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Sleeping pills could actually IMPROVE your memory, claims controversial new research.

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  • Researchers claim that the zolpidem in some sleeping pills enhances the brain’s ability to build-up memories
  • They say the findings could help in the development of treatments for Alzheimer’s and dementia
  • Contradicts previous research which found the drug may actually CAUSE memory loss

 

 

 

Taking sleeping tablets could help improve your memory, according to controversial new research.

 

A team of researchers claim to have discovered the mechanism that enables the brain to build-up memories – and say they found that a commonly prescribed sleeping tablet containing zolpidem enhances this process.

 

They hope the discovery could lead to new sleep therapies that could improve memory for ageing adults and those with dementia, Alzheimer’s and schizophrenia.

 

The findings contradict a wealth of previous research that has suggested that sleeping pills can have devastating effects on health, including memory.

 

The new research claims to have demonstrated, for the first time, the critical role that sleep spindles play in consolidating memory in the hippocampus.

 

Sleep spindles are bursts of brain activity that last for a second or less during sleep.

 

Earlier research found a link between sleep spindles and the consolidation of memories that depend on the hippocampus, the part of the brain that is involved in memory forming, organising, and storing.

 

The research team say they showed that the drugs could significantly improve that process, far more than sleep alone.

 

Lead author of the study, Dr Sara Mednick, a psychologist from the University of California Riverside, said: ‘We found that a very common sleep drug can be used to increase memory.

 

‘This is the first study to show you can manipulate sleep to improve memory.

 

‘It suggests sleep drugs could be a powerful tool to tailor sleep to particular memory disorders.’

 

But previous research has suggested that sleeping pills taken by more than a million Britons significantly increase the risk of dementia.

 

Pensioners who used benzodiazepines – which include temazepam and diazepam – are 50 per cent more likely to succumb to the devastating illness, a Harvard University study found.

 

They work by changing the way messages are transmitted to the brain, which induces a calming effect but scientists believe that at the same time they may be interfering with chemicals in the brain known as neurotransmitters, which may be causing dementia.

 

The new study tested normal sleepers, who were given varying doses of sleeping pills and placebos, allowing several days between doses to allow the drugs to leave their bodies.

 

Researchers monitored their sleep, measured sleepiness and mood after napping, and used several tests to evaluate their memory.

 

They found that zolpidem significantly increased the density of sleep spindles and improved verbal memory consolidation.

 

Dr Mednick said: ‘Zolpidem enhanced sleep spindles in healthy adults producing exceptional memory performance beyond that seen with sleep alone or sleep with the comparison drug.

 

‘The results set the stage for targeted treatment of memory impairments as well as the possibility of exceptional memory improvement above that of a normal sleep period.’

 

Dr Mednick also hopes to study the impact of zolpidem on older adults who experience poor memory because individuals with Alzheimer’s, dementia and schizophrenia are known experience decreases in sleep spindles.

 

Dr Mednick, who began studying sleep in the early 2000s, says sleep is a very new field of research and its importance is generally not taught in medical schools.

 

‘We know very little about it,’ she said.

 

‘We do know that it affects behaviour, and we know that sleep is integral to a lot of disorders with memory problems.

 

‘We need to integrate sleep into medical diagnoses and treatment strategies. This research opens up a lot of possibilities.’

 

Source: http://www.dailymail.co.uk

 

 

 

Metal Oxide Chips Show Promise as Transistors.

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Materials that flip from insulator to conductor could make more energy-efficient transistors, although the metals are not yet close to competing with silicon

The switches in most electronic circuits are made of silicon, one of the commonest elements. But their successors might contain materials that, for now, are lab-grown oddities: strongly correlated metal oxides.

The allure of these materials lies in the outer shells of electrons surrounding their metal atoms. The shells are incomplete, leaving the electrons free to participate in coordinated quantum-mechanical behavior. In some materials, electrons pair up to produce super­conductivity, or coordinate their spins to produce magnetism. Other materials can switch from being an insulator to a conductor.

Unlike transitions to superconductivity, which happen as temperatures approach absolute zero, the insulating-to-conducting transition typically happens as temperature increases, and sometimes occurs near room temperature. That has raised hopes that metal oxides could be used instead of silicon to make transistors. A spate of results is now making that look feasible. “People are interested in seeing if oxides can make it to applications,” says Manuel Bibes, a physicist at the Joint Physics Unit in Palaiseau, France, which is run by the French National Research Center and electronics company Thales.

