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Engineering the future: The 2013 Dyson award shortlist

A look at the 20 inventions battling it out for the 2013 James Dyson prize. The shortlisted selection will now be compared for the quality and innovation of their designs.
This clever device is called Xarius and is from German. It uses the wind to make energy which can then be used to recharge other gadgets like phones.
Xarius
Twenty inventions are shortlisted for this year's James Dyson Award for engineering. The winner will receive £30,000 in November. This entry is a company called Biowool. It takes waste material from the wool industry and turns it into a material that can be used instead of plastic.
Biowool
The Revolights product aims to protect bike riders by adding lights to the wheels' rims. The US invention is makes cyclists more easily seen by drivers.
Revolights
Comb is a design for a driverless dumper truck. The Austrian project proposes using GPS location tech to direct the vehicle, meaning it would not need a driver.
Comb – Muldenkipper
This Stack slim-line printer designed in Switzerland moves down a pile of paper as it goes, rather than requiring the sheets to be loaded inside.
Stack
This British design by TeamO is designed to make sure that someone being towed in a lifejacket is put in a position where their face is out of the water. Its also got an inbuilt neck support to help protect the wearer from waves.
TeamO
The Cortex is a 3D-printed cast, it aims to replace plaster-based casts which are heavy, itchy and smelly to use. Its New Zealand creators highlight that it is made out of recyclable plastic to reduce waste.
Cortex
The Renewable Wave Power generator has already won the prize in the UK round of James Dyson's competition. It uses pistons to get power from tidal waters.
Renewable Wave Power
The Canadian team behind this machine have designed it to automatically stitch together cuts made during surgery instead of a doctor doing it. The team says it could help operations be completed more quickly.
Robotic surgery
Mamori is a gum shield fitted with sensors, designed by an Irish team of engineers. It is intended to monitor sportsmen and sportswomen, contacting medical staff it it detects a high risk of concussion.
Mamori
Oltu is a Spanish invention which uses the extra heat produced behind a fridge to power four different areas to store fruit and veg. The storage units can be set to be cold or warm, wet or dry.
Oltu
The US-designed Titan Arm is an upper-body exoskeleton that promises to boost the wearer's strength. Its creators suggest it can also be used to help injured people rebuild muscle.
Titan Arm
E-health uses Raspberry Pi and Arduino computers to offer a cheap way of measuring blood pressure, blood oxygen levels and other data. Its Spanish inventors suggest the information could then be used by owners to make a medical diagnosis without leaving the home.
E-health
The Awaring is designed to help people with a hearing problems follow conversations. The Japanese device uses lights to indicate which person is speaking and how loud they are.
Awaring
Handie's parts can be made using a 3D printer. Its Japanese makers suggest that should make it cheaper to maintain the prosthetic hand.
Handie
Gluco uses a smartphone linked to a special watch to measure blood sugar levels. The French team behind it say that if levels become too high or low the information could be sent to someone who could help.
Gluco
Australian invention Roam is a oxygen cylinder created for young children. It comes with a nose mask and, its creators say, is easier to carry than current masks used to treat severe asthma attacks.
Roam
Lenify is a stretcher that splits into three parts. The US team behind it says their design allows medics to slide the different sections under the patient rather than having to lift and place the injured person onto a canvas, which can cause further harm. The winner will be announced on 7 November.
Lenify
Hydros offers an update to the way life jackets are made. The Irish team behind it says it is more comfortable to wear and offers better protection against the cold than traditional designs.
Hydros
Sono, from Austria, aims to cancel out certain sounds, stopping them pass through a window. Users can select which tones to block out via wi-fi.
Sono