Sunday, April 28, 2013

Mexican newspaper photographer found dead, mutilated

MEXICO CITY (AP) -- The hacked-up bodies of a photojournalist and another young man have been found in the northern Mexico city of Saltillo, authorities said Thursday.

Photographer Daniel Martinez Bazaldua, 22, had recently been hired to cover social events for Vanguardia, the paper said in a story in its online edition. Officials identified the other man as Julian Zamora, 23.

Saltillo is in northern Coahuila state, an area where the Zetas drug cartel is active. Another Coahuila newspaper recently announced it would no longer publish stories about drug gangs, after receiving threats apparently signed by a Zetas leader.

State prosecutors said the bodies were found Wednesday in a jumbled pile of severed parts on a street, next to a hand-lettered message that appeared to indicate the Zetas were responsible for the killings.

The state government said the sign suggested the two young men had deserted from a drug gang.

Coahuila state Attorney General Homero Ramos told reporters later that investigators had testimony indicating both men "were participating in illegal activities."

Vanguardia criticized that accusation, noting that the message left at the scene also contained threats to police.

"We think it is sad and alarming that Coahuila has become a state in which the authorities condemn murdered people, converting them into criminals, without offering the least evidence," the newspaper wrote.

"Only a serious, professional investigation can find out the truth that society deserves," Vanguardia said.

Vanguardia Editorial Director Ricardo Mendoza told The Associated Press that Martinez Bazaldua was "very calm," ''friendly" and "enthusiastic," and said he did not know whether the killing was related to his work as a photographer.

In some cartel-plagued cities in Mexico, covering even the society section can be dangerous, because cartel leaders may hang out at prominent social events and get angry if they are included in photos. In some cases, if they want the attention, they can be angered if they are left out.

The Inter-American Press Association condemned the photographer's killing and demanded authorities do a thorough investigation. It also said it was regretful that state authorities almost immediately linked him to organized crime.

"It's irresponsible that without doing a minimal investigation, authorities immediately linked the killings a vengeance by members of organized crime," it said.

Four journalists have been killed in Coahuila and two more have gone missing since 1989. None of the cases have been solved, the association said.

Press advocates have long called Mexico one of the most dangerous nations for reporters. But there isn't a single, agreed-upon figure on crimes against journalists.

The Committee to Protect Journalists says in its latest report published in February that 12 Mexican journalists went missing in 2006-2012 and that in the same period 14 were killed because of their work. Mexico's human rights commission lists 81 journalists who it says have been killed since 2000.

In 2012, Mexico's special prosecutor for crimes against freedom of expression said 67 journalists had been killed and 14 had disappeared in the country since 2006.

On Thursday, the lower house of congress approved a bill that would allow journalists to request that federal prosecutors and federal judges investigate attacks on them, and to establish cases in which such federal intervention would be obligatory. The bill was previously approved by the senate and has now been sent to the president for his signature.

Source: http://news.yahoo.com/mexican-newspaper-photographer-found-dead-153205581.html

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Saturday, April 27, 2013

April is Autism Awareness Month - The Valley News

? It is beneficial for all parents to know the signs of Autism and Autism Spectrum Disorder (ASD) and take actions early if they are concerned about how their child learns, plays, speaks or acts. Autism signs can be seen before age three (3) and last throughout a lifetime and can range from mild to severe.

?About 1 in 100 children has Autism or ASD which can cause significant social, behavioral and communication challenges,? said Lucianna Celotti, Coordinator of the Children with Special Health Care Needs Program of Essex County Public Health.

ASDs are a group of developmental disabilities categorized as Autistic Disorder, Asperger Syndrome and Pervasive Developmental Disorder-Not Otherwise Specified. Children with an ASD may have unusual reactions to sensory input like sounds, smells, tastes, looks or feels; repeat words or phrases; get upset by schedule changes; have difficulty understanding other peoples? feelings; avoid eye contact or prefer to be alone.

?It is important for parents who have concerns about their child?s development to talk to their child?s pediatrician. Children can greatly benefit from early detection and interventions,? said Celotti.

Essex County Public Health (ECPH) offers several programs for children with special health care needs. ?Our Early Intervention Program helps children ages birth through 3 years develop important social, behavioral and communication skills. Our services are provided based on a child?s individual need and are designed to help parents and families nurture their children and encourage skills.?

