Mount Etna erupts: video captures moment volcano blew its top

Molten lava poured down Mount Etna’s slopes on during the eruption, which lasted an-hour-and-a-half.

Ash landed close to villages at the foot of the volcano but no damage was reported. The eruption did not cause any interruption to air traffic.When Mount Etna last erupted more than two weeks ago, a four mile-long plume of ash forced the temporary closure of the airport in Catania – Sicily’s second largest city.The volcano has been active for around half a million years. In 1669 more than 20,000 people were killed during Etna’s most violent eruption.

Although Etna is in a constant active state its slopes teem with farms and vineyards, thanks to its rich volcanic soil.

In the past, Italian authorities have used explosives, concrete dams, and ditches to divert lava flows away from local settlements.Etna is derived from the Latin word ‘Aetna’ and during ancient times was considered the home of the god of fire, Vulcan

via Mount Etna erupts: Amazing video captures moment volcano blew its top – Yahoo! News UK.

39 million may be evacuated from Tokyo

Despite the fact that it long since disappeared from major news headlines, an editorial in one of Japan’s leading newspapers warns that the Fukushima crisis is still at a critical stage and that the Japanese government has drawn up contingency plans for the potential evacuation of Greater Tokyo’s 39 million residents.

Fukushima’s reactor number 4, which holds 75% as much nuclear fuel as the entire Chernobyl complex did prior to its meltdown, 460 tons in total, is at risk of collapse. With the roof of the complex blown away, if the storage pool for the spent fuel, which is housed on the 3rd and 4th floors of the building, were to fracture then the nuclear fuel would overheat and explode, spreading radioactive fallout over a wide area.
Both the U.S. Nuclear Regulatory Commission (NRC) and French nuclear energy company Areva have warned that reactor number 4 is the “weakest link” out of the entire Fukushima complex. The Tokyo Electric Power Company has resisted calls to bury the spent fuel rods in concrete, citing the cost, but an editorial in Japan’s Mainichi Daily News quotes government insiders who warn that the potential collapse of the reactor is “a grave concern.”
“Because sea water was being pumped into the reactor, the soundness of the structure (concrete corrosion and deterioration) was questionable. There also were doubts about the calculations made on earthquake resistance as well,” said one government source familiar with what took place at the time. “It’s been suggested that the building would be reinforced, and spent fuel rods would be removed from the pool under those conditions. But fuel rod removal will take three years. Will the structure remain standing for that long?”
As part of contingency planning for the collapse of reactor number 4, the Japanese government has drawn up a blueprint for forcibly evacuating 39 million residents out of the Tokyo metropolitan area.
“The worse-case scenario drawn up by the government includes not only the collapse of the No. 4 reactor pool, but the disintegration of spent fuel rods from all the plant’s other reactors. If this were to happen, residents in the Tokyo metropolitan area would be forced to evacuate,” according to the editorial by senior writer Takao Yamada.
The radiation exposure Tokyo residents are already receiving as a result of the disaster are certain to cause devastating health effects for decades to come…
- prison planet.

How Usain Bolt can run faster — effortlessly

Usain Bolt can achieve faster running times with no extra effort on his part or improvement to his fitness, according to a study published today in Significance, the magazine of the Royal Statistical Society and the American Statistical Association. Cambridge Professor of Mathematical Sciences John D. Barrow illustrates how, based on concrete mathematical evidence, Bolt can cut his world record from 9.58 seconds to 9.45.

Usain Bolt holds the current 100m world record, at 9.58s, and has been described as the best sprinter there has ever been, dramatically reducing his running times since he first won the world record in 2008. Previous scientific studies have been carried out aiming to predict his maximum speed, yet have failed to take all the relevant factors into account, and Bolt has already surpassed the speeds they predicted.

Today’s Significance study highlights the three key factors instrumental in improving Bolt’s performance, which combined produce an improvement of 0.13s.

Firstly, Bolt’s reaction time is surprisingly poor, in fact one of the longest of leading sprinters. By responding to the gun as quickly as possible without triggering a false start, with 0.10s, he would shave 0.05s off his world record to 9.53s.

Secondly, advantageous wind conditions can help athletes improve their times, although this is supposedly taken into account. Bolt’s Berlin record of 9.58s benefitted from a modest 0.9m/s tailwind. If he were to benefit from a maximum permissible tailwind of 2m/s, he would expend less effort on beating wind drag and reduce this record further by 0.05s to 9.48s.

