Search for 'Mona Lisa' unearths tombs
FLORENCE, Italy, May 12 (UPI) -- A search for the remains of the woman believed to have sat for Leonardo da Vinci's "Mona Lisa" unearthed two tombs under an Italian convent, officials said.
Historians think Lisa Gherardini Del Giocondo, who died in Florence in 1542, modeled for Leonardo's celebrated portrait, now hanging in the Louvre in Paris, ANSA reported.
In a project overseen by Tuscany's Archaeological Ministry, diggers are working in the church of the former convent of St. Ursula using light, low-impact tools such as shovels, trowels, rakes, brushes and sometimes just hands, the Italian news agency said.
Archaeologists were led to the site by references in historical documents and by georadar scans.
"The finding is consistent with our records," art historian Silvano Vinceti, a spokesman for the dig, said. "We should be where the altar once stood, and where a trapdoor led to the crypt we saw on the georadar scan."
The goal of the dig is to find Del Giocondo's remains and compare her DNA with that of two of her children buried in Florence's Santissima Annunziata church. Then, they will reconstruct her face from the skull and compare it to Leonardo's painting.
Del Giocondo became a nun after her husband's death and died in the convent on July 15, 1542, at age 63.
Sugar enlisted to fight bacteria
BOSTON, May 12 (UPI) -- U.S. researchers battling bacteria that resist medications by becoming zombie-like then reawakening to cause new infections say they have a new weapon -- sugar.
Boston University bioengineer James Collins and his colleagues have discovered how to make these "persisters," thought to underlie many stubborn infections, susceptible to drugs by the deliciously simple act of adding sugar, The Boston Globe reported Wednesday.
"Could we wake these guys up?" Collins asked. "Could we ... get them up off the ground so we can punch them and knock them out?"
In laboratory tests, the researchers said, the sugar energized the bacteria sufficiently so that a particular type of antibiotic could make its way into the cells and destroy them.
Persisters are believed to be involved in hard-to-treat infections such as tuberculosis and biofilm infections that grow on implanted medical devices.
"Persisters are very difficult to eradicate; they evolved to survive," said Kim Lewis, director of the Antimicrobial Discovery Center at Northeastern University. "Looking for ways to try to beat them is very important."
Sperm whale 'accents' studied
HALIFAX, Nova Scotia, May 12 (UPI) -- Sperm whales communicate with clicking sounds and can tell which whale is "speaking" by the sound qualities of the clicks, Canadian researchers say.
Researchers at Dalhousie University say the clicking patterns are known as "codas," with different codas meaning different things. Caribbean and Pacific whales have different repertoires of codas, much like regional dialects, the researches said a university release issued Thursday.
Just as we can tell our friends apart by the sounds of their voices and the way they pronounce their words, sperm whales can identify each other by the different "accents" of the clicks, the researchers said.
The findings were recently published in the journal Animal Behavior.
Understanding how whales communicate is important to understanding threats that human activities present to the whale, the researchers said.
Increased shipping traffic, underwater explosions caused by the search for oil and military sonar all contribute to ocean noise that masks communication between whales.
"No one wants to live in a rock concert," marine biologist Shane Gero said.
Noise pollution is especially troublesome in the ocean because "it is a totally different sensory world," he said.
Sperm whales can dive to depths of greater than 3,200 feet and depend on sound for communication and navigation in the pitch black of the deep water.
Cellphone effects on body studied
BERNE, Switzerland, May 12 (UPI) -- Cellphone radiation can affect biological processes but there's no evidence linking everyday exposure to health problems, Swiss researchers say.
The question of whether cellphones are bad for human health and the environment has long been debated, and a Swiss research program examined the issue, Swissinfo.ch reported Wednesday.
"The concern of the population is quite substantial concerning non-ionizing radiation so it was thought a good idea to launch a research program," Alexander Borbely, who headed the study, said.
However, there were "no easy answers to these simple questions," the four-year program from the Swiss National Science Foundation concluded.
The Swiss Federal Environment Office said the radiation issue was complex.
"Those who had hoped that the [study] would provide the final word on the harmfulness or not of this radiation will be disappointed because the program couldn't give a definitive answer," a statement issued by the office said.
The office said there were still potential risks, and the country already has strict non-ionizing radiation limits in place.
Borbely said follow-up studies are needed to see how the effects detailed in the research program affect the body over the long term.
"These are subtle effects but nevertheless they are there and they have been confirmed, and so people would like to know more about how these come about and whether they have any potential health implications," he said.