Learn more about the ECPH Early Intervention Program and other programs for children with special health care needs, visit www.co.essex.ny.us/PublicHealth or call Lucianna Celotti at (518) 873-3500.

Source: http://www.valleynewsadk.com/news/2013/apr/26/april-autism-awareness-month/

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Physicists, biologists unite to expose how cancer spreads

Apr. 26, 2013 ? Cancer cells that can break out of a tumor and invade other organs are more aggressive and nimble than nonmalignant cells, according to a new multi-institutional nationwide study. These cells exert greater force on their environment and can more easily maneuver small spaces.

The researchers report in the journal Scientific Reports that a systematic comparison of metastatic breast-cancer cells to healthy breast cells revealed dramatic differences between the two cell lines in their mechanics, migration, oxygen response, protein production and ability to stick to surfaces. The researchers discovered new insights into how cells make the transition from nonmalignant to metastatic, a process that is not well understood.

The resulting catalogue of differences could someday help researchers detect cancerous cells earlier and someday prevent or treat metastatic cancer, which is responsible for 90 percent of all cancer deaths, according to the study. It was conducted by a network of 12 federally funded Physical Sciences-Oncology Centers (PS-OC) sponsored by the National Cancer Institute. PS-OC is a collaboration of researchers in the physical and biological sciences seeking a better understanding of the physical and chemical forces that shape the emergence and behavior of cancer.

A multi-institutional study including researchers from Princeton University's Physical Sciences-Oncology Center found that metastatic cancer cells are more aggressive and nimble than nonmalignant cells. The Princeton group used silicon-etched microchannels (above) to study the behavior and physical properties of cancer cells. In this device, metastatic cancer cells enter the narrow channels at one end and accelerate as they rapidly move down the channel. Such high motility is a hallmark of metastasis and also indicative of high glucose metabolism, another hallmark of cancer. (Image by Guillaume Lambert)

"By bringing together different types of experimental expertise to systematically compare metastatic and nonmetastatic cells, we have advanced our knowledge of how metastasis occurs," said Robert Austin, professor of physics and leader of the Princeton PS-OC, along with senior co-investigator Thea Tlsty of the University of California-San Francisco.

Researchers with the Princeton PS-OC, for instance, determined that metastatic cells, in spite of moving more slowly than nonmalignant cells, move farther and in a straighter line, Austin said. The investigators studied the cells' behavior in tiny cell-sized chambers and channels etched out of silicon and designed to mimic the natural environment of the body's interior.

"The mobility of these metastatic cells is an essential feature of their ability to break through the tough membrane [the extracellular matrix] that the body uses to wall off the tumor from the rest of the body," Austin said. "These cells are essentially jail-breakers."

The tiny silicon chambers were built using Princeton's expertise in microfabrication technology -- typically used to create small technologies such as integrated circuits and solar cells -- and are an example of the type of expertise that physicists and engineers can bring to cancer research, Austin said. For the current study, the Princeton team included physics graduate students David Liao and Guillaume Lambert, and postdoctoral researchers Liyu Liu and Saurabh Vyawahare. They worked closely with a research group led by James Sturm, Princeton's William and Edna Macaleer Professor of Engineering and Applied Science and director of the Princeton Institute for the Science and Technology of Materials (PRISM) where the microfabrication was done.

The Princeton PS-OC also includes collaborators at the Johns Hopkins University School of Medicine, the Salk Institute for Biological Studies and the University of California-Santa Cruz.

The nationwide PS-OC program aims to crack the difficulty of understanding and treating cancer by bringing in researchers from physics, engineering, computer science and chemistry, said Nastaran Zahir Kuhn, program manager for the PS-OC at the National Cancer Institute.

Other notable findings from the paper include that metastatic cells recover more rapidly from the stress of a low-oxygen environment than nonmetastatic cells, which is consistent with previous studies. Although the low-oxygen environment did kill many of the metastatic cells, the survivors rebounded vigorously, underscoring the likely role of individual cells in the spread of cancer. The study also looked at total protein production and detected proteins in the metastatic cells that are consistent with the physical properties such as mobility that malignant cells need to invade the extracellular matrix.

"The PS-OC program aims to bring physical sciences tools and perspectives into cancer research," Kuhn said. "The results of this study demonstrate the utility of such an approach, particularly when studies are conducted in a standardized manner from the beginning."

For the nationwide project, nearly 100 investigators from 20 institutions and laboratories conducted their experiments using the same two cell lines, reagents and protocols to assure that results could be compared. The experimental methods ranged from physical measurements of how the cells push on surrounding cells to measurements of gene and protein expression.