Thirdly, running at altitude reduces the air density in the wind drag calculation, as was witnessed at the 1968 Olympic Games in Mexico City (2240m above sea level), where significant improvements over short distances were displayed (although for longer distances the altitude makes running more difficult). As a result, athletics world records are only permitted at altitudes of up to 1000m, but this still allows Bolt to reduce his time by a further 0.03s to 9.45s if he runs at this altitude.

“With the relatively big chunks we’ve seen Bolt take out of world records, we are still a long way from understanding the limits of his, and others’, sprinting speeds,” said Professor Barrow. “What this study serves to illustrate is the insight maths can give into sports performance, which has not been done previously to such a degree of accuracy.”

via How Usain Bolt can run faster — effortlessly.

Memory declines faster in years closest to death

Two new studies published in the April 4 online issue of Neurology, the medical journal of the American Academy of Neurology, suggest that a person’s memory declines at a faster rate in the last two-and-a-half years of life than at any other time after memory problems first begin. The second study shows that keeping mentally fit through board games or reading may be the best way to preserve memory during late life. Both studies were conducted by researchers at Rush University Medical Center.

“In our first study, we used the end of life as a reference point for research on memory decline rather than birth or the start of the study,” said study author Robert S. Wilson, PhD, study author and neuropsychologist at Rush University Medical Center in Chicago.

For the study, 174 Catholic priests, nuns and monks without memory problems had their memory tested yearly for six to 15 years before death. After death, scientists examined their brains for hallmarks of Alzheimer’s disease called plaques and tangles.

The study found that at an average of about two-and-a-half years before death, different memory and thinking abilities tended to decline together at rates that were 8 to 17 times faster than before this terminal period. Higher levels of plaques and tangles were linked to an earlier onset of this terminal period but not to rate of memory decline during it.

The second study, also conducted by Wilson, showed that keeping mentally fit through board games or reading may be the best way to preserve memory during late life.

The study, which focused on mental activities, involved 1,076 people with an average age of 80 who were free of dementia. Participants underwent yearly memory exams for about five years. They reported how often they read the newspaper, wrote letters, visited a library and played board games such as chess or checkers. Frequency of these mental activities was rated on a scale of one to five, one meaning once a year or less and five representing every day or almost every day.

“The results suggest a cause and effect relationship: that being mentally active leads to better cognitive health in old age,” said Wilson.

The results showed that people’s participation in mentally stimulating activities and their mental functioning declined at similar rates over the years. The researchers also found that they could predict participants’ level of cognitive functioning by looking at their level of mental activity the year before but that level of cognitive functioning did not predict later mental activity.

via Memory declines faster in years closest to death.

If their eyes are failing and their hearing is gone, non-children’s books with very large type are available at the library and these make great gifts for your grandparents who are beyond the age where they can do much else but read and move occasionally from room to room.

Defying conventional wisdom, water can float on oil

Defying thousands of years of conventional wisdom, scientists are reporting that it is possible for water to float on oil, a discovery they say has important potential applications in cleaning up oil spills that threaten seashores and fisheries. Their report appears in ACS’ journal Langmuir.

Chi M. Phan and colleagues point out that the ancient Greek philosopher Aristotle made an early attempt to explain flotation around 350 B.C. Today, most people know that less dense liquids float on more dense liquids. So crude oil with a density of about 58 pounds per cubic foot floats on sea water, which has a density of 64 pounds per cubic foot — and not vice-versa. Correct? Phan’s team decided to test that notion with computer models and in the lab.

They report that in certain cases, the conventional wisdom is wrong. By adding tiny amounts of water to a floating droplet of oil, they found that the ability of water drops to float at the surface of an oil bath depends on both the size of the droplet and the type of oil. Commercial vegetable oil has enough surface tension – the force between liquid molecules that allows beads of water to form or insects to walk on water — at its interfaces with air and water to support a droplet’s weight, while pure mineral oils do not. At the same time, they found that vegetable oil could not support drops bigger than about one one hundredth of a cubic inch. The authors suggest the new knowledge could help clean up oil spills, where water-borne, oil-eating microbes will mix more easily into the oil if suspended in the tiny droplets they describe. “This result can lead to a new and advanced mechanism in processing oil/water mixtures, such as biodegrading process of unwanted oils, including vegetable oils, sand oil tailings and oil spillages,” the authors said.

Click here to view a video of their experiment.

via Defying conventional wisdom, water can float on oil.

Our ancestors used fire a million years ago

When did our ancestors first use fire? That’s been a long-running debate, and now a new study concludes the earliest firm evidence comes from about 1 million years ago in a South African cave.

