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Microvascular Surgery for Stroke

An operation to increase cerebral blood flow by joining an artery in the scalp to one on the surface of the brain is made possible by new technology: an operating microscope and microinstruments

By Jack M. Fein

The Tracks of Moving Cells

Migrating tissue cells will remove particles of gold from a particle-coated substrate, creating a graphic record of their movements that reveals a surprising degree of order

By Guenter Albrecht-Buehler

The Food-sharing Behavior of Protohuman Hominids

Excavations at two-million-year-old sites in East Africa offer new insights into human evolutionary progress by showing that early erect-standing hominids made tools and carried food to a home base

By Glynn Isaac

The Birth of Massive Stars

The birth of stars many times hotter and more massive than the sun may be triggered by shock waves traveling through large cool clouds of interstellar gas and dust

By Michael Zeilik

Kimberlite Pipes

These remarkable fossil volcanoes rise from a great depth. They are the ultimate source of diamonds and also of rocks that may be specimens of materials from the earth's mantle

By Keith G. Cox

Insects of the Water Surface

The attractive force between water molecules creates an elastic film at the surface of a calm body of water. All over the world the same four types of insects are found on or near this unusual environment

By Lorus J. Milne and Margery Milne

Atmospheric Halos

Rings around the sun and moon and related apparitions in the sky are caused by myriad crystals of ice. Precisely how they are formed is still a challenge to modern physics

By David K. Lynch


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