Great white sharks: Awesome 1.8-ton bites
SYDNEY, Aug. 6 (UPI) -- Australian scientists say they've determined the bite force of a great white shark can reach about 1.8 tons, 20 times greater than a human's bite.
University of New South Wales researchers said, by comparison, a large African lion can produce only about 1,235 pounds of bite force.
Led by paleontologist and biomechanist Steve Wroe, the scientists used computer modeling to study the skull of an 8-foot-long male great white shark.
"Pound for pound the great whites' bite is not particularly impressive, but the sheer size of the animal means that in absolute terms it tops the scales," said Wroe.
But as powerful as great white sharks are, they pale when compared with the extinct great white shark Carcharodon megalodon -- which lived approximately 18 million years ago and might have grown to about 60 feet in length and weighed up to 100 tons -- arguably the most formidable carnivore to have ever existed on Earth, the researchers said.
Wroe and colleagues estimate the bite force of the megalodon at between 10.8 and 18.2 tons, at least 30 times that of the largest living great whites.
The research is to appear in the Journal of Zoology.
Dutch teacher discovers new space object
NEW HAVEN, Conn., Aug. 6 (UPI) -- A Dutch schoolteacher taking part in an online research project has discovered a gaseous object that astronomers say is of unknown origin.
Hanny van Arkel was one of more than 150,000 volunteer amateur astronomers who last year helped classify more than 1 million images on the Web site galaxyzoo.org. She reported she was unable to classify an irregular, green, glowing object.
Yale astrophysicist Kevin Schawinski and colleagues at Oxford University say van Arkel might have found a new class of astronomical object that's become known as Hanny's Voorwerp -- Dutch for "object."
Schawinski asked astronomers around the world to examine the Voorwerp with ground- and satellite-based telescopes. He and his colleagues say they believe the Voorwerp is illuminated by a quasar that was once active at the center of a nearby galaxy.
Schawinski explained that "light from that past still lights up the nearby Voorwerp, even though the quasar shut down sometime in the past 100,000 years." Scientists will soon use the Hubble Space Telescope to obtain a closer look.
A manuscript of the team's observations and analysis has been submitted for publication in the Monthly Notices of the Royal Astronomical Society.
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Pancreatic cancer gene therapy is created
RICHMOND, Va., Aug. 6 (UPI) -- U.S. cancer researchers say they have developed a chemoprevention gene therapy that successfully kills pancreatic cancer cells.
Scientists at Virginia Commonwealth University's Massey Cancer Center and Institute of Molecular Medicine discovered combining a dietary agent with a gene-delivered cytokine effectively eliminates human pancreatic cancer cells in mice.
Cytokines are a category of proteins that are secreted into the circulation and can affect cancer cells at distant sites in the body, including metastases, the researchers said. The cytokine used in the study was melanoma differentiation associated gene-7/interleukin-24, known as mda-7/IL-24. The dietary agent, perillyl alcohol, was combined with mda-7/IL-24, which is already used in other cancer treatments.
The results indicated the therapy not only prevented pancreatic cancer growth and progression, but it also effectively killed established tumors, thereby displaying profound chemopreventive and therapeutic activity.
"We are very excited at the prospect of (using) this chemoprevention gene therapy as a means of both preventing and treating pancreatic cancer, and it has significant potential to move rapidly into human clinical trials," said Professor Paul Fisher, who led the study.
The research is reported in the July issue of the journal Molecular Cancer Therapeutics.
New storm model better predicts flooding
STONY BROOK, N.Y., Aug. 6 (UPI) -- U.S. scientists say a newly developed storm surge model should provide more accurate predictions of flooding in the New York metropolitan area.
Professor Brian Colle and colleagues at Stony Brook University's School of Marine and Atmospheric Scienc developed the new modeling system from a state-of-the-art atmospheric model they coupled with an ocean model.
The researchers said they tested the model's ability to forecast peak water levels resulting from Tropical Storm Floyd in 1999 and a nor'easter in December 1992. They said the model predicted water levels that were within 10 percent of the observed levels.
"Ultimately, the goal is to provide emergency managers with a range of possibilities as to what may happen as the result of a storm, and this approach shows great promise," said Colle.
The researchers also used the new model to assess the potential impact of local tides and winds on the severity of flooding. Those results suggested New York City escaped significant flooding during Tropical Storm Floyd only because the storm's winds had weakened before reaching the region and because the strongest winds occurred during low tide.
The study appears in the Bulletin of the American Meteorological Society.
