Space Bursts Provide Insight to Theory of Everything

 Light from some of the universe's most energetic explosions is allowing scientists to probe the nature of space-time, according to new observations of so-called gamma-ray bursts from the Japanese Aerospace Exploration Agency's Ikaros spacecraft. Photons released by these bursts help place limits on a unified model of all of the forces of nature — what scientists call a "theory of everything."

Using the Gamma-Ray Burst Polarimeter (GAP) onboard the spacecraft, a team of Japanese scientists have made the most precise measurements of energetic gamma-ray burst photons to date.

"This result puts a fundamental constraint on quantum gravity, a dream theory reconciling Einstein's theory of relativity and quantum theory," Kenji Toma, of Osaka University, said in a statement.

A quantum universe

Gamma-ray bursts are exceptioinally powerful explosions thought to result from violent events like star deaths and collisions of dense neutron stars. Toma and his team used detailed measurements of gamma-ray bursts to study the properties of the photons and determine their polarization, or how their electric fields are oriented in relation to the motion of the particles. The electric field of polarized light bounces up and down on an axis perpendicular to the direction the photons travel in. [5 Reasons We May Live in a Multiverse]

"Most 3D projection systems in movie theaters project two versions of the movie at two different polarizations — both at 45 degrees to the horizontal, but perpendicular to each other — so that when you view the movie through appropriately polarized glasses, the left eye sees the version of the movie meant for the left eye, and the right eye sees the version meant for the right," astrophysicist Derek Fox of the University of Pennsylvania told SPACE.com by email. Fox was not part of the team behind these findings, but studies gamma-ray bursts like those observed in this case.

The findings could have implications for superstring theory — the idea that all fundamental particles are actually loops of vibrating string — which is one attempt to unify nature's forces and create a theory of everything. If the idea is right, it would help reconcile two contradictory theories: Einstein's general relativity, which describes things that are very big, like gravity, and quantum mechanics, which describes the realm of the very small.

"We live in a quantum universe — quantum mechanics is needed to describe the behavior of all forces and all particles at the subatomic level," Fox said. "Ultimately, we can hope to develop a 'quantum gravity' theory of these phenomena."

Violating symmetry

Superstring theory scientists predict that if particles and anti-particles (antimatter is an opposite form of normal matter) traded places and time was reversed, the world would still look the same. If any evidence is uncovered that matter and antimatter actually act differently, or violate their apparent symmetry, it could offer support for superstring theory.

"If it were proven to be violated by any physical process, even at some tiny level, then this would radically change the direction of current theoretical approaches to constructing a unified model of all the forces of nature," Fox said.

Collecting observational evidence can prove challenging, as many quantum structures are too small to probe with present-day technology on Earth, making a space-based probe a necessity.

Photons streaming from gamma-ray bursts have thus far shown no changes in the rotation of their polarity. Such a rotation would indicate a lack of symmetry if time were reversed and particles and anti-particles switched.

Studying three gamma-ray bursts with significantly more precision than ever before, Toma and his team found no change in the polarization of the photons, implying that the symmetry is consistent to at least one part in 10 million. This is a new record in constraining the rules that govern nature, and will influence attempts to create a unified theory.

The research will be published in an upcoming issue of the journal Physical Review Letters.

A powerful source

Gamma-ray bursts are brief spikes that can last from a few seconds to a few minutes. The light from them can travel billions of light-years in the form of streaming high-energy photons that are unable to penetrate Earth's atmosphere.

Emitting as much energy in a few seconds as the sun does in a lifetime, the explosions may come from flare-ups during the formation of a neutron star or black hole — two possible outcomes of star deaths — or the sudden collision of neutron stars. The powerful forces involved in such events accelerate photons almost to the speed of light.

"Gamma-ray bursts have relatively high energies — compared to, say, radio or optical photons — which make them useful probes of the possible quantum structure of space-time," Fox said. He went on to call them "a natural choice as target sources for these tests."

Launched in May 2010, Ikaros is the first spacecraft outfitted with a solar sail. GAP is positioned at the probe's back end, pointing away from the sun and into deep space.

