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Technology IMPLANTS that encourage bone regrowth could one day be printed using ink-jet technology. In the current edition of the journal Advanced Materials (http://tinyurl.com/2ydraj) a team at McGill University in Montreal, Canada, reveal how it can be done. They “print” droplets of a tricalcium phosphate suspension, layer by layer on a hydroxyapatite surface. These minerals reacts to form brushite, a calcium phosphate that hardens into a porous 3D scaffold. This slowly dissolves in the body to be replaced by real bone. Better still, the team, led by Jake Barralet, has successfully encouraged a network of blood vessels to grow in their implants. When an implant was tested in mice, the use of a growth factor called VEGF caused extensive vascularisation. EVER heard of the ruthenium rush, the bismuth bonanza or the indium stampede? Demand for cellphones and flat-screen TVs is depleting global supplies of a host of uncommon metals. Indium is built into a billion consumer devices a year, for instance in phone displays, and prices have soared. Some estimates say reserves could run 30 thousand Estonians, or 3.5 per cent of the country’s voters, cast their ballot online last week in the world’s first internet election Brake lights warn that a car in front is slowing down but they give no indication of how sharply it is braking. Respond too slowly and you could slam straight into it. To try to prevent this, particularly at night and in poor weather, Zhonghai Li and Paul Milgram at the University of Toronto in Canada propose fitting cars with brake lights that grow larger the harder the driver brakes. They began by experimenting with novel brake-light configurations in driving simulators, to see what changes would indicate most clearly how heavily a vehicle is braking. The arrangement they eventually decided on was a triangle, with an upper brake light placed slightly above two lights on either side. When the driver just touches the brakes, the lights form a small triangle close to the centre of the car. As braking gets heavier, all three lights get bigger, and those to the left and right also move outwards in proportion to the braking force. With the brakes fully applied, the lights get larger still and move right out to the edge of the car. In simulator tests with 40 volunteer drivers, the scheme showed the biggest benefits in very poor visibility, the researchers will report in an upcoming edition of the International Journal of Human-Computer Studies. Rear-end collisions accounted for 30 per cent of all US road crashes in 2003, including 5 per cent of fatal collisions, according to government figures. Shape-shifting brake lights could be built into cars using low-power LED arrays, say the researchers, who hope to interest car makers in the idea. TAIL LIGHTS GROW IN THE DARK out within five years. Bismuth, used in lead-free solder, has doubled in price in two years, while the price of ruthenium, used in resistors and disc drives, has risen sevenfold in a year. To meet demand, tech firms must mine the growing mountains of electronic waste to recover the materials, says Rüdiger Kühr of the United Nations University in Tokyo, which this week launched a global e-waste initiative. “The recycling of trace metals is essential to ongoing production,” he says. Fatal bushfires in Australia have had scientists calling for virtual reality systems that would let people “experience” the conflagrations and react more rationally in the face of their soaring flames and booming noise. Now the University of Nevada, Reno, has developed such a system, called VRFire, which lets users wearing position trackers and surrounded by video screens explore 3D bush terrain with realistic visuals and the sound of spreading wildfires (http://tinyurl.com/36lumm). A gadget that shrieks if a driver begins to doze at the wheel has been developed by Revex of Japan. The firm’s $10 Drowse Prevention Alarm is built into a small earpiece and contains a tilt sensor and an audio alarm. If the wearer’s head tilts forward just 10 degrees, the sensor activates the alarm in case they are nodding off. GIZMO In US Department of Homeland Security field trials 10 of the 14 robots tested experienced communication problems due to radio interference from other robots ROBOT INTERFERENCE Conflicting radio signals between robots could hamper urban search and rescue operations Journalist Noam Cohen on the anger amongst Wikipedia editors after the unmasking of “Essjay”, a trusted editor who had claimed to be a tenured university lecturer in religion. In fact he is a 24-year-old ex-student with a close interest in Justin Timberlake’s musical career (The New York Times, 5 March) “The wisdom of the crowd became the fury of the crowd” CREATAS SOURCE: AFP SOURCE: NIST Bone up with an ink-jet printer TVs put squeeze on minor metals www.newscientist.com 10 March 2007 | NewScientist | 25 Safer braking ahead

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Page 1: Bone up with an ink-jet printer

Technology

IMPLANTS that encourage

bone regrowth could one day be

printed using ink-jet technology.

