At this stage the structure, though still just a featureless ball of cells, has started to differentiate into the body's three basic cell types (known as endoderm, mesoderm and ectoderm).

ECONOMIST: An embryonic development

But they perform together on a makeshift stage inside a brick structure with a roof made out of discarded U.N. bags.

NPR: Circus Brings Joy, Focus to Afghan Children

Some of the largest tech companies--Hewlett-Packard, Cisco, Dell--are at some stage of rethinking the structure and focus of their businesses in response to lackluster growth.

FORBES: Magazine Article

The IMF has won approval for the first stage of an overhaul of its voting structure that gives a slightly bigger voice to China and other emerging markets.

ECONOMIST: Turning grey

And since employment is spread across this time structure with relatively few working in final retail stage, savings and investment changes have dramatic impacts on employment.

FORBES: Think Consumption Is The 'Engine' Of Our Economy? Think Again.

It will also raise questions about the charging structure of online courses, which in this pioneering stage have mostly been free or low cost.

BBC: Online university giant gets bigger

The four-stage catalytic process transforms sugars derived from biomass into alkanes that have almost the exact chemical structure as traditionally produced biofuel.

CNN: Green breakthrough for 'biodiesel'