HANOVER, N.H., April 4 (UPI) -- While an asteroid is usually considered the culprit partially responsible for the extinction of dinosaurs, two U.S. researchers name a comet as chief suspect.
Jason Moore and Mukul Sharma of the Department of Earth Sciences at Dartmouth said they believe a high-velocity comet was the extraterrestrial source of the impact 65 million years ago that killed off almost all the dinosaurs and about 70 percent of all other species living on Earth.
That puts them at odds with most of the scientific community that considers an asteroid impact as the creator of the deeply buried and partially submerged, 110-mile-wide Chicxulub crater off of Mexico's Yucatan Peninsula.
They've based that belief on the levels of iridium and osmium, elements common in space rock such as asteroids, found in rock layers dating to the dinosaur extinction.
However, new evidence suggests lower iridium/osmium levels than previously believed at the layer of rock known as the K-Pg boundary, marking the end of the Cretaceous period, the epoch of the dinosaurs, and the beginning of the Paleogene period, with its notable absence of the large lizards.
Moore and Sharma said a comet explanation reconciles the conflicting evidence of a huge impact crater with the revised, lower iridium/osmium levels at the boundary.
"We are proposing a comet because that conclusion hits a 'sweet spot.' Comets have a lower percentage of iridium and osmium than asteroids, relative to their mass, yet a high-velocity comet would have sufficient energy to create a 110-mile-wide crater," Moore said.
"Comets travel much faster than asteroids, so they have more energy on impact, which in combination with their being partially ice means they are not contributing as much iridium or osmium."
Facebook reveals 'Home' for Android phones
MENLO PARK, Calif., April 4 (UPI) -- Facebook debuted its new Facebook Home interface for the Android operating system in California Thursday, calling it a "deeper" experience than an ordinary app.
Consisting of a set of the social network's apps that become the home screen of your Android phone, Home transforms it into "Cover Feed," a visually rich and swipe-able version of News Feed for a user's phone.
It also includes a updated version of messaging, complete with a feature Facebook has dubbed "Chat Heads," with colorful notifications that include a user's Facebook friends' pictures, CNET reported.
Facebook unveiled the software, which will be available for download to a limited number of Android phones starting April 12, at its Menlo Park headquarters.
"We're not building a phone and we're not building an operating system," Facebook head Mark Zuckerberg said. "We're building something a whole lot deeper than an ordinary app."
At the unveiling, Taiwanese phone maker HTC also announced plans for a model they've dubbed the HTC First, which will be the first smartphone to come with Facebook Home pre-installed.
It will represent a "great opportunity to bring mobile and social together," HTC chief Peter Chou said.
'Breathprints' could be diagnostic tool
ZURICH, Switzerland, April 4 (UPI) -- Exhaled breath carries chemical "breathprints" unique to each individual, a finding that may bring new medical diagnostic techniques, Swiss scientists say.
Researchers at ETH Zurich and at the University Hospital Zurich say modern high-resolution analytical methods that can provide real-time information on the chemical composition of exhaled breath could diagnose infectious and metabolic diseases, provide warnings of cancer and organ failure, and check dosage levels of medication.
They report they've developed an instrument-based version of a principle long known in traditional Chinese medicine, where doctors draw conclusions about the health state of a patient based on the smell of the exhaled breath.
The system will be able to detect specific compounds, which are present in breath at minute concentrations, for medical diagnosis, they said.
Although the potential usefulness of analyzing breath for medical diagnosis has been known, it is rarely practiced, researchers said.
"This might be due to the fact that existing methods for breath analysis are either rather slow, or are limited to a small number of compounds that they can detect," Pablo Martinez-Lozano Sinues, a senior scientist at ETH Zurich, said.
Compared to diagnostic analysis of blood or urine, a significant advantage of the breath technique is the exhaled "breathprint" is available within seconds after acquiring the sample, researchers said.
"Our goal is to develop breath analysis to the point where it becomes competitive with the established analysis of blood and urine," Malcolm Kohler, professor at the University Hospital Zurich, said.
New moms can view babies on iPad
LOS ANGELES, April 4 (UPI) -- A Los Angeles hospital says it is using iPads to let new mothers bond with their babies even when they are in separate areas of the facility.
Mothers who are not ambulatory after delivery, perhaps because of a Caesarean section or other complications, are able to see their newborns in the Cedars-Sinai Hospital's neonatal intensive care unit on iPads using a secured Internet connection, the hospital said in a release Thursday.
The program, called BabyTime, allows them to interact with their infants and the medical team caring for them.
"BabyTime will help bridge communication with the family and the baby's medical team and is an excellent use of technology to help new mothers bond with their babies, even when they cannot be physically at their babies' bedside," Charles F. Simmons Jr. of the Cedars-Sinai Department of Pediatrics said. "When doctors and nurses are treating a newborn in the NICU, mom can be right there asking questions and getting updates, even if she's on a different floor."
Twenty percent to 30 percent of mothers who undergo C-sections do not feel well enough to travel from their bed in the labor and delivery unit to the NICU for the first 24 to 48 hours, Simmons said.
When a baby is admitted to the NICU, an iPad is set up next to the infant's incubator, while a second iPad is delivered to the new mother, who can log onto BabyTime twice a day, hospital staff said.
"The BabyTime program will reduce fear and stress in the new moms as they are able to see their babies and also communicate with the doctors and nurses," NICU nurse manager Selma Braziel said.