In the current edition of the

journal Advanced Materials (http://tinyurl.com/2ydraj) a team

at McGill University in Montreal,

Canada, reveal how it can be

done. They “print” droplets of a

tricalcium phosphate suspension,

layer by layer on a hydroxyapatite

surface. These minerals reacts

to form brushite, a calcium

phosphate that hardens into a

porous 3D scaffold. This slowly

dissolves in the body to be

replaced by real bone.

Better still, the team, led by

Jake Barralet, has successfully

encouraged a network of blood

vessels to grow in their implants.

When an implant was tested in

mice, the use of a growth factor

called VEGF caused extensive

vascularisation.

EVER heard of the ruthenium

rush, the bismuth bonanza or

the indium stampede?

Demand for cellphones and

flat-screen TVs is depleting global

supplies of a host of uncommon

metals. Indium is built into a

billion consumer devices a year,

for instance in phone displays,

and prices have soared. Some

estimates say reserves could run

30thousand Estonians, or 3.5

per cent of the country’s

voters, cast their ballot online

last week in the world’s first

internet election

Brake lights warn that a car in front

is slowing down but they give no

indication of how sharply it is braking.

Respond too slowly and you could

slam straight into it. To try to prevent

this, particularly at night and in

poor weather, Zhonghai Li and Paul

Milgram at the University of Toronto in

Canada propose fitting cars with brake

lights that grow larger the harder the

driver brakes.

They began by experimenting

with novel brake-light configurations in

driving simulators, to see what changes

would indicate most clearly how heavily

a vehicle is braking. The arrangement

they eventually decided on was a

triangle, with an upper brake light

placed slightly above two lights on

either side. When the driver just touches

the brakes, the lights form a small

triangle close to the centre of the car.

As braking gets heavier, all three lights

get bigger, and those to the left and right

also move outwards in proportion to

the braking force. With the brakes fully

applied, the lights get larger still and

move right out to the edge of the car.

In simulator tests with 40 volunteer

drivers, the scheme showed the biggest

benefits in very poor visibility, the

researchers will report in an upcoming

edition of the International Journal of Human-Computer Studies.

Rear-end collisions accounted for

30 per cent of all US road crashes in 2003,

including 5 per cent of fatal collisions,

according to government figures.

Shape-shifting brake lights could be

built into cars using low-power LED

arrays, say the researchers, who hope

to interest car makers in the idea.

TAIL LIGHTS GROW IN THE DARK

out within five years. Bismuth,

used in lead-free solder, has

doubled in price in two years,

while the price of ruthenium,

used in resistors and disc drives,

has risen sevenfold in a year.

To meet demand, tech firms

must mine the growing mountains

of electronic waste to recover the

materials, says Rüdiger Kühr of the

United Nations University in Tokyo,

which this week launched a global

e-waste initiative. “The recycling of

trace metals is essential to ongoing

production,” he says.

Fatal bushfires in Australia have had scientists calling for virtual reality systems that

would let people “experience” the conflagrations and react more rationally in the

face of their soaring flames and booming noise. Now the University of Nevada, Reno,

has developed such a system, called VRFire, which lets users wearing position trackers

and surrounded by video screens explore 3D bush terrain with realistic visuals and

the sound of spreading wildfires (http://tinyurl.com/36lumm).

A gadget that shrieks if a driver begins to doze at the wheel has been developed by

Revex of Japan. The firm’s $10 Drowse Prevention Alarm is built into a small earpiece

and contains a tilt sensor and an audio alarm. If the wearer’s head tilts forward

just 10 degrees, the sensor activates the alarm in case they are nodding off.

GIZMO

In US Department of Homeland Security field trials10 of the 14 robots tested experienced communication problems due to radio interference from other robots

ROBOT INTERFERENCEConflicting radio signals between robots could

hamper urban search and rescue operations

Journalist Noam Cohen on the anger amongst Wikipedia editors after the unmasking of “Essjay”, a trusted editor who had claimed to be a tenured

university lecturer in religion. In fact he is a 24-year-old ex-student with a close interest in Justin Timberlake’s musical career (The New York Times, 5 March)

“The wisdom of the crowd became the fury of the crowd”

CREA

TAS

SOUR

CE:

AFP

SOUR

CE: N

IST

Bone up withan ink-jet printer

TVs put squeeze on minor metals

www.newscientist.com 10 March 2007 | NewScientist | 25

–Safer braking ahead–

070310_N_Tech Opener.indd 25070310_N_Tech Opener.indd 25 5/3/07 5:57:31 pm5/3/07 5:57:31 pm