placebo effect – when the patient feels better despite taking a medicine with no active ingredient – can be surprisingly strong.

One study even found patients with irritable bowel syndrome reported improvements despite knowing they were taking a dummy pill.

And its not just pills, fake acupuncture has been shown to reduce the severity of headaches and migraines.

The effect is based on the patient’s expectation of a cure and seems to work best for subjective measures such as pain.

The size, colour, and branding of placebo treatments have all been shown to influence ‘effectiveness’.

The placebo is the backbone of medical research enabling doctors to distinguish between real and expected or perceived effects of treatment.

But when it comes to their use in general medicine some believe their use can damage the doctor-patient relationship.

The question is whether the patient minds as long as they have their ‘cure’.

“The study shows that placebo use is widespread in the UK, and doctors clearly believe that placebos can help patients.”

The GPs in the study said they used placebos either because patients requested treatment or to reassure patients.

Half said they told their patients that the therapy had helped other patients without specifically telling them that they were prescribing a placebo.

Dr Clare Gerada, chairwoman of the Royal College of GPs, said it was perfectly acceptable to use a placebo as long as it did not cause harm and was not expensive.

“Lots of doctors use them and they can help people.

“If you think about it, a kiss on the cheek when you fall over is a placebo.

“But there are risks. Not all of the placebo treatments that the researchers looked at in this study are inert. If you take too many vitamins, for example, some can cause harm.”

She said fobbing off patients with an ineffectual treatment was never acceptable. “But admitting to your patient that you do not know exactly what is going on, but that a therapy might help is.”

Source:BBC

 

Grandparents ‘may relay autism risk to grandchildren’.


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The risk of developing autism may be passed on through – and not just to – future generations, researchers say.

The international study suggests older fathers are more likely to have grandchildren with autism than their younger counterparts.

The mechanism is unclear but it is thought they may transmit “silent mutations” to their grandchildren.

But experts have urged caution, stressing autism is the result of many different factors.

The study, looking at almost 6,000 people with the condition, is published in the journal Jama Psychiatry.

According to the National Autistic Society, more than one in every 100 people in the UK have the condition.

Previous studies suggested older fathers may be at greater risk of having children with autism than younger dads.

But the team of UK, Swedish and Australian researchers say this is one of the first pieces of evidence to show the risk can be passed on through – rather than just straight to – future generations.

Continue reading the main story

“Start Quote

We can’t put exact figures on this risk yet. But most children born to older fathers and grandfathers grow up fine”

Dr Avi ReichenbergCo-author of study

The “silent mutations” – changes in genetic material – are likely to have no obvious impact on older fathers’ own children, but they may build up through subsequent generations, or interact with other genes and environmental factors, to increase the chance of their grandchildren developing the condition, the researchers say.

Using national databases from Sweden they studied almost 6,000 people diagnosed with the condition and more than 30,000 without, tracking their parents’ and grandparents’ ages.

They found men who had a daughter when aged 50 or older were 1.79 times more likely to have a grandchild with autism, compared to men who fathered children when aged between 20-24.

And those who had a son when 50 years of age or older were 1.67 times more likely to have a grandchild with the condition.

‘Complex causes’

But they say this study should not discourage older people from having children as though the risk is increased, it still remains small.

Co-author of the study, Dr Avi Reichenberg from King’s College Institute of Psychiatry, told the BBC: “It is about choices. If you choose to have a child at an old age there might be consequences. This is something everyone should consider.

Autism

 

  • People with autism usually have difficulties with social communication, social interaction and social imagination
  • It is a spectrum condition meaning while all people with autism share certain difficulties, the condition affects them differently
  • There are more than 500,000 people with autism in the UK – that’s one in every 100
  • There is no cure, but there are a range of interventions available

Source: NHS Choices

“Unfortunately we can’t put exact figures on this risk yet. But most children born with older fathers and grandfathers grow up fine.

“And as scientists this type of information helps open doors to understanding more about the condition.”

Caroline Hattersley, of The National Autistic Society, said: “While this research is useful in aiding our understanding of autism’s complex causes, it should be treated with caution.

“Autism is thought to be the result of many different underlying physical and genetic factors.

“The study is not definitive, as we know that many people who had children at a young age also have grandchildren with the condition. We therefore urge parents and those thinking of starting a family not to be concerned about the findings.”

Dr Terry Brugha, professor of psychiatry at the University of Leicester who was not involved in the study, said: “This is a solid piece of work and the findings are plausible. But as a grandparent or parent-to-be this is not something to be overly concerned about.

“We are at the early stages of research and this study gives us a slightly deeper understanding of what is going on in the background.”

Source:BBC