Science & TechnologyS


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Ancient Mayans Were Nature Lovers, Not Destroyers


AndhaNews
Sat, 12 Dec 2009 06:00 UTC
In a new research, a team of archaeologists has disputed claims made by experts that the ancient Mayans agricultural practices led to their eventual collapse, and that the forest gardens cultivated by the Maya demonstrate their great appreciation for the environment.

Many archaeologists, anthropologists, and other scholars are of the opinion that the Mayan civilization's slash-and-burn approach to farming caused such widespread environmental devastation that the land simply could not sustain them.

But, research conducted by Anabel Ford, an archaeologist at UC Santa Barbara and director of the university's MesoAmerican Research Center, suggests the contrary may be true -- that the forest gardens cultivated by the Maya demonstrate their great appreciation for the environment.

A forest garden is an unplowed, tree-dominated plot that sustains biodiversity and animal habitat while producing plants for food, shelter, and medicine.
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Sherlock

Ancient Mediterranean Flood Mystery Solved?

Victoria Gill
BBC News
Wed, 09 Dec 2009 18:05 UTC
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© R. PibernatThe team made a reconstruction of the Mediterranean during the "megaflood."
Research has revealed details of the catastrophic Zanclean flood that refilled the Mediterranean Sea more than five million years ago.

The flood occurred when Atlantic waters found their way into the cut-off and desiccated Mediterranean basin.

The researchers say that a 200km channel across the Gibraltar strait was carved out by the floodwaters.

Their findings, published in Nature, show that the resulting flood could have filled the basin within two years.

The team was led by Daniel Garcia-Castellanos from the Research Council of Spain (CSIC).

He explained that he and his colleagues laid the foundations for this study by working on tectonic lakes.
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Studying Hair of Ancient Peruvians Answers Questions About Stress


ScienceDaily
Sat, 12 Dec 2009 00:00 UTC
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© iStockphoto/Amy HarrisView of the Lost Incan City of Machu Picchu near Cusco, Peru.
Recent studies show that one in three people suffer from stress and the number is on the rise. But stress isn't a new problem.

While the physiological state wasn't properly named until the 1930s, new research from The University of Western Ontario proves stress has plagued humans for hundreds, and perhaps thousands of years.

The first study of its kind, published in the Journal of Archaeological Science, detected the stress hormone cortisol in the hair of ancient Peruvians, who lived between 550 and 1532 A.D.

When an individual is stressed -- due to real or perceived threats -- cortisol is released into nearly every part of the body, including blood, saliva, urine and hair.
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Footprints

Ancient Amazon Civilization Laid Bare by Felled Forest

Linda Geddes
New Scientist
Thu, 10 Dec 2009 14:49 UTC
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© Edison CaetanoUncovering civilisation
Signs of what could be a previously unknown ancient civilization are emerging from beneath the felled trees of the Amazon. Some 260 giant avenues, ditches and enclosures have been spotted from the air in a region straddling Brazil's border with Bolivia.

The traditional view is that before the arrival of the Spanish and Portuguese in the 15th century there were no complex societies in the Amazon basin - in contrast to the Andes further west where the Incas built their cities. Now deforestation, increased air travel and satellite imagery are telling a different story.

"It's never-ending," says Denise Schaan of the Federal University of Pará in Belém, Brazil, who made many of the new discoveries from planes or by examining Google Earth images. "Every week we find new structures." Some of them are square or rectangular, while others form concentric circles or complex geometric figures such as hexagons and octagons connected by avenues or roads. The researchers describe them all as geoglyphs.
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Ladybug

Nuclear-Powered Transponder for Cyborg Insect

Sally Adee
IEEE Spectrum
Thu, 10 Dec 2009 22:29 UTC
This week at the International Electron Devices Meeting (IEDM), in Baltimore, Md., Cornell University engineers presented research that shows progress in powering cybernetic organisms with a radioactive fuel source.

Electrical engineering associate professor Amit Lal and graduate student Steven Tin presented a prototype microelectromechanical systems (MEMS) transmitter - an RF-emitting device powered by a radioactive source with a half-life of 12 years, meaning that it could operate autonomously for decades. The researchers think the new RFID transmitter, which produces a 5-milliwatt, 10-microsecond-long, 100-megahertz radio-frequency pulse, could lead to the widespread use of radioisotope power sources.

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Telescope

Dark Side of a Saturnian Moon: Iapetus is Coated with Foreign Dust


ScienceDaily
Fri, 11 Dec 2009 10:00 UTC
Iapetus is often called Saturn's most bizarre moon, due to its starkly contrasting hemispheres -- one black as coal, the other white as snow.

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© Cassini Imaging TeamCassini-Huygens spacecraft images of Iapetus' dark, leading side and its bright, trailing side. The high-resolution images shed new light on the long-standing puzzle of how Iapetus got its unusual coloration.
Images taken by the Cassini-Huygens spacecraft, orbiting Saturn since 2004, offer the most compelling evidence to date of why and how the moon got its yin-yang appearance, as well as clues to how other such satellites might have formed in the early universe. Analyzed by a research team that includes Cornell scientists, the images are detailed in the Dec. 10 online edition of the journal Science.

"This is not the most fundamental problem in the world," said research team member Joseph A. Burns, Cornell's Irving Porter Church Professor of Engineering and professor of astronomy. "But it's an enigma that's been puzzling astronomers for centuries."

