All sewn up

WEARABLE and implantable medical gadgets are a promising technology. By continuously collecting information from patients they make it easier to diagnose and treat whatever the problem may be. But most of the sensors in such devices have to lie flat against the body. That limits what they can do.

Now a team of researchers are trying to use one of humanity’s oldest technologies to do better. As they report in Microsystems & Nanoengineering, Sameer Sonkusale at Tufts University, in Massachusetts, and his colleagues, propose to turn threads, of the sort spun to make clothes, into sensors.

Thread has many advantages. It is cheap, flexible and mostly tolerated by human bodies. Most pertinently, doctors have plenty of experience, via the practice of suturing, of sewing it into bodily tissues. Doing that with smart thread would allow a more detailed overview of what is happening than any skin-mounted sensor could.

Turning yarn into sensors requires clever chemistry. Electrodes for recording mechanical or chemical activity can be…Continue reading
Source: Economist

Atoms and the voids

There is indeed plenty of room at the bottom

WHAT if “we can arrange the atoms the way we want; the very atoms, all the way down”? So asked the physicist Richard Feynman in an influential 1959 lecture called “There’s Plenty of Room at the Bottom”. This manipulation would mean that information, like text, could be written using atoms themselves. Feynman predicted that the entire “Encyclopædia Britannica” could be written on the head of a pin.

Three decades later, a group of scientists at IBM managed exactly that. They were able to write the firm’s name using 35 xenon atoms resting on a sheet of nickel—the first demonstration of precise atomic placement. Individual atoms, though, tend to jiggle around. They jiggle less at lower temperatures, so to keep the atoms in place, the researchers cooled them to -269ºC, just 4ºC above absolute zero, the coldest temperature physically possible. This was so costly that writing more than three letters did not make sense.

Now a team of researchers led by Sander Otte at Delft University of Technology, in the Netherlands, <a…Continue reading
Source: Economist

Scientists pave the way for large-scale storage at the atomic level

WHAT if “we can arrange the atoms the way we want; the very atoms, all the way down”? So asked the physicist Richard Feynman in an influential 1959 lecture called “There’s Plenty of Room at the Bottom.” This manipulation would mean that information, like text, could be written using atoms themselves. In his speech, Feynman predicted that the entire Encyclopædia Britannica could be written on the head of a pin.

Just over three decades later, a group of scientists at IBM managed exactly that. They were able to write their company’s name using 35 xenon atoms resting on a sheet of nickel—the first demonstration of precise atomic placement. Individual atoms, though, tend to jiggle around. They jiggle less as the temperature drops, so to keep the atoms in place, the researchers had to cool them to -269ºC, just 4ºC above absolute zero, the coldest temperature physically possible. That was so expensive that writing more information than three letters did not make sense.

Now, a team of researchers led by Sander Otte at Delft University of Technology, in the Netherlands, have devised a better way to keep the atoms in place, paving the…Continue reading
Source: Economist

What’s the matter with the universe?

Source: Economist

Shell shock

Opaque results or translucent answers?

UNDERSTANDING past climates is crucial to understanding future ones, and few things have been more important to that historical insight than fossil foraminifera. Forams, as they are known, are single-celled marine creatures which grow shells made of calcium carbonate. When their owners die, these shells often sink to the seabed, where they accumulate in sedimentary ooze that often gets transformed into rock.

For climate researchers, forams are doubly valuable. First, regardless of their age, the ratio within them of two stable isotopes of oxygen (¹⁶O and ¹⁸O) indicates what the average temperature was when they were alive. That is because different temperatures cause water molecules containing different oxygen isotopes to evaporate from the sea at different rates; what gets left behind is what shells are formed from. Second, for those forams less than about 40,000 years old, the ratio of an unstable, and therefore radioactive, isotope of carbon (¹⁴C) to that of stable ¹²C indicates when they were alive. That means the rock they are in can be…Continue reading
Source: Economist

Computer says: oops

NOBODY knows how the brain works. But researchers are trying to find out. One of the most eye-catching weapons in their arsenal is functional magnetic-resonance imaging (fMRI). In this, MRI scanners normally employed for diagnosis are used to study volunteers for the purposes of research. By watching people’s brains as they carry out certain tasks, neuroscientists hope to get some idea of which bits of the brain specialise in doing what.

The results look impressive. Thousands of papers have been published, from workmanlike investigations of the role of certain brain regions in, say, recalling directions or reading the emotions of others, to spectacular treatises extolling the use of fMRI to detect lies, to work out what people are dreaming about or even to deduce whether someone truly believes in God.

But the technology has its critics. Many worry that dramatic conclusions are being drawn from small samples (the faff involved in fMRI makes large studies hard). Others fret about over-interpreting the tiny changes the technique picks up. A deliberately provocative paper published in 2009, for example, found apparent activity in the brain of a…Continue reading
Source: Economist