For both modes of crystal fibre, the pattern of holes is generated by stacking hollow glass tubes a millimetre or so in diameter to form a rod several centimetres thick.

ECONOMIST: A new approach to making optical fibres

The hollow body, made of mulberry wood, is shaped in the form of a figure eight and is held horizontally, while the eleven metal strings are plucked with a plectrum.

UNESCO: MEDIA SERVICES

While Woods ended a 30-month wait for a PGA Tour title at the Arnold Palmer Invitational in March, he then struggled to maintain that form as he finished 40th at the Masters, missed the cut at Quail Hollow and then tied for 40th at the Players Championship.

CNN: STORY HIGHLIGHTS

An alternative is Inertial confinement fusion (ICF), in which fusion of nuclei is initiated by heating and compressing a fuel target, typically in the form of a pellet containing deuterium and tritium contained in a device called a hohlraum (hollow space or cavity) using an extremely powerful laser.

FORBES: U.K. And U.S. Join Forces on Laser-Fusion Energy