Headlines of the day
Ex-Florida prison boss: Drunken orgies tainted system (CNN)
What gave it away?
Falling moose nearly takes out trooper ( Anchorage Daily News)
And where is squirrel?
UPDATE: Hardwired for love: Are robots the sex partners of the future? (Drudge)
A future where even the lawyers get some.
Meth Deposited in ATM, Woman Jailed...(AP)
Talk about a speedy transaction...
Mummified Corpse Found in Bathtub of Arizona Renter (Breitbart.com)
“Oh yeah? Check the lease.
Newsweek: We may still be (unconscious) racists
Really?
Today’s episode of Gil Scott-Heron’s “And Whitey’s on the Moon.”
Scientists prove Napoleon not poisoned
Researchers measured arsenic levels using nuclear reactor to irradiate hair
ROME - Italian scientists say they have proved Napoleon was not poisoned, scotching the legend the French emperor was murdered by his British jailors.
Napoleon's post-mortem said he died of stomach cancer aged 51, but the theory he was assassinated to prevent any return to power has gained credence in recent decades as some studies indicated his body contained a high level of the poison arsenic.
"It was not arsenic poisoning that killed Napoleon at Saint Helena," said researchers at the University of Pavia who tested the theory the British killed him while he was in exile on the South Atlantic island in 1821.
The Italian research — which studied hair samples from various moments in his life which are kept in museums in Italy and France — showed Napoleon's body did have a high level of arsenic, but that he was already heavily contaminated as a boy.
The scientists used a nuclear reactor to irradiate the hairs to get an accurate measure of the levels of arsenic.
Looking at hairs from several of Napoleon's contemporaries, including his wife and son, they found arsenic levels were generally much higher than is common today.
"The result? There was no poisoning in our opinion because Napoleon's hairs contain the same amount of arsenic as his contemporaries," the researchers said in a statement published on the university's website.
The study found the samples taken from people living in the early 1800s contained 100 times as much arsenic than the current average. Glues and dyes commonly used at the time are blamed for high environmental levels of the toxic element.
"The environment in which people lived in the early 1800s evidently caused the intake of quantities of arsenic that today we would consider dangerous," the scientists said.
One theory was that Napoleon was poisoned accidentally by arsenic vapor from dyes in his wallpaper at Saint Helena, but the study showed there was no massive increase in arsenic levels in his latter years.
"It is clear that one cannot talk about a case of poisoning, but of a constant absorption of arsenic," the researchers said.
Napoleon had been exiled once before — on the Italian island of Elba after his failed invasion of Russia. But he returned to France and was finally defeated at Waterloo in 1815 after which he was sent to the much more remote Saint Helena.
Golly, we’re glad they cleared that up.
Lord Vader Has No Comment
New Cosmic Theory Unites Dark Forces
Michael Schirber
Special to SPACE.com
SPACE.com Mon Feb 11, 6:46 AM ET
The two biggest mysteries in cosmology may be one. A new theory says that dark matter and dark energy could arise from a single dark fluid that permeates the whole universe. And this could mean Earth-based dark matter searches will come up empty.
Dark matter, as originally hypothesized, is extra hidden mass that astrophysicists calculate is necessary for holding together fast-turning galaxies. The most popular notion is that this matter is made of some yet-to-be-identified particle that has almost no interactions with light or ordinary matter. Yet it seems to be everywhere, acting as a scaffolding for galaxy clusters and the whole structure of the universe.
On the other hand, dark energy is needed to explain the more recently-discovered acceleration of the universe's expansion. It supposedly exists all throughout space, delivering a pressure that counteracts gravity.
It's counterintuitive that one substance could be both a gravitational anchor for galaxies and anti-gravity force for the universe. However, HongSheng Zhao of the University of St Andrews in Scotland claims that a fluid-like dark energy can act like dark matter when its density becomes high enough.
"Dark energy is a property of the vacuum — of fields that we do not easily see," Zhao told Space.com. "From it, we can derive the dark matter effect."
Zhao compares this dark fluid to Earth's atmosphere. Atmospheric pressure causes air to expand, but part of the air can collapse to form clouds. In the same way, the dark fluid might generally expand, but it also could collect around galaxies to help hold them together.
