CAPE CANAVERAL, Fla., Oct. 23 (UPI) -- Space shuttle Discovery lifted off Tuesday morning from the Kennedy Space Center on the U.S. space agency's 23rd mission to the International Space Station.

The 11:38 a.m. launch was on schedule under partly cloudy Florida skies and with no technical delays reported during the countdown. Ice formation on a liquid hydrogen hose had caused some concern, but inspectors determined it did not pose a launch hazard. The National Aeronautics and Space Administration said the STS-120 crew's 14-day mission will include five spacewalks -- four by the shuttle crew members and one by the space station's Expedition 16 crew.

The mission's main goals include adding an Italian-constructed U.S. module to the space station to act as a port for future laboratories. NASA said the installation of the Harmony module will mark the space station's first expansion since 2001.

Retired Air Force Col. Pamela Melroy is commanding the STS-120 mission, with astronaut George Zamka serving as the shuttle's pilot. The crew includes astronauts Daniel Tani, Douglas Wheelock, Scott Parazynski, Stephanie Wilson and Paolo Nespoli of the European Space Agency.

Zamka, Wheelock and Nespoli are making their first spaceflight.

Brain cancer vaccine testing begins

NEW YORK, Oct. 23 (UPI) -- U.S. medical scientists have started a clinical trial to evaluate a brain cancer vaccine that's used in addition to surgery and chemotherapy.

The New York University Medical Center study will focus on patients with glioblastoma multiforme, a deadly form of brain cancer.

The vaccine, called DCVax-Brain, incorporates proteins found in patients’ tumors and is designed to attack cancer cells containing those proteins.

"We are really excited about the promise of this vaccine," said Dr. Patrick Kelly, chairman of the center's Department of Neurosurgery. "Everything now depends on something in addition to surgery so that these tumors do not recur. A cancer vaccine like this may make a difference in extending life and maintaining a good quality of life."

Kelly and Dr. Michael Gruber will lead the research.

The trial will enroll patients 18 to 65 years old with newly diagnosed glioblastoma multiforme brain cancer who will receive standard primary treatment with surgery followed by radiation with concurrent chemotherapy. Enrolled patients will be randomized to receive the standard of care, and others will receive the standard of care and the vaccine.

The vaccine is manufactured by Northwest Biotherapeutics Inc. (OTCBB:NWBT) of Bothell, Wash.

Quantum laser nanoantenna demonstrated

CAMBRIDGE, Mass., Oct. 23 (UPI) -- U.S. engineers have created a quantum cascade laser nanoantenna for producing ultrahigh-resolution microscopes for chemical imaging in biology and medicine.

Harvard University researchers said their laser is capable of resolving the chemical composition of samples, such as the interior of a cell, with unprecedented detail.

The researchers -- who have filed for U.S. patents covering the new class of photonic devices -- said the laser’s design consists of two gold rods separated by a nanometer gap -- a device known as an optical antenna -- built on the facet of a quantum cascade laser. Such a laser emits invisible light in the region of the spectrum where most molecules leave their telltale absorption fingerprints.

The nanoantenna creates a light spot of nanometric size about 50 to 100 times smaller than the laser wavelength. That allows the spot to be scanned across a specimen to provide chemical images of the surface with superior spatial resolution.

The researchers -- led by graduate students Nanfang Yu, Ertugrul Cubukcu and physics Professor Federico Capasso -- report the findings in the journal Applied Physics Letters.

Study: Some viruses may cause obesity

RICHMOND, Va., Oct. 23 (UPI) -- A study suggests poor diet and lack of exercise might not entirely explain the prevalence of obesity in the United States -- viruses might also be at fault.

Dr. Richard Atkinson, the director of the Obetech Obesity Research Center in Richmond, Va., says there's a growing body of evidence demonstrating viruses might play a role in causing fat storage in humans.

"The cause of obesity is not a secret -- if you consume more calories than you burn in daily activity, you gain weight," said Atkinson. "What is interesting is that much of the obesity epidemic cannot be explained just by Americans eating more and exercising less. There are other factors at play, and viruses causing obesity may be one of them."

Atkinson reviewed multiple published articles that demonstrate a connection between viral infections and obesity. He found five animal viruses and three human viruses that have been shown to cause obesity in laboratory studies.

The researcher said he found significant evidence that animals, when infected with certain human viruses, experience excess weight gain and fat storage.

Atkinson reports his research in the October issue of the journal Mayo Clinic Proceedings.