"Roughly 20 techniques were used to study the cell lines, enabling identification of a number of unique relationships between observations," Kuhn said.

For example, a technique known as atomic force microscopy indicated that metastatic cells are softer than nonmalignant cells whereas a different technique, traction force microscopy, suggested that metastatic cells exert more force on their surroundings, Kuhn said. Together these two findings may indicate that metastatic cells can exert force to stick to, migrate on and remodel the tough extracellular matrix that surrounds the tumor, while remaining flexible enough to squeeze through small spaces in that membrane.

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The above story is reprinted from materials provided by Princeton University. The original article was written by Catherine Zandonella.

Note: Materials may be edited for content and length. For further information, please contact the source cited above.


Journal Reference:

  1. David B. Agus, Jenolyn F. Alexander, Wadih Arap, Shashanka Ashili, Joseph E. Aslan, Robert H. Austin, Vadim Backman, Kelly J. Bethel, Richard Bonneau, Wei-Chiang Chen, Chira Chen-Tanyolac, Nathan C. Choi, Steven A. Curley, Matthew Dallas, Dhwanil Damania, Paul C. W. Davies, Paolo Decuzzi, Laura Dickinson, Luis Estevez-Salmeron, Veronica Estrella, Mauro Ferrari, Claudia Fischbach, Jasmine Foo, Stephanie I. Fraley, Christian Frantz, Alexander Fuhrmann, Philippe Gascard, Robert A. Gatenby, Yue Geng, Sharon Gerecht, Robert J. Gillies, Biana Godin, William M. Grady, Alex Greenfield, Courtney Hemphill, Barbara L. Hempstead, Abigail Hielscher, W. Daniel Hillis, Eric C. Holland, Arig Ibrahim-Hashim, Tyler Jacks, Roger H. Johnson, Ahyoung Joo, Jonathan E. Katz, Laimonas Kelbauskas, Carl Kesselman, Michael R. King, Konstantinos Konstantopoulos, Casey M. Kraning-Rush, Peter Kuhn, Kevin Kung, Brian Kwee, Johnathon N. Lakins, Guillaume Lambert, David Liao, Jonathan D. Licht, Jan T. Liphardt, Liyu Liu, Mark C. Lloyd, Anna Lyubimova, Parag Mallick, John Marko, Owen J. T. McCarty, Deirdre R. Meldrum, Franziska Michor, Shannon M. Mumenthaler, Vivek Nandakumar, Thomas V. O?Halloran, Steve Oh, Renata Pasqualini, Matthew J. Paszek, Kevin G. Philips, Christopher S. Poultney, Kuldeepsinh Rana, Cynthia A. Reinhart-King, Robert Ros, Gregg L. Semenza, Patti Senechal, Michael L. Shuler, Srimeenakshi Srinivasan, Jack R. Staunton, Yolanda Stypula, Hariharan Subramanian, Thea D. Tlsty, Garth W. Tormoen, Yiider Tseng, Alexander van Oudenaarden, Scott S. Verbridge, Jenny C. Wan, Valerie M. Weaver, Jonathan Widom, Christine Will, Denis Wirtz, Jonathan Wojtkowiak, Pei-Hsun Wu. A physical sciences network characterization of non-tumorigenic and metastatic cells. Scientific Reports, 2013; 3 DOI: 10.1038/srep01449

Note: If no author is given, the source is cited instead.

Disclaimer: This article is not intended to provide medical advice, diagnosis or treatment. Views expressed here do not necessarily reflect those of ScienceDaily or its staff.

Source: http://feeds.sciencedaily.com/~r/sciencedaily/top_news/~3/fvNmb0CGB6A/130426152558.htm

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US tries new aerial tools in Caribbean drug fight

A balloon-like craft known as an aerostat is shown attached to the back of the U.S. Navy high speed vessel Swift docked in Key West, Florida, Friday, April 26, 2013. The U.S. Navy on Friday began testing two new aerial tools, borrowed from the battlefields of Afghanistan and Iraq, that officials say will make it easier to detect, track and videotape drug smugglers in action. (AP Photo/Ben Fox)

A balloon-like craft known as an aerostat is shown attached to the back of the U.S. Navy high speed vessel Swift docked in Key West, Florida, Friday, April 26, 2013. The U.S. Navy on Friday began testing two new aerial tools, borrowed from the battlefields of Afghanistan and Iraq, that officials say will make it easier to detect, track and videotape drug smugglers in action. (AP Photo/Ben Fox)