Since pictures of Iapetus from the Voyager mission 30 years ago confirmed its intriguing color scheme, scientists have puzzled over whether Iapetus' dark-light contrast was the result of external debris hitting some of the moon, or whether the dark dust was the result of internal activity. Now they know the dust came from elsewhere.
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Book

Ancient Book of Mark Found Not So Ancient After All


ScienceDaily
Fri, 11 Dec 2009 10:00 UTC
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© University of ChicagoThe University of Chicago has found after careful study that what was previously was thought be a very old copy of the Gospel of Mark in its library is a modern fraud.
A biblical expert at the University of Chicago, Margaret M. Mitchell, together with experts in micro-chemical analysis and medieval bookmaking, has concluded that one of the University Library's most enigmatic possessions is a forgery. The book, a copy of the Gospel of Mark, will remain in the collection as a study document for scholars studying the authenticity of ancient books.

Scholars have argued for nearly 70 years over the provenance of what's called the Archaic Mark, a 44-page miniature book, known as a "codex," which contains the complete 16-chapter text of the Gospel of Mark in minuscule handwritten text. The manuscript, which also includes 16 colorful illustrations, has long been believed to be either an important witness to the early text of the gospel or a modern forgery, said Mitchell, Professor of New Testament and Early Christian Literature.

"The mystery is now solved from textual, chemical, and codicological (bookmaking) angles," said Mitchell, who first became intrigued by the codex when she saw it as a graduate student in 1982. Comprehensive analysis demonstrates that it is not a genuine Byzantine manuscript, but a counterfeit, she said, "made somewhere between 1874 and the first decades of the 20th century."
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Key

From Minnie to Mickey (and All They Did was Turn Off a Gene)

Steve Connor
The Independent
Fri, 11 Dec 2009 11:00 UTC
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© AlamyThe cells of the female ovary were transformed into cells normally found in male testes by turning off a gene during the development of the mouse embryo
Simple technique changes sex of a mouse - and reveals the gender war that rages in all of us.

The battle of the sexes is a never-ending war waged within ourselves as male and female elements of our own bodies continually fight each other for supremacy. This is the astonishing implication of a pioneering study showing that it is possible to flick a genetic switch that turns female ovary cells into male testicular tissue.

For decades, the battle of the sexes has been accepted by biologists as a real phenomenon with males and females competing against each other - when their interests do not coincide - for the continued survival of their genes in the next generation. Now scientists have been able to show that a gender war is constantly raging between the genes and cells of one individual.

One of the great dogmas of biology is that gender is fixed from birth, determined by the inheritance of certain genes on the X and Y sex chromosomes. But this simplistic idea has been exploded by the latest study, which demonstrated that fully-developed adult females can undergo a partial sex change following a genetic modification to a single gene.
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Bizarro Earth

Cosmic rays at 'space age' high, warns NASA


Press Trust, India
Fri, 11 Dec 2009 15:06 UTC
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Cosmic Rays
© PTIThe cosmic rays have the potential to harm astronauts, spacecraft.
osmic rays from outer space that can harm astronauts and spacecraft are increasing significantly and now at a "space age" high, NASA researchers have said.

The cosmic ray intensity in 2009 is at a "space age" high, said Richard Mewaldt, one of the scientists analysing data received from NASA's Advanced Composition Explorer spacecraft which is in solar orbit about a million miles from the earth.

"The intensity is actually about 20 per cent higher than solar-minimum periods of recent decades, and if this trend continues, NASA may want to reconsider how much shielding is required if astronauts return to the moon," said Mewaldt from California Institute of Technology.

Cosmic rays are very-high-energy particles that originate in explosions of massive stars elsewhere in the Milky Way galaxy. They travel at nearly the speed of light and strike the Earth from all directions.

People on Earth are not in danger from the rays since the planet is surrounded by a protective shield created by its atmosphere and magnetic field and activity on the sun, which creates a hard-to-penetrate bubble - called the heliosphere - of wind and magnetic field around the solar system.

However, there has been a lull in solar activity since around 2007 and research shows that when solar activity goes down then natural shielding is weakened and more cosmic rays reach Earth.
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Telescope

Scientists observe super-massive black holes using Keck Observatory in Hawaii

Gail Gallessich
University of California - Santa Barbara
Thu, 10 Dec 2009 20:52 UTC
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© M. Kishimoto, MPIfRUKIRT infrared images of the four target galaxies show them in near-infrared color, where the images at different infrared wavelengths are assigned to represent red, green and blue colors. Observations with the Keck Interferometer have resolved the inner structure of the bright nucleus in all the four galaxies. The inferred ring-like structure obtained for NGC 4151 at the top-left is depicted in the top-right panel. The ring radius is 0.13 light years, corresponding to an extremely small ~0.5 milli-arcsecond angular size on the sky. The distance to each galaxy is indicated in million light-years, together with the redshift (z) of each galaxy.
An international team of scientists has observed four super-massive black holes at the center of galaxies, which may provide new information on how these central black hole systems operate. Their findings are published in December's first issue of the journal Astronomy and Astrophysics.

These super-massive black holes at the center of galaxies are called active galactic nuclei. For the first time, the team observed a quasar with an active galactic nucleus, as part of the group of four, which is located more than a billion light years from Earth. The scientists used the two Keck telescopes on top of Mauna Kea in Hawaii. These are the largest optical/infrared telescopes in the world.

The team also used the United Kingdom Infrared Telescope (UKIRT) to follow up the Keck observations, to obtain current near-infrared images of the target galaxies.
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