Images Dated 22nd March 2006

Avian flu virus

Avian flu virus, computer artwork. A virus is a tiny pathogenic particle comprising genetic material enclosed in a protein coat. The coat contains surface proteins (spikes). Flu viruses have two types of surface protein, called haemagglutinin (H) and neuraminidase (N). These exist in several subtypes, only some of which are pathogenic in humans. The current bird flu that is endemic in birds is H5N1. The surface proteins are essential for the life cycle of the virus. Haemagglutinin allows the virus to bind to and enter a host cell, where the virus uses the cell's machinery to create more copies of the virus. Neuraminidase allows the new virus particles to exit the cell, so that they can infect others

© PASIEKA/SCIENCE PHOTO LIBRARY

Lake Pehoe, Torres del Paine National Park, Chile

Smooth colorful granite crags and glaciers of mountain range and its steep granite towers known as cuernos (horns) tower above emerald Lake Pehoe and beautiful forests of moss covered trees, fall morning; Torres del Paine National Park; Patagonia; Magellanes; Andes; Chile; South America

© 2006 John Eastcott and Yva Momatiuk registered at U.S. Library of Congress Office

86089470, Andes, Branch, Chile, Color Image, Day, Grass, Lake, Lake Pehoe, Landscape, Magellanes, Mountain, Mountain Range, National Park, Nature, No People, Outdoors, Patagonia, Patagonia Chile, Photography, Reflection, Scenics Nature, Torres Del Paine National Park, Tranquil Scene, Travel Destinations, Vertical

Generals Well

A view of the General's Well iron suspension footbridge connecting the Ness Islands in the River Ness, Inverness, Scotland, circa 1890. (Photo by London Stereoscopic Company/Hulton Archive/Getty Images)

© 2006 Getty Images

15802, Child, T Bris Inverness Invernesshire, Format, 57155533, Diry, Landscape, Black, Scenes, J126088007, Bridge, Childhood, Group, Male, Animal, Dog, White, Photograph, Europe, Britain, Scotland, Street