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Installed on board the ISS In September 2009, the DECLIC instrument developed by CNES has delivered its first results. With it, scientists were able to identify how temperature the water becomes supercritical water.
373.995 ° C, the temperature “critical” water
373.995 ° C. It is above this temperature as the water in pressure (1) becomes supercritical water, ie becomes liquid and gas at once. This critical temperature was obtained through laboratory DECLIC (2) in Space Station International.
“The absolute measure must still be refined, but it is a first in microgravity!” Bridge to rejuit Gabriel, head of mission DECLIC at CNES. On Earth With the severity it was simply impossible to make such comments. “In approaching this critical temperature, the water crashed under its own weight and laminates, said Bernard Zappoli, program manager of Sciences material CNES. Consequence: the medium is not homogeneous and can not locate the critical temperature with precision. ”
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Most amber deposits are located in America North and Eurasia. Only a few amber Nonfossiliferous were known to the ancient Gondwana. Also discovered in Ethiopia in 2005, the first amber fossil in Africa, dating from about 95 million years ago, she was of primary importance.
About twenty of German researchers, French, Austrian, Ethiopian, Italian, English and American, has worked to study the geology of the deposit of the amber and fossils it contains. The study of insects led by Vincent Perrichot, paleontologist at Geosciences Rennes, revealed the great diversity and ecology of species, including a primitive ant, the oldest of Gondwana. This will better understand the early evolution of these organisms and trophic interactions within this ecosystem former. These results have just been published in PNAS (Proceedings of the National Academy of Sciences of the USA).
Tropical forests, composed of conifers and even archaic populated by dinosaurs, grew in the Cretaceous (1) in this region of Ethiopia already famous for being considered one of the “cradle of humanity”.
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Box 117, Mendeleyev’s periodic table has finally found its occupant. It remains to find a name for this new element.
The superheavy element 116 (Ununhexium) and 118 (Ununoctium) of the periodic table were discovered in 2000 and 2006 by an international collaboration of American and Russian physicists. But there was still a box to complete the periodic table of elements, box 117, located in the penultimate column, a link is established between these two elements. It has now been done since the same team just synthesize Superheavy element 117 protons (Z = 117).
The race for superheavy elements, whose nuclei contain more than 110 protons, was launched there is more than a dozen years ago. They are synthesized from the reaction of fusion of two lighter nuclei.
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Twelve bottles of champagne and 8,000 euros are at stake for mathematical puzzles about magic squares.
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The discovery of six planets retrograde throws a stone into the pond theories of planetary formation.
All the planets of the Solar System orbit the Sun in the same direction as it rotates around its axis. We thought it was the same for extrasolar planets around their stars, but six planets come to be caught spinning in the opposite direction to the rotation of their stars. The discovery of these so-called retrograde motion is in response to observations made largely by Amaury Triaud and Didier Queloz of the Geneva Observatory, and Andrew Cameron of the University of St Andrews (Scotland). It poses a serious problem for theories of planetary formation, which predict that planets in retrograde motion should not come into being.
Indeed, a planetary system is born from a cloud of gas and dust that spins as it contracts and flattens. At the center star is born, and the residual disk formed later planets. These must therefore rotate in the same direction as the star, and have orbits roughly in the same plane.
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In a warming climate, scientists are-with their models-an intensification of the water cycle. A pair of Australian researchers shows that the consequences of this intensification will find in the ocean.
In regions where the contributions of significant rain, water from the ocean surface is less salty, while in others, the salinity seems to go up. Work published in the Journal of Climate Of the American Meteorological Society.
Paul Durack and Susan Wijffels, working at CSIRO. The equivalent in Australia of the French CNRS. They analyzed 1.6 million available for registration since 1950, including data recorded daily by the 3254 buoys ARGO that measure temperature, salinity and ocean currents. These buoys roam the oceans of Earth, plunging steadily to two thousand meters depth to save profiles, before rising to the surface to transmit to satellites.
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The fossils and the surrounding matrix can provide important information about how our world was millions of years ago. The fossils of angiosperms, or flowering plants (which currently are the most common plants) first appeared in the fossil record 140 million last few years.
Dana Royer of Wesleyan University, Connecticut, and his colleagues wanted to determine whether it is possible to identify aspects of the life cycle of a plant fossil, such as its growth strategy based on their morphology rather than from parent has received. Questions were raised whether this technique could confirm the suspicion that these primitive plants were fast-growing species, and answer the question of how common the plant was 100 million years ago the strategy of its life cycle.
The study authors conducted a series of analysis that led to the measurement of 179 fossil specimens of 30 species from three paleontological sites of between 105 and 110 million years old located in areas other than the United States.
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People in developed countries remain in good health more than a decade, keeping their parents, not because it has slowed or reversed the aging, but because they remain healthy into older age.
They live longer because they reach old age in better health. But once it begins the final process of aging, including dementia and heart disease, remain at the same rate of decline of their parents. Only postpones the onset of such deterioration.
This and other interesting issues are discussed in a study by demographer James Vaupel, who directs the Center on the Demography of Aging at Duke University and holds academic posts at the Max Planck Institute for Demographic Research in Rostock, Germany, and Public Health Institute at the University of Southern Denmark.
The best current health at older ages in developed nations is due to improvements in public health to improve living conditions and prevent diseases and medical advances. Over the past 170 years, in countries with longer life expectancies, the lifetime average has grown at a rate of 2.5 years per decade, or about six hours per day.
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A team of scientists has found evidence of a catastrophic event that they believe was responsible for stopping the birth of stars in a galaxy in the early universe.
The researchers, led by the Department of Physics, University of Durham, believe that the massive galaxy SMM J1237 +6203 was subjected to a massive series of explosions billions of times more powerful than that caused by any atomic bomb. The explosions took place every second for millions of years.
That fierce bombardment scattered cosmic gas necessary for the formation of new stars, helping them to escape the gravitational pull of the galaxy, and thus limiting its development. The research team believes that the huge machine gun fire was caused by debris catapulted from near the galactic black hole or the stellar winds generated by dying stars exploding as supernovae.
The galaxy SMM J1237 +6203 is located in the constellation Ursa Major, and is so far away that we see it as it was 10 000 million years ago, or three billion years after the Big Bang when the universe was only a quarter of its present age.
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The biochemist Daniel Schabacker, Argonne National Laboratory, could be considered the Sherlock Holmes of bioterrorism. Although there is no magnifying glass pipe when you try to discover the culprit, has a tool to deduct much more powerful: the biochip.
Using biochips offers Schabacker and colleagues at Loyola University in Chicago, the possibility of identifying “signature” of biological agents that can be used for acts of bioterrorism, especially the bacteria that causes Anthrax (anthrax), Bacillus anthracis.
Although some scientists have used DNA analysis to identify particular strains of Anthrax bacteria, biochips are able to help decisively to scientists and government officials to find out how they have been cultivated Anthrax bacteria tested, thereby reducing the amount of potential suspects.
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