Unification
Zhao is not the first theorist to try to bring dark energy and dark matter under the same framework.
The type of dark fluid that Zhao is looking at is similar to one that Pedro Ferreira of the University of Oxford and his colleagues devised a few years ago.
"[Our theory] involves positing a preferred time direction, in some sense a special time frame," Ferreira said. "It has the interesting effect of modifying Einstein's theory of general relativity."
The idea is similar to the "ether," an invisible medium that physicists once thought light waves travelled through. Einstein's relativity did away with the need for such a medium, but cosmologists have recently found that an ether-like substance can mimic dark matter.
The presence of such a substance changes the way gravity works. This is most noticeable in the distant outskirts of a galaxy, where the galaxy's gravitational pull would be expected to be small, but the ether makes it much stronger.
The ether "effectively softens space-time in regions of low [gravitational] acceleration making it more sensitive to the presence of mass than usual," Ferreira explained.
Zhao has refined this approach and found that it can match a lot of astronomical data, as reported in a recent article in Astrophysical Journal Letters.
"I like [Zhao's model] because it shows that these theories are predictive and, if worked out in detail, can be tested properly against experiment," Ferreira said.
For one, Zhao's fluid divides itself into a dark energy part and a dark matter part with the same ratio that is seen from observations (dark energy is about 75 percent of the universe's mass-energy content, while dark matter is about 21 percent and normal matter makes up the last 4 percent).
Although the fluid is all around us, Zhao found that it does not affect the motion of Earth or the other planets, which is "reassuring," he said, because data shows that our solar system obeys traditional gravity to very high accuracy.
But the fluid does affect the speed at which galaxies can rotate. Some 75 years ago, astronomers noticed that galaxies were turning faster than would be expected from the amount of normal light-emitting matter they contained. The answer seemed to require some form of unseen dark matter.
However, Zhao has shown that his fluid can keep galaxies from flying apart just as well as dark matter can.
Zhao has also tested his model against the bullet cluster of galaxies, where a massive collision appears to have stripped hot gas from its dark matter envelope. This "naked" dark matter was seen as iron-clad proof for traditional dark matter theories, but Zhao claims that his fluid can reproduce the same effect.
Christian Boehmer from University College London thinks it "compelling" that Zhao's model can reproduce so much galaxy data.
If the dark fluid is mimicking dark matter, then scientists are searching in vain for the elusive dark matter particle, often called a WIMP (for weakly interacting massive particle).
Currently, several experiments are trying to detect a rare collision of a WIMP on Earth or observe gamma rays from distant WIMP self-annihilations.
"Direct detections will be more difficult," Zhao said. WIMPs may still exist, but there won't be as many of them as predicted.
Without WIMPs to worry about, the dark fluid could make scientists' jobs easier.
But not many cosmologists are ready to abandon dark matter just yet. The dark fluid idea is still fairly new, so some issues have yet to be worked out, whereas dark matter is a fairly mature theory.
"The current [dark matter] model provides the best fit to the data and is therefore the best model at hand," Boehmer said.
However, Boehmer agrees that having two unknowns — dark matter and dark energy — make up 95 percent of the universe is a bit embarrassing for cosmology.
"Frankly speaking, these are just fancy words we use to name something we do not understand," he said.
If a simpler model (with a single word) can explain all the data, then cosmologists will gladly accept it, Boehmer said.
"The type of dark fluid that Zhao is looking at is similar to one that Pedro Ferreira of the University of Oxford and his colleagues devised a few years ago". Let’s see, that called for shoe polish and eye of newt, if we remember correctly.
Is this a pitch for a prehistoric yogurt ad?
How Did Huge Dinosaurs Find Enough Food? Did Bacteria Aid Their Digestion?
ScienceDaily (Feb. 12, 2008) — Scientists from the University of Bonn are researching which plants giant dinosaurs could have lived off more than 100 million years ago. They want to find out how the dinosaurs were able to become as large as they did. In fact such gigantic animals should not have existed according to general rules of ecology.
