Scientists at a small biotechnology company say they have used cloning to create human embryos from the skin cells of two men.
The work represents a step toward the promise of creating personalized embryonic stem cells that could be used for medical treatments. Although the embryos grew only to a very early stage, the work could also theoretically be seen as a step toward creating babies that are genetic copies of other people.
Scientists at the company, Stemagen, which is based in San Diego, California, said Thursday that they were the first to use human adult cells to create cloned embryos that advanced to the stage known as a blastocyst, from which embryonic stem cells typically are extracted.
Science & Technology
|
| ©NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington |
NASA's Messenger spacecraft made the first human visit to Mercury in 33 years when it flew by the planet on Monday. Mercury's last visitor from Earth, Mariner 10, was able to photograph about half of the planet's surface. Messenger was able to return images of about half of the never-before-seen surface of the planet.
Guess what they found in the new images? Craters. But they do show off new geological features and a history of the planet. The area at the top right of this image is called the Caloris basin, which was probably formed by an impact with an asteroid or comet. The brighter color shows that it may have a different composition of soil than the rest of the planet.
A deeper fundamental understanding of complex materials may now be possible, thanks to a pair of Princeton scientists who have uncovered a new insight into how crystals form.
The researchers' findings reveal a previously unknown mathematical relationship between the different arrangements that interacting particles can take while freezing. The discovery could give scientists insight into the essential behaviors of materials such as polymers, which are the basis of plastics.
Molecules in a material cooled to absolute zero can take on a multitude of different configurations. Historically, scientists' difficulty with identifying crystallized molecules' spatial arrangements from this high number of possible configurations has blocked theoretical efforts to understand these materials' qualities, but the new findings could offer the tool that science needs.
The researchers' findings reveal a previously unknown mathematical relationship between the different arrangements that interacting particles can take while freezing. The discovery could give scientists insight into the essential behaviors of materials such as polymers, which are the basis of plastics.
Molecules in a material cooled to absolute zero can take on a multitude of different configurations. Historically, scientists' difficulty with identifying crystallized molecules' spatial arrangements from this high number of possible configurations has blocked theoretical efforts to understand these materials' qualities, but the new findings could offer the tool that science needs.
Three-dimensional snowflakes can now be grown in a computer using a program developed by mathematicians at UC Davis and the University of Wisconsin-Madison.
No two snowflakes are truly alike, but they can be very similar to each other, said Janko Gravner, a mathematics professor at UC Davis. Why they are not more different from each other is a mystery, Gravner said. Being able to model the process might answer some of these questions.
No two snowflakes are truly alike, but they can be very similar to each other, said Janko Gravner, a mathematics professor at UC Davis. Why they are not more different from each other is a mystery, Gravner said. Being able to model the process might answer some of these questions.
|
| ©Janko Gravner and David Griffeath |
| Computer-generated snowflake |
An observatory which monitors the potential threat to earth from asteroids has launched a campaign to raise money to install a new telescope.
|
| ©BBC |
| The cost of installing the telescope is estimated at £54,000 |
New York - Scientists in California say they have produced embryos that are clones of two men, a potential step toward developing scientifically valuable stem cells. The new report documents embryos made with ordinary skin cells. But it's not the first time human cloned embryos have been made. In 2005, for example, scientists in Britain reported using embryonic stem cells to produce a cloned embryo. It matured enough to produce stem cells, but none were extracted.
|
| ©Unknown |
It was a warm, clear afternoon in the capital. The bustle of metropolitan commerce and tourism filled the streets. Small sailing vessels dotted the sheltered waters within sight of the government buildings, riding on a soft southerly breeze. The Sun sparkled on the gentle swells and wakes, lending a luminous glow to the poppies and tulips nodding in the parks along the water's edge. All was in order.
But suddenly, the sky brightened as if with a second, more brilliant Sun. A second set of shadows appeared; at first long and faint, they shortened and sharpened rapidly. A strange hissing, humming sound seemed to come from everywhere at once. Thousands craned their necks and looked upwards, searching the sky for the new Sun. Above them a tremendous white fireball blossomed, like the unfolding of a vast paper flower, but now blindingly bright. For several seconds the fierce fireball dominated the sky, shaming the Sun. The sky burned white-hot, then slowly faded through yellow and orange to a glowering copper-red. The awful hissing ceased. The onlookers, blinded by the flash, burned by its searing heat, covered their eyes and cringed in terror. Occupants of offices and apartments rushed to their windows, searching the sky for the source of the brilliant flare that had lit their rooms. A great blanket of turbulent, coppery cloud filled half the sky overhead. For a dozen heartbeats the city was awestruck, numbed and silent.
A one-ton "fossil rat" has been discovered in South America, scientists announced today.
The prehistoric, bull-size creature - the world's largest recorded rodent - has been identified from a well-preserved skull.
The prehistoric, bull-size creature - the world's largest recorded rodent - has been identified from a well-preserved skull.
|
| ©Unknown |
| An artist's reconstruction of Josephoartigasia monesi (top) is superimposed on an image of the prehistoric rodent's skull. A sculpture (below) further fleshes out the South American mammal. (See more pictures of the giant rodent - and its nearest living cousin.) |
Pasadena, Calif.- The potential of carbon nanotubes to diagnose and treat brain tumors is being explored through a partnership between NASA's Jet Propulsion Laboratory, Pasadena, Calif., and City of Hope, a leading cancer research and treatment center in Duarte, Calif.
Nanotechnology may help revolutionize medicine in the future with its promise to play a role in selective cancer therapy. City of Hope researchers hope to boost the brain's own immune response against tumors by delivering cancer-fighting agents via nanotubes. A nanotube is about 50,000 times narrower than a human hair, but it length can extend up to several centimeters.
Nanotechnology may help revolutionize medicine in the future with its promise to play a role in selective cancer therapy. City of Hope researchers hope to boost the brain's own immune response against tumors by delivering cancer-fighting agents via nanotubes. A nanotube is about 50,000 times narrower than a human hair, but it length can extend up to several centimeters.
Astronomers are using NASA's Hubble Space Telescope to dissect one of the largest structures in the universe as part of a quest to understand the violent lives of galaxies. Hubble is providing indirect evidence of unseen dark matter tugging on galaxies in the crowded, rough-and-tumble environment of a massive supercluster of hundreds of galaxies.
Dark matter is an invisible form of matter that accounts for most of the universe's mass. Hubble's Advanced Camera for Surveys has mapped the invisible dark matter scaffolding of the supercluster Abell 901/902, as well as the detailed structure of individual galaxies embedded in it.
Dark matter is an invisible form of matter that accounts for most of the universe's mass. Hubble's Advanced Camera for Surveys has mapped the invisible dark matter scaffolding of the supercluster Abell 901/902, as well as the detailed structure of individual galaxies embedded in it.
Comment: Continue to Part Five: Thirty Years of Cults and Comets