Science & TechnologyS


Beaker

Pesticide makes bees forget the scent for food, new study finds


Guardian
Mon, 01 Apr 2013 15:13 UTC
Bees and pesticides
© C.N.Connolly/PABees exposed to widely-used pesticides were slow to make or forgot completely the link between floral scents and food.

Neonicotinoids block part of brain bees use for learning, leaving them unable to make link between floral scents and nectar

Widely used pesticides have been found in new research to block a part of the brain that bees use for learning, rendering some of them unable to perform the essential task of associating scents with food. Bees exposed to two kinds of pesticide were slower to learn or completely forgot links between floral scents and nectar.

These effects could make it harder for bees to forage among flowers for food, thereby threatening their survival and reducing the pollination of crops and wild plants.

The findings add to existing research that neonicotinoid pesticides are contributing to the decline in bee populations.

It has also been revealed that a separate government field study on the impact of the pesticides on bees was seriously compromised by contamination because the chemicals are so widespread in the environment.
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Comet

Best of the Web: This is not an April Fools joke: Four asteroids flash past Earth in one day


Russia Today
Mon, 01 Apr 2013 16:33 UTC
Image
Earth is experiencing an unusual cosmic bombardment as four large asteroids pass it in just one day. Fortunately astronomers don't seem to joking when saying none are expected to pose danger.


Comment: Uhm, isn't that claim kind of meaningless after an asteroid/comet fragment totally blindsided everyone in Russia on February 15th?


The largest is 4034 Vishnu, which is 800 meters across - the length of the Burj Khalifa in Dubai - though much greater in mass. In comparison, the Tunguska meteorite that devastated hundreds of miles of Siberian wilderness when it landed in 1908 was estimated to be no bigger than 100 meters. The asteroid that may have led to the extinction of dinosaurs 65 million years ago may have been up to 10 kilometers across.

But 4034 Vishnu - which was discovered in 1986 - will pass nearly 23 million kilometers from the Earth's surface. The closest of the four, EN 89, will be just over 5 million kilometers away from the planet. The asteroid was only discovered a fortnight ago.

Comment: Wow, so now they're putting a price on civilization-destroying space rocks. What price human extinction?

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Info

Is an alien message embedded in our genetic code?

Ray Villard
Discovery News
Mon, 01 Apr 2013 10:27 UTC
Genetic Code
© NASA, DOE
The answer to whether or not we are alone in the universe could be right under our nose, or, more literally, inside every cell in our body.

Could our genes have an intelligently designed "manufacturer's stamp" inside them, written eons ago elsewhere in our galaxy? Such a "designer label" would be an indelible stamp of a master extraterrestrial civilization that preceded us by many millions or billions of years. As their ultimate legacy, they recast the Milky Way in their own biological image.

Vladimir I. shCherbak of al-Farabi Kazakh National University of Kazakhstan, and Maxim A. Makukov of the Fesenkov Astrophysical Institute, hypothesize that an intelligent signal embedded in our genetic code would be a mathematical and semantic message that cannot be accounted for by Darwinian evolution. They call it "biological SETI." What's more, they argue that the scheme has much greater longevity and chance of detecting E.T. than a transient extraterrestrial radio transmission.

Writing in the journal Icarus, they assert: "Once fixed, the code might stay unchanged over cosmological timescales; in fact, it is the most durable construct known. Therefore it represents an exceptionally reliable storage for an intelligent signature. Once the genome is appropriately rewritten the new code with a signature will stay frozen in the cell and its progeny, which might then be delivered through space and time."

To pass the designer label test, any patterns in the genetic code must be highly statistically significant and possess intelligent-like features that are inconsistent with any natural know process, say the authors.
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Fireball 4

Mercury meteorite? Green space rock found in Morocco may be first from innermost planet

Miriam Kramer
Huffington Post
Sun, 31 Mar 2013 10:46 UTC
Image
This green meteorite that landed in Morocco in 2012 could be from Mercury.
Scientists may have discovered the first meteorite from Mercury.

The green rock found in Morocco last year may be the first known visitor from the solar system's innermost planet, according to meteorite scientist Anthony Irving, who unveiled the new findings this month at the 44th annual Lunar and Planetary Science Conference in The Woodlands, Texas. The study suggests that a space rock called NWA 7325 came from Mercury, and not an asteroid or Mars.

