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Researchers may have found the "Mona Lisa" model's skeleton. (Photo : Wikimedia Commons) Scientists are on a mission to find the model for the "Mona Lisa," they plan to dig up centuries-old graves and digitally reconstruct the face of a choice skeleton. Experts believe the model for the famous "Mona Lisa" painting was Leonardo da Vinci's neighbor, Lisa Gherardini Del Giocondo, ANSA reported. Several skeletons found in a Florence convent last year could be the remains of the model. Experts plan to identify the most likely candidate and compare the DNA with a body believed to be her son. "Right...

Do Young C-14 Results Reflect Contamination? by Jake Hebert, Ph.D. * The presence of carbon-14 (C-14) in specimens that are supposedly millions of years old is a serious problem for believers in an old earth. C-14 is a radioactive variety or “isotope” of carbon that eventually decays into nitrogen. Because this occurs relatively quickly, no C-14 should be detected in any specimen that is more than about 100,000 years old.1 The fact that C-14 has long been detected in coal, oil, fossilized wood, and natural gas samples is genuinely surprising to those who believe these samples to be millions of...

Enlarge Image Nuclear fallout. Radioactive carbon-14 atoms released by atomic bombs are helping scientists determine the birthdays of new neurons in the hippocampus (inset). Credit: Spalding et al., Cell (2013);(inset) Weissman, Livet, Sanes, and Lichtman/Harvard University The mushroom clouds produced by more than 500 nuclear bomb tests during the Cold War may have had a silver lining, after all. More than 50 years later, scientists have found a way to use radioactive carbon isotopes released into the atmosphere by nuclear testing to settle a long-standing debate in neuroscience: Does the adult human brain produce new neurons? After working to...

From the AGU weekly highlights: Large solar proton event explains 774-775 CE carbon-14 increase Tree ring records indicate that in 774-775 CE, atmospheric carbon-14 levels increased substantially. Researchers suggest that a solar proton event may have been the cause. In solar proton events, large numbers of high-energy protons are emitted from the Sun, along with other particles. If these particles reach EarthÂ’s atmosphere, they ionize the atmosphere and induce nuclear reactions that produce higher levels of carbon-14; the particles also cause chemical reactions that result in depletion of ozone in the ozone layer, allowing harmful ultraviolet radiation to reach the...

“Life exists in the universe only because the carbon atom possesses certain exceptional properties.” -James Jeans Here on Earth, every living thing is based around four fundamental, elemental building blocks of life: hydrogen, oxygen, nitrogen and, perhaps most importantly, carbon.Image Credit: Robert Johnson / University of Pennsylvania. From diamonds to nanotubes to DNA, carbon is indispensable for constructing practically all of the most intricate structures we know of. Most of the carbon in our world comes from long-dead stars, in the form of Carbon-12: carbon atoms containing six neutrons in their nucleus. About 1.1% of all carbon is Carbon-13, with one...

The long, slow decay of carbon-14 allows archaeologists to accurately date the relics of history back to 60,000 years. And while the carbon dating technique is well known and understood (the ratio of carbon-14 to other carbon isotopes is measured to determine the age of objects containing the remnants of any living thing), the reason for carbon-14's slow decay has not been understood. Why, exactly, does carbon-14 have a half-life of nearly 6,000 years while other light atomic nuclei have half-lives of minutes or seconds? (Half-life is the time it takes for the nuclei in a sample to decay to...

Household and personal products making claims about the sustainability of their ingredients may not be all they seem. According to analysis by US researchers, many such products contain surprising amounts of petroleum-derived ingredients. Some 'green' products contained over 50 per cent petroleum-based carbon components Researchers at Seventh Generation in Vermont - which makes its own range of household products from predominantly plant-derived ingredients - have been using carbon-14 analysis to reveal the origins of components in  liquid laundry detergent, washing up liquid, and hand wash products. Their results - particularly for products making sustainability claims - were quite surprising. For products sold in...

Caption: Professor Gerry McCormac and Dr Paula Reimer pictured in the 14 Chrono Centre at Queen's University Belfast. Staff at the Centre have been involved in the creation of a new calibration curve, which extends back 50,000 years. Credit: Queen's University Belfast Usage Restrictions: Only to be used with full caption and reference to Queen's University Belfast. Researchers at Queen's University have helped produce a new archaeological tool which could answer key questions in human evolution. The new calibration curve, which extends back 50,000 years is a major landmark in radiocarbon dating-- the method used by archaeologists and geoscientists to...

Carbon 14 from Cold War–era nuclear bomb tests allowed researchers to track cell birth By monitoring carbon 14 emitted from Cold War–era nuclear bomb tests, researchers found that heart muscle cells continue to divide throughout adulthood, shows a study appearing in the April 3 Science. The low-level cell renewal may eventually be exploited to treat damaged hearts, says study coauthor Jonas Frisén of the Karolinska Institute in Stockholm. The finding contradicts the belief of many scientists that the heart muscle cells sticking around until the end were present at birth. “The dogma has always been that cell division in the...

PRESS RELEASE: Los Alamos National Laboratory team of scientists prove carbon 14 dating of the Shroud of Turin wrong COLUMBUS, Ohio, August 15 — In his presentation today at The Ohio State University’s Blackwell Center, Los Alamos National Laboratory (LANL) chemist, Robert Villarreal, disclosed startling new findings proving that the sample of material used in 1988 to Carbon-14 (C-14) date the Shroud of Turin, which categorized the cloth as a medieval fake, could not have been from the original linen cloth because it was cotton. According to Villarreal, who lead the LANL team working on the project, thread samples they...

Read the entire article at Possibly the Biggest Radiocarbon Dating Mistake Ever to see it formatted, with images, notes and cited works. I asked my teacher about it but was ridiculed for not being scientific.” -- High School Student from Alaska It may well go down as the biggest radiocarbon dating mistake in history; not because there is anything wrong with the measurement process (there may not have been); not because there is anything inherently wrong with carbon 14 dating (there is not); not because of shoddy sample taking (which indeed was shoddy); not because of red flags that should...

(6) SUNSPOTS AND CLIMATE B. Geerts and E. Linacre http://www-das.uwyo.edu/~geerts/cwx/notes/chap02/sunspots.html Sunspot cycle Sunspots have a diameter of about 37,000 km and appear as dark spots within the photosphere, the outermost layer of the Sun. The photosphere is about 400 km deep, and provides most of our solar radiation. The layer is about 6,000 degrees Kelvin at the inner boundary and 4,200 K on the outside. The temperature within sunspots is about 4,600 K. The number of sunspots peaks every 11.1 years. There is a strong radial magnetic field within a sunspot, as implied in the picture, and the direction of...

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