The ash and burnt bone samples found there suggest fires frequently burned in that spot, researchers said Monday.

Over the years, some experts have cited evidence of fire from as long as 1.5 million years ago, and some have argued it was used even earlier, a key step toward evolution of a larger brain. It’s a tricky issue. Even if you find evidence of an ancient blaze, how do you know it wasn’t just a wildfire?

The new research makes “a pretty strong case” for the site in South Africa’s Wonderwerk Cave, said Francesco Berna of Boston University, who presents the work with colleagues in the Proceedings of the National Academy of Sciences.

One expert said the new finding should be considered together with a previous discovery nearby, of about the same age. Burnt bones also have been found in the Swartkrans cave, not far from the new site, and the combination makes a stronger case than either one alone, said Anne Skinner of Williams College in Williamstown, Mass., who was not involved in the new study.

Another expert unconnected with the work, Wil Roebroeks of Leiden University in The Netherlands, said by email that while the new research does not provide “rock solid” evidence, it suggests our ancestors probably did use fire there at that time.

The ancestors probably brought burning material from natural blazes into the cave to establish the fires, said Michael Chazan of the University of Toronto, a study author. Stone tools at the site suggest the ancestors were Homo erectus, a species known from as early as about 2 million years ago.

The scientists didn’t find signs of fire preparation, like a hearth or a deep pit. But Berna said it’s unlikely the fires were simply natural blazes, such as from lightning strikes.

That’s because the evidence shows repeated fires burned deep inside the cave, he said. The cave entrance is almost 100 feet away, and because of changes in the cave over the past 1 million years, the entrance was apparently even farther away when the fires burned, he said. In contrast, he said, the bones at Swartkrans could have been burned by a natural fire in the open before winding up in that cave.

The scientists also found no sign that the Wonderwerk cave fires were ignited by spontaneous combustion of bat guano, which they called a rare but documented event.

Berna and colleagues describe animal bones that show discoloring and a chemical signature of being heated. They also report microscopic bits of ash in excavated dirt from the cave, indicating burning of light material like leaves, grasses and twigs. And they found evidence of heating in samples of fractured stone.

Several lines of evidence suggest the material was heated within the cave rather than blown or washed in from outside.

It’s not clear what the fires were used for. While the burnt bones suggest cooking, the ancestors might have eaten the meat raw and tossed the bones into the fire, Berna noted. Other possible uses might be warmth, light and protection from wild animals, he said. …

via Our ancestors used fire a million years ago – Phenomenica.

Mom hit by lightning: ‘I could feel my legs on fire’

For the Deas family of Florida, a little stroll to the Toys “R” Us became an ordeal they will never forget.

“At first I thought it was a car bomb. I mean, that’s the way it felt. I’m like, am I in Iraq or something?” Donna Deas said. “When I grabbed the baby and I’m coming out of the truck, (there was) a big explosion. And I could feel my legs on fire.”

The lightning struck a tree in the Hialeah, Fla., parking lot on March 15, just a few feet from where Deas and her family were standing. Donna was able to lay baby Haley in the truck just in time, before she and her husband James felt the shock, knocking them both out.

“My husband fell on the ground. I’m telling him, ‘Don’t move, don’t move. Just wait, just wait,’” Donna Deas recalled.

She said her legs were completely paralyzed for 20 to 30 minutes after the strike. But fortunately her baby was inside the truck and not a few feet away, she said.

“Thank God that baby didn’t make it to that stroller or she would have been zapped,” she said, pointing at it.

Florida is known as the lightning capital of the United States, with more than 500 people injured by lightning each year.

“It wasn’t raining or lightning and thundering,” Deas said. “It was just overcast and it was just bam, it was like in a split second.”

Lightning can strike up to 10 miles away from the actual storm, even where it’s not raining.

“I know one thing,” Deas said. “When it’s raining outside, I’m staying home.”

The National Weather Service says that if you find yourself outside in a thunderstorm, get inside a safe building or vehicle as fast as possible.

It says a safe building is one that is fully enclosed and has plumbing or wiring. Once inside, stay away from showers, sinks and bathtubs, as well as televisions, computers and other electronic equipment.

A safe vehicle “is any full enclosed metal-topped vehicle” such as a car, minivan, bus or truck with a hard top. When inside, do not use electronic devices such as the radio during a storm.

Do not take shelter under trees, and stay inside until 30 minutes after you hear the last thunder. …

via U.S. News – Mom hit by lightning: ‘I could feel my legs on fire’.