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Cancer Impacts Health of American Economy

 Cancer among American workers costs the businesses where they work billions of dollars a year in lost productivity, new research finds.

A study led by Grant Skrepnek of the University of Arizona Cancer Center in Tucson revealed that cancer in U.S. employees results in more than 33 million disability days per year, which amounts to $7.5 billion in lost productivity. Based on data from 2004 to 2008, the researchers estimate that 3.3 million American workers are diagnosed with cancer annually.

The study shows smaller businesses are most affected.  Of the workers with cancer that were analyzed, nearly 85 percent worked for companies with fewer than 500 employees. In addition, these small-business employees who had cancer were also more likely to be uninsured and had higher rates of other health problems, such as high blood pressure, depression and chronic obstructive pulmonary disease.

The research, one of the first to document the economic impact of cancer on the U.S. workforce, revealed that certain types of cancers, including women's cancers and melanoma, were associated with higher burdens of illness. For breast cancer, health care costs and hospitalizations were twice as high and disability days 55 percent higher than for other cancers.

The study's authors believe the true cost in terms of lost productivity is likely even higher than the disability days measured. Based on the results, they call for further efforts to reduce the burden of illness associated with cancer and its treatment.

The research was published in this month's edition of theJournal of Occupational and Environmental Medicine, the official publication of the American College of Occupational and Environmental Medicine.

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Stressed Out Entrepreneurs Are Still Happier than Other Workers

 Stress and worry may be a part of the job for entrepreneurs, but new research has found that entrepreneurs also say they have many other positive experiences at work.

In particular, entrepreneurs say they are more likely than other workers to report that they learned or did something new in the past day.  Entrepreneurs were also more likely than other workers to say they experienced enjoyment at work. 

"The same intellectual curiosity and energy needed to start and run a business may also drive entrepreneurs to seek out and take advantage of opportunities to learn or do something interesting or exciting on a regular basis," said Dan Witters, Sangeeta Agrawal and Alyssa Brown of Gallup, which conducted the research. "Entrepreneurs also have creative and strategic control of their business and manage their own schedule to execute on their business plan. Thus, they may have more flexibility to pursue interesting and exciting learning opportunities and activities than other workers."

Those benefits, however, did not stop entrepreneurs from experiencing some challenges as well. In particular, the researchers found that entrepreneurs experienced more worry and stress than other workers.

"One possible explanation for these differences may be that the personal and financial risks involved in starting and running a business may lead to additional worry and stress," the Gallup researchers said. "For example, entrepreneurs are significantly more likely than other workers to be uninsured and to struggle to afford necessary health care and medicine, which may cause them to have higher levels of stress and worry."

Despite that increased stress, entrepreneurs are still more optimistic than other workers. Thirty percent of entrepreneurs say they are optimistic about their futures while just 25 percent of workers share their sentiment.

"This elevated optimism, combined with communities that foster an entrepreneurial culture, may lead entrepreneurs to take business risks, create jobs, launch new products, and innovate," the researchers said.

The research was based on the responses of 273,175 interviews as a part of the Gallup-Healthways Well-Being Index.

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Bizarre Creature Found in 200-Million-Year-Old Cocoon

 About 200 million years ago, a leech released a slimy mucous cocoon  that unwittingly encased and trapped a bizarre animal with a springy tail, preserving it until researchers discovered the teardrop-shaped creature in Antarctica recently.

The cocoon looks like those produced by living leeches, such as the medicinal leech Hirudo medicinalis. Encased inside was a bell animal that looked similar to species in the genus Vorticella; its body extends 25 microns (about the width of some human hairs) with a tightly coiled stalk about twice that long. And like all eurkaryotes, the organism was equipped with a nucleus — in this case, a large horseshoe-shaped nucleus inside the main body. (A micron is one-millionth of a meter.)

This bell animal lived during the Late Triassic Period, when the Earth was much warmer, with dense rain forests flourishing along what is today the Transantarctic Mountain Range where it was found. At the time, Antarctica was part of the supercontinent Gondwana, though it was still located at high latitudes.

