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UCSD Experts Calculate How Much Information Americans Consume
Posted by wideant in Social Sciences on March 5, 2010
U.S. households consumed approximately 3.6 zettabytes of information in 2008, according to the “How Much Information? 2009 Report on American Consumers,” released today by the University of California, San Diego. One zettabyte is 1,000,000,000 trillion bytes, and total bytes consumed last year were the equivalent of the information in thick paperback novels stacked seven feet high over the entire United States, including Alaska.
The How Much Information? project is creating a census of the world’s information in 2008. The study measured information consumed by U.S. consumers in and outside the home for non-work related reasons, and included the gamut of information sources, including going to the movies, listening to the radio, talking on the cell phone, playing video games, surfing the Internet, and reading the newspaper, among other things. Read the rest of this entry »
Children with headache
Family quarrels and a lack of free time can promote headaches in children. This is what Jennifer Gassmann and her coauthors concluded in their study on risk factors, which appears in the current issue of the Deutsches Ärzteblatt International.
This investigation was a component of a large-scale study entitled “Children, Adolescents, and Headache” (Kinder, Jugendliche und Kopfschmerz—KiJuKo), in which data were collected in four annual “waves” from 2003 to 2006. Out of a multitude of variables tested in the larger study, the authors chose to look at the ones that concerned the children’s family and leisure time. Up to 30% of all children around the world complain of headache symptoms arising at least once per week.
Boys who experienced more than one family quarrel per week had a 1.8 times higher risk of developing headaches. The amount of free time available to them seemed to be even more important: boys who only sometimes had time to themselves had a 2.1 times higher risk of developing headaches. Read the rest of this entry »
Tropical birds waited for land crossing between North and South America: study
Posted by wideant in Plants & Animals on March 4, 2010
Despite their ability to fly, tropical birds waited until the formation of the land bridge between North and South America to move northward, according to a University of British Columbia study published this week in the Proceedings of the National Academy of Sciences Early Edition.
“While many North American birds simply flew across the marine barriers that once separated the continents, tropical birds, especially those in Amazon forest regions, began colonization of North America almost entirely after the completion of the land bridge,” says lead author Jason Weir, who conducted the study as part of his PhD at UBC.
“This study is the most extensive evidence to date that shows the land bridge playing a key role in the interchange of bird species between North and South America and the abundant biodiversity in the tropical regions,” says Weir, now a post-doctoral fellow at the University of Chicago. Read the rest of this entry »