NWA 7325 is actually a group of 35 meteorite samples discovered in 2012 in Morocco. They are ancient, with Irving and his team dating the rocks to an age of about 4.56 billion years.

"It might be a sample from Mercury, or it might be a sample from a body smaller than Mercury but [which] is like Mercury," Irving said during his talk. A large impact could have shot NWA 7325 out from Mercury to Earth, he added.

Irving is an Earth and Space Sciences professor at the University of Washington and has been studying meteorites for years. But the NWA 7325 meteorite is unlike anything found on Earth before, he told SPACE.com.
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Info

Asteroid found orbiting Uranus

Jacob Aron
NewScientist
Thu, 28 Mar 2013 22:36 UTC
Uranus
© Roger Harris/SPLUranus is not as lonely as we thought.
Object: A 60-kilometre-wide asteroid

Location: 3 billion kilometres ahead of Uranus, in the planet's L4 Lagrange point

Uranus has a forbidden friend. The first asteroid to share the planet's orbit has been found, despite claims that Jupiter's mighty gravity should steal such companions away.

The finding hints that more of these asteroids, called Trojans, lurk around unexpected worlds. Since Trojans don't always stay in place, finding new ones improves our picture of how space rocks migrate around the solar system. It also means there may be super-sized Trojans sharing orbits with massive exoplanets.

Mike Alexandersen of the University of British Columbia in Vancouver and colleagues discovered the 60-kilometre-wide Trojan, named 2011 QF99, from an observatory in Hawaii. It lives in a Lagrange point, where the gravitational tugs from the sun and Uranus balance out.

There are five possible Lagrange points around two massive bodies, such as the sun and a planet. The ones called L4 and L5 sit ahead of and behind the planet, respectively, in its orbital path. These points have long been known to act as dust-gathering niches. Jupiter's L4 and L5 points host more than 3000 asteroids of various sizes. They are the original cosmic Trojans, named after the legendary fighters of ancient Troy.
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Laptop

Digital evolution: DNA may bring computers to life

Tanya Lewis
LiveScience
Thu, 28 Mar 2013 15:52 UTC
Biological Computer
© Covert LabScientists have developed the biological equivalent of a transistor.
The transistor revolutionized electronics and computing. Now, researchers have made a biological transistor from DNA that could be used to create living computers.

A transistor is a device that controls the flow of electrons in an electrical circuit, which acts as an on-off switch. Similarly, the biological transistor - termed a transcriptor - controls the flow of an enzyme as it moves along a strand of DNA (deoxyribonucleic acid). These cellular building blocks could be used to do anything from monitoring their environment to turning processes on and off in the cells. The findings were reported today (March 28) in the journal Science.

"Transcriptors are the key component behind amplifying genetic logic," lead author Jerome Bonnet, a bioengineer at Stanford University, said in a statement. On their own, these devices do not represent a computer, but they allow for logical operations, such as "if this-then that" commands, one of three basic functions of computers (the other two being storing and transmitting information).

To make the transcriptors, the researchers took a group of natural proteins, the workhorses of cells, and used them to control how the enzyme known as RNA polymerase zipped along a DNA molecule. The team used these transcriptors to create the mathematical operators that perform computations using Boolean logic.
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Info

'Fairy Circle' mystery solved?

Rachel Nuwer
ScienceNow
Thu, 28 Mar 2013 13:35 UTC
Fairy Circles
© Norbert JuergensCaught! Fairy circles freckle the landscape in NamibRand, Namibia. Are sand termites (inset) to blame?
Like others who came before him, Norbert Juergens was caught in the spell of fairy circles. These bare patches of ground, often outlined with a fringe of tall grass, pockmark a 2000-kilometer-long strip of desert stretching from Angola to South Africa. Though the formations have confounded scientists for years, Juergens - an ecologist at the University of Hamburg in Germany - thinks that he may be the first to crack the puzzle.

The strange saga of the fairy circles got even stranger last year. That's when Walter Tschinkel, a biologist at Florida State University in Tallahassee, analyzed 4 years of satellite images of the formations in Namibia's NamibRand Nature Reserve. Tschinkel had been intrigued by the circles since first encountering them on a vacation to Africa in 2005. The images revealed that some of the formations arose and others vanished over the 4-year period - the first evidence that they were somehow "alive." Extrapolating from the data, Tschinkel estimated an average "lifespan" of 41 years. But he couldn't figure out what made them. Some suspected that termites were killing the grass from below, but Tschinkel found no evidence that the insects caused fairy circles. Nor did he find anything wrong with the soil itself.