Stuart Orozco, flight operator with Aeronvironment Inc., prepares lo launch a UAS (unmanned aircraft system) named Puma from the deck of the U.S. Navy high speed vessel Swift near Key West, Florida, Friday, April 26, 2013. The U.S. Navy on Friday began testing two new aerial tools, borrowed from the battlefields of Afghanistan and Iraq, that officials say will make it easier to detect, track and videotape drug smugglers in action. (AP Photo/Ben Fox)

U.S. Navy Rear Admiral Sinclair Harris looks at a balloon-like craft known as an aerostat that is attached to the back of his high speed vessel Swift docked in Key West, Florida, Friday, April 26, 2013. The U.S. Navy on Friday began testing two new aerial tools, borrowed from the battlefields of Afghanistan and Iraq, that officials say will make it easier to detect, track and videotape drug smugglers in action. (AP Photo/Ben Fox)

ABOARD THE HIGH SPEED VESSEL SWIFT (AP) ? Drug smugglers who race across the Caribbean in speedboats will typically jettison their cargo when spotted by surveillance aircraft, hoping any chance of prosecuting them will vanish with the drugs sinking to the bottom of the sea.

That may be a less winning tactic in the future. The U.S. Navy on Friday began testing two new aerial tools, borrowed from the battlefields of Afghanistan and Iraq, that officials say will make it easier to detect, track and videotape drug smugglers in action.

One of the devices on display aboard the High Speed Vessel Swift is a large, white balloon-like craft known as an aerostat, which is tethered up to 2,000 feet (600 meters) above the ship's stern. The other tool on board for tests in the Florida Straits is a type of drone that can be launched by hand from the deck.

Together, they expand the ability of Navy and Coast Guard personnel to see what's beyond their horizon, according to officials from both military branches and the contractors hoping to sell the devices to the U.S. government.

The devices should allow authorities to detect and monitor suspected drug shipments from afar for longer sustained periods, giving them a better chance of stopping the smugglers. They also should allow them to make continuous videotapes that can be used in prosecutions.

"Being able to see them and watch what they are doing even before we get there is going to give us an edge," said Chief Chris Sinclair, assistant officer in charge of a law enforcement detachment on board the Swift, a private vessel leased to the Navy that is about to begin a monthlong deployment to the southwestern Caribbean, tracking the busy smuggling routes off Colombia and Honduras.

Crews practiced launching and operating both systems before a small contingent of news media on board the Swift, managing to bring back video of vessels participating in a mock surveillance mission as well as radar and video images of the fishing charters and sailboats that dot the choppy seas separating Cuba from the U.S. mainland.

The drone, officially a Puma All Environment unmanned aircraft system from Aerovironment Inc. of Simi Valley, California, splashed into the water on one landing and had to be retrieved. On the second round, it clacked noisily but intact on the shifting deck of the 321-foot ship. Rear Adm. Sinclair Harris, commander of the Navy's 4th Fleet, said the devices are necessary at a time when the service is making a transition to smaller, faster ships amid budget cuts.

The aerostat, formally the Aerostar TIF-25K and made by a division of Raven Industries Inc. of Sioux Falls, South Dakota, is filled with helium. It's an old technology, models of which have been used for decades, but it's packed with cameras and sensors that expand the ship's radar capability from about 5 miles (8 kilometers) to about 50 miles. That can help teams in an on-board control center to identify larger ships, which now would appear as just dots on the horizon, from as far as 15 miles (25 kilometers) away.

The Puma, meanwhile, can be sent out to inspect a vessel flagged by the larger aerostat and give a "God's eye view," of what's happening on board, a job usually handled by a plane or helicopter, said Craig Benson, director of business development for the company.

Both the aerostat and the drone have been used widely by the U.S. government for overseas actions, but Harris and others aboard the Swift said neither has been used before by the Navy to conduct counter-drug operations.

Unmanned aerial devices, however, are not new to the drug fight. U.S. Customs and Border Protection operates 10 Predator drones, including two based in Cape Canaveral, Florida, that patrol a wide swathe of the Caribbean through the Bahamas and down to south of Puerto Rico. It deployed one to the Dominican Republic last year for six weeks and has considered using one in Honduras. The others are used along the northern and southern borders of the United States.

