Possible new elementary particle described
BATAVIA, Ill., April 7 (UPI) -- U.S. particle physicists say they may have observed a new elementary particle or force of nature but admit it may be merely a statistical aberration.
Researchers at the Fermi National Accelerator Laboratory in Illinois said if the results are confirmed, they could require the first significant change in what is known as the standard model of physics in more than five decades, the Los Angeles Times reported Thursday.
"If this thing is real, it is a new type of very heavy particle that is not one of the ones theorists have been sitting around thinking about," physicist Michael Witherell of the University of California, Santa Barbara, told the Times.
"It would be very heavy, very interesting and very fundamental. It would turn over our understanding of particle physics."
However, the Fermilab researchers say there is about a 1-in-1,000 chance the results are due to a random statistical fluctuation, so they are not yet claiming a discovery.
"That's no more than what physicists tend to call an 'observation' or an 'indication,'" Caltech physicist Harvey Newman said.
For the finding to be considered real, further study would have to reduce the chances of a statistical fluke to about 1 in a million, scientists said.
"We will know this summer when we double the data sets and see if it is still there," Fermilab physicist Rob Roser, spokesman for the project, said.
Study: Health risk in long space missions
BIRMINGHAM, Ala., April 7 (UPI) -- Astronauts on deep space missions such as a trip to Mars might face health risks from radiation that could create heart problems, U.S. researchers say.
A study by scientists at the University of Alabama at Birmingham suggests exposure to cosmic radiation once outside the protection of Earth's magnetic field could be detrimental to astronauts' arteries, a university release reported Thursday.
The researchers analyzed the effect on mice of iron ion radiation commonly found in outer space to see if exposures promoted the development of atherosclerosis, as terrestrial sources of radiation are known to do, and found permanent damage in the aorta and carotid arteries.
"It's well known that prolonged exposure to radiation sources here on Earth, including those used in cancer treatment, excessive occupational exposure and atomic bombs, are associated with an increased risk for atherosclerosis," said Dennis Kucik, associate professor in the UAB department of pathology.
"But cosmic radiation is very different from X-rays and other radiation found on Earth. The radiation risks of deep-space travel are difficult to predict, largely because so few people have been exposed."
The only people who have been exposed to high levels of cosmic radiation are the 24 astronauts who have been to the moon as part of NASA's Apollo missions, Kucik said.
New measure of species threat developed
ADELAIDE, Australia, April 7 (UPI) -- Australian researchers say they've developed a new measurement of species threat to help conservationists better understand how close species are to extinction.
The index, developed by researchers from the University of Adelaide and James Cook University, is called Species Ability to Forestall Extinction, an Adelaide release reported Thursday.
The SAFE index is based on previous studies into the minimum population sizes needed by species to survive in the wild and measures how close species are to that minimum.
"The idea is fairly simple -- it's the distance a population is (in terms of abundance) from its minimum viable population size," Corey Bradshaw of the University of Adelaide's Environment Institute said.
SAFE is designed to complement the International Union for Conservation of Nature Red List of Threatened Species, not replace it, he said.
"Our index shows that not all Critically Endangered species are equal. A combined approach -- using the IUCN Red List threat categories together with the SAFE index -- is more informative than the IUCN categories alone, and provides a good method for gauging the relative 'safety' of a species from extinction," he said.
Of the 95 mammal species considered in developing the SAFE index, the researchers said, more than one in five are close to extinction and more than half are at "tipping points" that could take their populations to the point of no return.
Cities said most at risk in climate change
BOULDER, Colo., April 7 (UPI) -- Fast-growing urban areas worldwide, especially in developing countries, will suffer disproportionately from impacts of changing climate, a U.S. researcher says.
An examination of urban policies by Patricia Romero Lankao at the National Center for Atmospheric Research says cities worldwide are failing to take necessary steps to protect residents even though billions of urban dwellers are vulnerable to heat waves, sea level rise and other changes associated with warming temperatures, an NCAR release said Thursday.
"Climate change is a deeply local issue and poses profound threats to the growing cities of the world," Lankao says. "But too few cities are developing effective strategies to safeguard their residents."
Most cities are also failing to reduce emissions of carbon dioxide and other greenhouse gases that affect the atmosphere, she says.
Scientists say they are increasingly concerned about the potential impacts of climate change on cities, now home to more than half the world's population.
Their locations and dense construction patterns often place their populations at greater risk from natural disasters, they say, including those expected to worsen with climate change.
"What is at stake, of course, is the very existence of many human institutions, and the safety and well-being of masses of humans," Lankao says.
