Posted by sciencewatch on 26 Mar 2006 10:11 pm. Filed under
General Science News.
Scientists uncover a skull that could be the missing link between Homo erectus and modern man.
Scientists in northeastern Ethiopia said Saturday that they have discovered the skull of a small human ancestor that could be a missing link between the extinct Homo erectus and modern man.
The hominid cranium — found in two pieces and believed to be between 500,000 and 250,000 years old — “comes from a very significant period and is very close to the appearance of the anatomically modern human,” said Sileshi Semaw, director of the Gona Paleoanthropological Research Project in Ethiopia.
(source: Associated Press story)
Posted by sciencewatch on 26 Mar 2006 7:43 pm. Filed under
General Science News.
Dispatch: What We’re Thinking About: What Is Life?
In their fourth exchange on the subject of artificial life, series host Robert Krulwich and contributing editor Jonah Lehrer consider the possibility that there may be more than one recipe for life.
Robert Krulwich, Jonah Lehrer
Posted by sciencewatch on 26 Mar 2006 6:16 pm. Filed under
General Science News.
2006 mathematics prize unveiled
Swedish mathematician Lennart Carleson wins the Abel Prize for outstanding work in mathematics.
Posted by sciencewatch on 25 Mar 2006 5:01 pm. Filed under
Nanotechnology.
Rice University (no pun intended) researchers report that they have created “nanorice” in a recent press release. The nanorice core is made of non-conducting iron oxide with an outer layer of gold. The research has been published in the journal Nano Letters. The nanorice is used to study plasmonic effects with particular application in surface-enhanced Raman scattering.
Research over the past decade has shown that nanoscale objects can amplify and focus light in ways scientists never imagined. The “how” of this involves plasmons, ripples of waves in the ocean of electrons that flow constantly across the surfaces of metals. When light of a specific frequency strikes a plasmon that oscillates at a compatible frequency, the energy from the light is converted into electrical energy that propagates, as plasmons, through the nanostructure.
Changing the shape of a metal at the nanoscale allows engineers and scientists to modify the properties of these plasmon waves, controlling the way that the metal nanostructure responds to light. Because of this, metal nanostructures can have beautiful, vivid colors that depend on their shape. Some nanoscale structures — like nanorice and nanoshells — act as superlenses that can amplify light waves and focus them to spot sizes far smaller than a wavelength of light.
In January 2005, for example, Halas and colleagues showed that nanoshells were about 10,000 times more effective at Surface-enhanced Raman Scattering (SERS) than traditional methods. Raman scattering is a type of spectrographic technique used by medical researchers, drug designers, chemists and others to determine the precise chemical makeup of materials.
Posted by sciencewatch on 25 Mar 2006 4:13 pm. Filed under
General Science News.
[NEWS] IMMUNOLOGY: Diabetes Studies Conflict on Power of Spleen Cells
Three separate attempts, reported on pages 1774, 1775, and 1778 of this issue of Science, have failed to replicate promising results reported 2 years ago, severely weakening the theory that the spleen cradles stem cells with curative powers against mouse diabetes. But some researchers haven’t given up on the idea. (Read more.)
Author: Jennifer Couzin