Juergens's search for answers began a year after Tschinkel's. He started traveling throughout Africa in 2006 - including to remote areas in Angola, still reeling from its recent civil war - in search of fairy circles. He became intrigued with the formations after noticing, like Tschinkel, that the mysterious patches seemed to come and go from the landscape. He recorded any signs of animal life that he came across in and around the circles, such as tracks, dung, or nests. He also dug trenches from the center of the circles to the outside in order to find any subterranean organisms that may be lurking below.
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Info

Deadly blood type explains medical mystery

Charles Choi
LiveScience
Thu, 28 Mar 2013 07:10 UTC
Vel Blood Type
© Nicolle Rager Fuller, National Science FoundationPeople with the rare Vel-negative blood type can die if they receive a Vel-positive transfusion, and now scientists know why.
A blood type that can turn blood transfusions deadly has proven a perplexing mystery for 60 years. Now researchers have finally identified the secret behind the blood type known as "Vel," findings that could help make blood safer for hundreds of thousands of people worldwide.

The mystery began in 1952, when a 66-year-old woman in New York, sick with colon cancer, received a blood transfusion and unexpectedly suffered from a severe and potentially fatal rejection of the blood. Investigators referred to her, using her last name, simply as Patient Vel.

Further research found that Mrs. Vel had developed a potent immune response against some unknown compound found on the red blood cells she had received. However, scientists could not identify this compound, opening the mystery of a new blood type, "Vel-negative."

"The molecular basis of the Vel-negative blood type remained elusive for more than 60 years despite intense efforts worldwide," researcher Bryan Ballif, a biochemist and mass spectrometrist at the University of Vermont, told LiveScience.
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Cassiopaea

A new class of supernova

Sid Perkins
ScienceNow
Tue, 26 Mar 2013 13:00 UTC
Supernova
© Christine Pulliam/CfA
Some of the most powerful explosions in the universe just got a bit more varied. Astronomers have already categorized two broad groups of supernovae: type Ia supernovae presumed to result from the complete disruption of a white dwarf star, and the type II, Ib, and Ic supernovae thought to explode when the core of giant star collapses. Now, they say that a type of exploding star first thought to be an unusual sort of type Ia supernova is actually a different class of supernova altogether.

Explosions of these stars, dubbed type Iax, release somewhere between 1% and 50% the energy of a type Ia supernova, and there are hints that in many cases a remnant of the star may survive the initial outburst. Like type Ia supernovae (but unlike the smaller, garden-variety exploding stars called novae), spectra of type Iax stars don't include any signs of hydrogen.

Most of the 25 stars share more than 25 different characteristics - a sign that the stars probably not only look alike but are physically similar, the researchers report online and in a forthcoming issue of The Astrophysical Journal. Type Iax supernovae most likely form in binary star systems when a superdense, carbon- and oxygen-rich white dwarf star (center of disk at left) robs material from its helium-rich partner, eventually accumulating enough mass on its surface to trigger an explosion.

Astronomers likely have discovered so few type Iax supernovae only because they are faint, not because they are rare: The team estimates that for every 100 type Ia supernovae explosions that occur, there are about 31 type Iax supernovae.
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Info

Rethinking the cosmic speed limit

John P. Millis, Ph.D.
RedOrbit
Tue, 26 Mar 2013 13:31 UTC
Speed of Light
© R.T. Wohlstadter/Shutterstock
When we talk about the vacuum of space, we imagine a complete lack of matter - a cold void, dark, and absent of all energy. Over the last century, however, physicists have come to realize that the emptiness of space is anything by empty.

On the macro scale, the vacuum of empty space may appear to lack matter and energy as we normally think of it. But when we look closely, and begin to examine the quantum interactions that take place in the very fabric of space-time that binds our Universe together, we find a busy network of particles and light popping in and out of existence.

These so-called virtual particles are just like any other particles of their type, but they are almost immediately re-absorbed by the vacuum, making their detection difficult. Understanding these particles, their energies and how they interact with the vacuum of space-time is crucial to fully understanding the physical laws of nature.

And now, two independent research teams have found that the properties of the vacuum, and how these virtual particles behave, may reveal some exciting implications about relativity and particle physics theory.
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