Metal oxide transistors have the potential to consume less power than silicon switches, because the phase transition frees electrons from their localized state near each atom, without moving them through the bulk material. By contrast, silicon switches work by pulling electrons through the material to a channel where they conduct current (see ‘Go with the flow’).

In the past 5–10 years, researchers have succeeded in growing high-quality thin films of the metal oxides — overcoming one of the major barriers to applications. In July 2012, for example, a group in Japan reported that it had deposited a thin film of vanadium dioxide that underwent a phase transition in response to an applied electric field — proof that the material could be used as an electronic switch.

And last month, a group led by Shriram Ramanathan, a materials scientist at Harvard University in Cambridge, Massachusetts, addressed a fabrication challenge by growing a thin film of samarium nickelate on top of a substrate made of silicon and silicon dioxide.

The nickelate was deposited at a relatively low temperature that did not disturb the underlying silicon layers, raising the possibility of manufacturing metal oxides on top of silicon wafers to form three-dimensional chips, says Andrew Millis, a solid-state theorist at Columbia University in New York. Not only would that allow computing power to be packed much more densely, says Millis, but it would also permit metal oxide switches to be built on top of existing circuit architectures.

Other groups are trying to understand the nature of the phase transition. In January, Ivan Schuller, a solid-state physicist at the University of California, San Diego, and his colleagues showed that in vanadium oxide, the transition is in large part caused by micrometer-scale heating by the applied electric field.

Some point to Schuller’s work as evidence that metal oxides will never make fast switches, because heating effects are usually quite slow. But Ramanathan says that his own measurements on vanadium oxide demonstrate that the phase transition is quite fast — less than a few nanoseconds — and that it should not hinder applications.

Some physicists are finding further examples of potentially useful materials. Bernhard Keimer at the Max Planck Institute for Solid State Research in Stuttgart, Germany, alternates thin layers of metal oxides to form composites that often turn out to have serendipitous properties. His group layered conducting lanthanum nickelate and insulating lanthanum aluminate and found that the composite underwent a transition between the two properties.

The highest phase-transition temperature for the composite was 150 kelvin above absolute zero — too low for practical applications. But the group is now trying to replicate the phenomenon in other materials that might have higher transition temperatures.

Sandip Tiwari, an applied physicist at Cornell University in Ithaca, New York, acknowledges that metal oxides are not yet close to competing with silicon. But given recent progress, he feels that researchers need to start trying to implement them in devices. That way, he says, all the properties needed for a good transistor will be developed in tandem. “If you just look at whatever property is your favorite, you won’t get them all.”

Source: Scientific American.

Printing a human kidney.

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Surgeon Anthony Atala demonstrates an early-stage experiment that could someday solve the organ-donor problem: a 3D printer that uses living cells to output a transplantable kidney. Using similar technology, Dr. Atala’s young patient Luke Massella received an engineered bladder 10 years ago; we meet him onstage. Talk recorded 3 March 2011.

About the Speaker

Anthony Atala asks, “Can we grow organs instead of transplanting them?” His lab at the Wake Forest Institute for Regenerative Medicine is doing just that – engineering over 30 tissues and whole organs. Anthony Atala is the director of the Wake Forest Institute for Regenerative Medicine, where his work focuses on growing and regenerating tissues and organs. His team engineered the first lab-grown organ to be implanted into a human – a bladder – and is developing experimental fabrication technology that can “print” human tissue on demand.

In 2007, Atala and a team of Harvard University researchers showed that stem cells can be harvested from the amniotic fluid of pregnant women. This and other breakthroughs in the development of smart bio-materials and tissue fabrication technology promises to revolutionize the practice of medicine.

Source: BBC.

The First Book To Be Encoded in DNA.

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Two Harvard scientists have produced 70 billion copies of a book in DNA code –and it’s smaller than the size of your thumbnail.
Despite the fact there are 70 billion copies of it in existence, very few people have actually read the book Regenesis: How Synthetic Biology Will Reinvent Nature and Ourselves in DNA, by George Church and Ed Regis. The reason? It is written in the basic building blocks of life: Deoxyribonucleic acid, or DNA.

Church, along with his colleague Sriram Kosuri, both molecular geneticists from the Wyss Institute for Biomedical Engineering at Harvard, used the book to demonstrate a breakthrough in DNA data storage. By copying the 53,000 word book (alongside 11 jpeg images and a computer program) they’ve managed to squeeze a thousand times more data than ever previously encoded into strands of DNA, as reported in the August 17 issue of the journal Science. (To give you some idea of how much information we’re talking about, 70 billion copies is more than three times the total number of copies for the next 200 most popular books in the world combined.)