Past research has suggested this coiled stalk, which is used to attach to substrates, may be one of the fastest cellular engines known, changing from a telephone wirelike structure to a tight coil at a speed of about 8 centimeters (3.1 inches) per second — the equivalent of a human being walking the across more than three football fields in one second. [See Photos of the Bizarre Vorticella Creature]

Preserving soft tissue

Possibly even more amazing is the fact that this soft-bodied, microscopic creature survived the vagaries of time. Preserving a soft-bodied organism like this one for so long is tricky and requires some outside intervention to keep the tissues from degrading. In this case, rather than tree resin (called amber when hardened) that preserved dino DNA in the bellies of amber-trapped mosquitoes in "Jurassic Park," a mucous cocoon did the trick.

"This preservation is quite bizarre, but soft-bodied organisms cannot usually become fossilized unless they are rapidly entombed in a medium that prevents further decay," study researcher and paleobotanist Benjamin Bomfleur, of the Biodiversity Institute at the University of Kansas, told LiveScience.

Here's how the researchers think the hasty preservation took place: "A leech secreted a mucous cocoon that was deposited under water or in wet leaf litter, somewhere in a river system which lay in present-day Antarctica," Bomfleur said. This bell animal must have used its long, rapidly contracting stalk to attach itself to the cocoon soon after, becoming trapped and completely encased by the still-slimy cocoon, which hardened over hours to days.

"The cocoon with the such-enclosed bell animal then was deposited in mud that over time turned into the sedimentary layer where we found it some 200 million years later," Bomfleur explained.

The only other example of this type of preservation comes from a 125-million-year-old cocoon encasing a nematode worm and discovered in Svalbard.

Identifying the bizarre creature

When Bomfleur first noticed the tiny animal in samples he'd collected from Antarctica, he didn't know what he was looking at and didn't have time to consult with an expert in such microfossils, as he was working on his doctoral degree.

"Later this year, however, I finally found the time to look for someone with an expertise on freshwater microorganisms in order to get an expert opinion on the thing," Bomfleur said, adding he contacted Ojvind Moestrup of the University of Copenhagen.

Bomfleur recalled Moestrup looking at the fossil and saying, "It is often very hard or impossible to identify microfossils, but this one was easy. It is the ciliate Vorticella and the helical structure is the stalk."

Bomfleur and his colleagues detailed their research this week in the journal Proceedings of the National Academy of Sciences.

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Gene-altered mosquitoes could be used vs. dengue

KEY WEST, Fla. (AP) — Mosquito control officials in the Florida Keys  are waiting for the federal government to sign off on an experiment that would release hundreds of thousands of genetically modified mosquitoes to reduce the risk of dengue fever in the tourist town of Key West.

If approved by the Food and Drug Administration, it would be the first such experiment in the U.S. Some Key West residents worry, though, that not enough research has been done to determine the risks that releasing genetically modified mosquitoes might pose to the Keys' fragile ecosystem.

Officials are targeting the Aedes aegypti mosquitoes because they can spread dengue fever, a disease health officials thought had been eradicated in the U.S. until 93 cases originated in the Keys in 2009 and 2010.

The trial planned by mosquito control officials and the British company Oxitec would release non-biting male mosquitoes that have been genetically modified to pass along a birth defect that kill their progeny before reaching maturity. The idea is that they will mate with wild females and their children will die before reproducing. After a few generations, Key West's Aedes aegypti population would die off, reducing the dengue fever risk without using pesticides and at relatively a low cost, the proponents say. There is no vaccine for dengue fever.

"The science of it, I think, looks fine. It's straight from setting up experiments and collecting data," said Michael Doyle, pointing to research Oxitec has had published in peer-reviewed scientific journals. He inherited the project when he took the lead at the Florida Keys Mosquito Control District in mid-2011.

The district's website says the modified genes will disappear from the environment after the mosquitoes carrying it die, resulting in no permanent change to the wild mosquito population. The district also says that the mosquito species isn't native to the Keys, nor is it an integral food source for other animals.