The U.S. military has long been deeply involved in counter-drug operations in the Southern Hemisphere, coordinated by a multi-agency task force based in Key West, Florida. Navy ships and Air Force jets use their radar to track and run down smugglers, though for legal reasons the actual arrests are carried out by the Coast Guard, civilian agencies or officials from other countries.

In March, the military said it would reduce patrols and sorties in Latin America and the Caribbean because of the automatic spending cuts imposed by Congress, another argument for increased use of aerial surveillance devices like the aerostat and drone, officials said.

Representatives on the Swift from both contractors declined to say what their systems cost. But they said each can be run at a fraction of the cost of the fixed-wing planes or helicopters usually dispatched to check out suspected smugglers.

Associated Press

Source: http://hosted2.ap.org/APDEFAULT/3d281c11a96b4ad082fe88aa0db04305/Article_2013-04-27-Caribbean-Drug%20Drones/id-92ccea73924b433a8e4309188acc80f6

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Friday, April 26, 2013

Panasonic gussies up Lumix DMC-XS1 with 10 different designs

DNP Panasonic releases its $200 LUMIX DMCXS in 10 different color designs

It's that time of year again -- the gadgets of CES are finally starting to march into stores. Today's newest catalog item comes from Panasonic in the form of the 16.1-megapixel Lumix DMC-XS1 compact. Equipped with a 24mm wide-angle 5x optical zoom lens, this $200 point and shoot targets people looking to move beyond the hazy world of cellphone photography. Unlike some high-end smartphone cameras the DMC-XS1's 1/2.33-inch CCD sensor is limited to 720p video capture at 30 fps. It won't likely win over the hardcore paparazzo, but this compact's 10 flashy designs may manage to score some points with fledging shutterbugs.

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Source: http://feeds.engadget.com/~r/weblogsinc/engadget/~3/BmllZAEsmg0/

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Meteor shower webcast: Watch outside or onscreen

Tonight's meteor shower can be viewed outside, if you have little light pollution and clear skies. City folk and those with cloudy skies can watch NASA's livestream of the meteor shower.

By Tariq Malik,?Space.com / April 22, 2013

This sky map shows where to look in the eastern night sky for the 2013 Lyrid meteor shower. Vega (center) is one of the brightest stars in the sky, and Cygnus the Swan (lower left) contains enough bright stars to be easily spotted.

Starry Night Software / Space.com

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The annual Lyrid meteor shower may have peaked overnight on Sunday and Monday, but if you missed the celestial fireworks show don't fret. NASA's got you covered.

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Scientists at NASA's Marshall Space Flight Center (MSFC) in Huntsville, Ala., will broadcast live images of the Lyrid meteor shower tonight and early Tuesday (April 22 and 23) for stargazers stuck with bad weather or light-polluted night skies. ?

The NASA broadcast will begin at 8:30 p.m. EDT (0030 April 23) and run throughout the evening. You can watch the Lyrid meteor shower webcast on SPACE.com courtesy of NASA's MSFC feed.

"If you'd like to catch a last look at 2013 Lyrid meteor shower, this is your chance!" MSFC officials said in an announcement today. "Although a bright moon may interfere with viewing, you should still be able to see Lyrid meteors at an anticipated rate of 10-20 meteors per hour."

This year, the Lyrid meteor display runs from April 16 through April 26, though it peaked overnight on April 21 and 22. Because the moon is bright in the evening sky, the best time to look for the Lyrids is in the wee morning hours before dawn, after the moon has set but before the sun rises.

The Lyrid meteor shower occurs each year in mid-April when the Earth passes through a dusty lane of debris left over from Comet Thatcher, which is also known as C/1861 G1 Thatcher. The comet orbits the sun once every 415 years. The Lyrids are created when the comet's dust streaks through Earth's atmosphere at speeds of up to 110,000 mph (177,027 kph). ?

The Lyrids get their name because they appear to radiate out of the constellation Lyra. Humans have been observing the "shooting stars" display for more than 2,600 years, NASA scientists have said.

Editor's note:?If you snap a great photo Lyrid meteor shower that?you'd like to share for a possible story or image gallery, send photos, comments and your name and location to managing editor Tariq Malik at?spacephotos@space.com.

Email Tariq Malik at tmalik@space.com or follow him?@tariqjmalik?and?Google+.?Follow us?@Spacedotcom,?Facebook?and?Google+. Original article on?SPACE.com.