Part of DNA’s genius is just how conspicuously small it is: so dense and energy efficient that one gram of the stuff can hold 455 billion gigabytes. Four grams could in theory hold ever scrap of data the entire world produces in a year. Couple this with a theoretical lifespan of 3.5 billion years and you have a revolution in data storage, with wide ranging implications for the amount of information we could record and store.

Don’t expect your library to transform from paperbacks to vials of DNA anytime soon though. “It took a decade to work out the next generation of reading and writing of DNA – I’ve been working on reading for 38 years, and writing since the 90s,” Church tells TIME.

The actual work of encoding the book into DNA and then decoding it and copying it only took a couple weeks. “I did it with my own two hands!” says Dr. Church, “which is very rare to have that kind of time to spend doing something like this.” Church and Kosuri took a computer file of Regenesis and converted it into binary code — strings of ones and zeroes. They then translated that code into the basic building blocks of DNA. “The 1s stand for adenine (A) or cytosine (C) and the zero for guanine (G) and thymine (T),” says Kosuri.  Using a computer program, this translation was simple.

While the future implications and applications are not yet clear, the DNA storage industry is moving at an incredible speed. “Classical electronic technology is moving forward something like 1.5 fold per year,” says Dr. Church, “whereas reading and writing DNA is improving roughly ten fold per year. We’ve already had a million-fold improvement in the past few years, which is shocking.”

Given that the genomics field has attracted its fair share of criticism — witness, for example, the firestorm that greeted biologist Craig Venter and his colleagues when they created the first synthetic cell in 2010 — there are ethical questions to address. Dr. Church and co-author Ed Regis have decided not to include a DNA insert of the book with the actual paper copy when it comes out in October because of this sensitivity.

“We’re always trying to think proactively about the ethical, social and economic implications in this line of work,” says Dr. Church. He explains that the risks are relatively small, but both he and Dr. Kosuri mention that if it is possible to encode a book using DNA encode, it is also theoretically possible to encode a virus–though this would be a far-fetched scenario.

“The chances that something bad will come out of this is so small,” says Dr. Kosuri. “If someone really nefarious wanted to make a virus they would have to use a much larger chunk of DNA to encode function.”

Why make 70 billion copies of the book? “Oh that was a bit of fun,” says Dr. Church. “We calculated the total copies of the top 200 books of all time, including A Tale of Two Cities and the Bible and so on, and they add up to about 20 billion. We figured we needed to go well beyond that.”

Source: Time

 
Read more: http://newsfeed.time.com/2012/08/20/the-first-book-to-be-encoded-in-dna/#ixzz246tbt1He

 

A Dash of Color Creates camouflage for Spineless Robots.

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Late last year, Harvard University chemists and materials scientists introduced a robot whose rubbery appendages fly—or, more accurately, crawl—in the face of conventional automatons. These invertebrate-inspired albino bots relied on elastic polymers and pneumatic pumps to imitate the movements of worms, squid and starfish. Now these squishy quadrupeds can be pumped with a variety of dyes, enabling them to either blend in or stand out from their environments.

In addition to stretching the boundaries of how robots are designed, built and operated, adding color could help scientists better understand why certain creatures may have evolved to their current shape, color and capabilities, according to the researchers, led by chemist and materials scientist George Whitesides. In the August 17 issue of Science, the researchers describe using 3-D printers to create silicone robots whose different layers contain microchannels through which liquids can flow in a variety of patterns. Heated or cooled solutions pumped into these channels enabled the researchers to create thermal camouflage, while fluorescent fluids produced glow-in-the-dark

These five-centimeter-thick bots, each of which looks like a pair of Ys joined at the stem, mimic natural movement without the need for complex mechanical components and assembly. They also demonstrate the value of considering simple animals when looking for inspiration for robots and machines, the researchers say.

The shape-shifting robot features an upper, flexible layer designed with a system of channels through which air can pass. A second layer is made of a more rigid polymer. The researchers place the top, actuating layer onto the bottom, strain limiting/sealing layer with a thin coating of silicone adhesive. Air pumped into different valves in the upper layer causes them to inflate and bend the robot into different positions. For example, the robot can lift any one of its four legs off the ground and leave the other three legs planted to provide stability, depending on which channels are inflated.

In the following video, Stephen Morin, a Harvard post-doctoral fellow in chemistry and chemical biology and lead author of the paper, demonstrates how the flexible robot can change color depending upon its surroundings.

Source: Scientific American