Dengue fever is a viral disease that inflicts severe flu-like symptoms — the joint pain is so severe its nickname is "breakbone fever." It isn't fatal but victims are then susceptible at subsequent exposures to dengue hemorrhagic fever, which can be.

"It's very uncomfortable. You ache all over, you have a terrible fever," said Joel Biddle, a Key West resident whose dengue fever symptoms lasted more than a week in 2009.

Biddle is among those concerned about the Key West trial. He worries the modified genetic material will somehow be passed to humans or the ecosystem, and he wants more research done. He and other Key West residents also chafe at the fact that the project was in the works long before it was made public late last year.

Only female mosquitoes bite, so the modified genetic material wouldn't be passed on to humans, Mosquito control and Oxitec officials said. They also say they're being transparent about their data and the trial.

Real estate agent Mila de Mier has collected more than 117,700 signatures on a petition she posted on Change.org against the trial. Most come from outside the Keys, which de Mier says shows that tourists don't support the mosquito control district.

"We are dependent here on our tourists, and people from all over the country have been sending the message," de Mier said.

A University of Florida professor who studies mosquito control said Oxitec's technology works and evidence from the company's experiments elsewhere show it can control mosquito populations, but it's not clear whether its methods are as effective at controlling the risk of disease transmission. Phil Lounibos of the Florida Medical Entomology Laboratory also said it would take repeated releases of modified mosquitoes for the program to work, and the public outcry against genetically modified organisms, even when it's irrational, may be insurmountable.

"The public resistance and the need to reach some agreement between mosquito control and the public, I see that as a very significant issue, outside of the (operating) costs, since this is not just a one-time thing," Lounibos said.

The Aedes aegypti has shown resistance to pesticides used to control other species, and is the most difficult for the district to manage. Common in the Southeast and the Caribbean, it lurks in standing water around homes and businesses and can breed in containers as small as bottle caps.

District inspectors go door-to-door to remove the standing water where they breed, a time-consuming task. The district spends roughly $1 million a year to suppress Aedes aegypti, 10 to 15 percent of the agency's budget, Doyle said.

"Unfortunately, control of Aedes aegypti is a never-ending job," said Larry Hriber, the mosquito control district's research director.

In the trial, thousands of male mosquitoes bred by Oxitec would be released in a handful of Key West blocks where the Aedes aegypti is known to breed; the number of mosquitoes in those neighborhoods would be measured against the numbers from similar blocks where no modified mosquitoes were released.

The state's agriculture department oversees the mosquito control district, and Doyle said he would not expect any challenge from the state if the FDA signed off on the trial. The mosquito control district wouldn't need any local permit for the trial, either, but officials held a public meeting earlier this year and have posted information on the agency's website.

That trial may be years away. FDA spokeswoman Morgan Liscinsky said no genetically modified species can be released without approval.

There hasn't been a case of dengue fever in Key West since November 2010, but two other cases were reported elsewhere in South Florida this fall.

The mosquito trial proposed for Key West wouldn't be the first release of genetically modified insects in the U.S.

In 2009, the U.S. Department of Agriculture's Animal and Plant Health Inspection Service concluded that integrating genetically modified pink bollworms, bred by Oxitec to be sterile but more competitive in mating than regular bollworms, into the agency's plant pest control program was "the environmentally preferable alternative" to combat the cotton pest. The program was discontinued, however, after officials found that the genetically modified insects were not as hardy as pink bollworms sterilized through irradiation, and that their use in organic cotton fields would cause farmers to lose their certification.

Oxitec said the USDA's environmental assessment is one of several examples of proof that the trial's risks and methods are being independently evaluated. The company has trials in Brazil, the Cayman Islands and Malaysia, and it says it's gotten positive reviews from the latter two governments. It also cites its published research in peer-reviewed journals.

But Biddle, the onetime dengue patient, wants Oxitec to continue testing the modified mosquitoes outside the U.S.

"Why the rush here?" the Key West man said. "We already have test cases in the world where we can watch what is happening and make the best studies, because wouldn't it be wonderful if we could find out how it can be fail-safe — which it is not right now. It's an open Pandora's box."

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