Dinosaur digestion
Take 200 milligrammes of dried and ground equisetum, ten millilitres of digestive juice from sheep's rumen, a few minerals, carbonate and water. Fill a big glass syringe with the mix, clamp this into a revolving drum and put the whole thing into an incubator, where the brew can rotate slowly. In this way you obtain the artificial 'dinosaur rumen'. With this apparatus (also used as a 'Menke gas production technique' in assessing food for cows) Dr. Jürgen Hummel from the Bonn Institute of Animal Sciences (Bonner Institut für Tierwissenschaften) is investigating which plants giant dinosaurs could have lived off more than 100 million years ago, since this is one of the pieces which are still missing in the puzzle involving the largest land animals that ever walked the earth. The largest of these 'sauropod dinosaurs' with their 70 to 100 tonnes had a mass of ten full grown elephants or more than 1000 average people.
Larger than permitted
How the dinosaurs could ever attain this size is something which scientists from Germany and Switzerland are investigating. The Bonn palaeontologist, Professor Martin Sander, the coordinator of the research group 'Biology of the Sauropod Dinosaurs: The Evolution of Gigantism', says, 'There is a law to which most animals living today conform. The larger an animal, the smaller the density of the population, i.e. the fewer animals of the same species there are per square kilometre.' The larger an animal is, the larger the amount of food it has to have in order to survive. Therefore a specific area can only feed a certain maximum number of animals.
At the same time there is a lower limit to the density of population. If this is undercut, the species dies out: 'In this case diseases can rapidly wipe out the whole stock. Moreover, finding a mate becomes difficult,' Martin Sander explains. An animal like the 100-tonne argentinosaurus should have normally not had this 'minimum population density', actually it should not have been able to exist. But there are hypotheses for this apparent paradox: for example the giant dinosaurs presumably had a metabolism that was lower than that of mammals. In this context it is unclear how nutritious the plants were that formed their diet.
This question is being investigated by Dr. Jürgen Hummel in conjunction with Dr. Marcus Clauss from the University of Zurich. 'We assume that the herbivorous dinosaurs must have had a kind of fermenter, similar to the rumen in cows today.' Almost all existing herbivores digest their food by using bacteria in this way. The panda is the exception. Because the panda is not like this its digestion is inefficient. It stuffs bamboo leaves into its mouth all day long, in order to meet its energy needs, despite the fact that it does not move about much, thereby saving energy.
Jürgen Hummel transforms glass syringes into simple fermenters, which he fills with bacteria from the sheep's rumen. 'These micro-organisms are very old from an evolutionary point of view; we can therefore assume that they also existed in the past,' he explains. To the mix of bacteria he adds dried and ground food plants: grass, foliage or herbs which still form part of animals' diet, and for comparison equisetum, Norfolk Island pine or ginkgo leaves, i.e. parts of plants which have been growing for more than 200 million years on earth. The gas formed during the fermentation process presses the plunger out of the syringes. Jürgen Hummel can therefore read the success of the fermentation process directly off their scales. This is measured according to a simple rule: the more gas is produced, the 'higher the quality' of the food.
Equisetum is bad for the teeth
These 'old' plants stand their ground surprisingly well compared to today's flora. 'The difference is not as great as might be expected,' Jürgen Hummel emphasises. The bacteria digest ginkgo even better than foliage, but they seem to prefer equisetum most. With it gas production is even higher than with some grasses. Nevertheless, equisetum figures in the diet of comparatively few animals. The reason is that in addition to the toxins present in many modern species it wears down animals' teeth too much. 'Equisetum contains a lot of silicates,' Jürgen Hummel says. 'It acts like sand paper.'
However, many dinosaurs did not have any molars at all. They just pulled up their food and gulped it down. The mechanical break-up may have been carried out by a 'gastric mill'. Similar to today's birds, dinosaurs may have swallowed stones with which they ground the food to a paste with their muscular stomach. However, there are no clear indications of this. Only recently the Bonn palaeontologist Dr. Oliver Wings doubted that dinosaurs had bezoar stones, at least this assumption could not be verified from fossil findings.
The results of the research have now been published in the journal 'Proceedings of the Royal Society B'.
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