Copyright 2013 SPACE.com, a TechMediaNetwork company. All rights reserved. This material may not be published, broadcast, rewritten or redistributed.

Source: http://rss.csmonitor.com/~r/feeds/science/~3/LISY9xYW2rk/Meteor-shower-webcast-Watch-outside-or-onscreen

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Rethinking early atmospheric oxygen

Thursday, April 25, 2013

A research team of biogeochemists at the University of California, Riverside has provided a new view on the relationship between the earliest accumulation of oxygen in the atmosphere, arguably the most important biological event in Earth history, and its relationship to the sulfur cycle.

A general consensus exists that appreciable oxygen first accumulated in Earth's atmosphere around 2.4 to 2.3 billion years ago. Though this paradigm is built upon a wide range of geological and geochemical observations, the famous "smoking gun" for what has come to be known as the "Great Oxidation Event" (GOE) comes from the disappearance of anomalous fractionations in rare sulfur isotopes.

"These isotope fractionations, often referred to as 'mass-independent fractionations,' or 'MIF' signals, require both the destruction of sulfur dioxide by ultraviolet energy from the sun in an atmosphere without ozone and very low atmospheric oxygen levels in order to be transported and deposited in marine sediments," said Christopher T. Reinhard, the lead author of the research paper and a former UC Riverside graduate student. "As a result, their presence in ancient rocks is interpreted to reflect vanishingly low atmospheric oxygen levels continuously for the first ~2 billion years of Earth's history."

However, diverse types of data are emerging that point to the presence of atmospheric oxygen, and, by inference, the early emergence of oxygenic photosynthesis hundreds of millions of years before these MIF signals disappear from the rock record. These observations motivated Reinhard and colleagues to explore the possible conditions under which inherited MIF signatures may have persisted in the rock record long after oxygen accumulated in the atmosphere.

Using a simple quantitative model describing how sulfur and its isotopes cycle through the Earth's crust, the researchers discovered that under certain conditions these MIF signatures can persist within the ocean and marine sediments long after O2 increases in the atmosphere. Simply put, the weathering of rocks on the continents can transfer the MIF signal to the oceans and their sediments long after production of this fingerprint has ceased in an oxygenated atmosphere.

"This lag would blur our ability to date the timing of the GOE and would allow for dynamic rising and falling oxygen levels during a protracted transition from an atmosphere without oxygen to one rich in this life-giving gas," Reinhard said.

Study results appear in Nature's advanced online publication on April 24.

Reinhard explained that once MIF signals formed in an oxygen-poor atmosphere are captured in pyrite and other minerals in sedimentary rocks, they are recycled when those rocks are later uplifted as mountain ranges and the pyrite is oxidized.

"Under certain conditions, this will create a sort of 'memory effect' of these MIF signatures, providing a decoupling in time between the burial of MIF in sediments and oxygen accumulation at Earth's surface," he said.

According to the researchers, the key here is burying a distinct MIF signal in deep sea sediments, which are then subducted and removed from Earth's surface.

"This would create a complementary signal in minerals that are weathered and delivered to the oceans, something that we actually see evidence of in the rock record," said Noah Planavsky, the second author of the research paper and a former UC Riverside graduate student now at Caltech. "This signal can then be perpetuated through time without the need to generate it within the atmosphere contemporaneously."

Reinhard, now a postdoctoral fellow at Caltech and soon to be an assistant professor at Georgia Institute of Technology, explained that although the researchers' new model provides a plausible mechanism for reconciling recent conflicting data, this can only occur when certain key conditions are met ? and these conditions are likely to have changed through time during Earth's long early history.

"There is obviously much further work to do, but we hope that our model is one step toward a more integrated view of how Earth's crust, mantle and atmosphere interact in the global sulfur cycle," he said.

Timothy W. Lyons, a professor of biogeochemistry at UCR and the principal investigator of the research project noted that this is a fundamentally new and potentially very important way of looking at the sulfur isotope record and its relationship to biospheric oxygenation.

"The message is that sulfur isotope records, when viewed through the filter of sedimentary recycling, may challenge efforts to precisely date the GOE and its relationship to early life, while opening the door to the wonderful unknowns we should expect and embrace," he said.

###

University of California - Riverside: http://www.ucr.edu

Thanks to University of California - Riverside for this article.

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Source: http://www.labspaces.net/127923/Rethinking_early_atmospheric_oxygen

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