Complex, Active Fault Lines Created Devastating Haitian Earthquake
The Haitian earthquake that devastated the country and resulted in ever-growing death tolls was caused by an active tangle of tectonic faults in the Caribbean and North American crustal plates.
According to Jian Lin, a Woods Hole Oceanographic Institution scientist, the quake was “large, but not huge.” However, it caused so much damage because of three factors: First, the quake was centered only 10 miles southwest of Haiti’s capital, Port au Prince; second, the quake was shallow, about 10-15 km below the land; and third, the Haitian buildings were not built to withstand such force. This resulted in a worst-case scenario for the Haitian people, and Lin states that “it should be a wake-up call for the entire Caribbean.”
The quake occurred along a “strike-slip” fault, meaning that connecting plates were sliding in opposite directions. Adjacent faults can stay in place for years, with pressure mounting as each plate tries to move in the opposite direction. In this particular case, the Caribbean Plate was sliding east, and the Gonvave Platelet was sliding west. When enough pressure mounts between the two plates that are pushing against each other, one of them jerks forward, instantly relieving the pressure and resulting in massive amounts of energy that can spawn earthquakes and tsunamis. This same type of fault line exists along California’s San Andreas Fault.
Geologists say that aftershocks can be expected in the coming days, weeks, months, years and even decades. Since the stress has been relieved in that particular fault, Lin says that it should not experience another quake of this magnitude for perhaps 100 years.
However, the particular patch of faults that spawned the devastating Haitian earthquake is surrounded by more faults throughout the Caribbean, and those faults are definitely active.
Lin espouses a focus on earthquake education and a reconstruction of houses and buildings that can withstand earthquakes of that magnitude. “A lot of people forget [earthquakes] quickly and do not take the words of geologists seriously,” Lin states. “But if your house is close to an active fault, it is best that you do not forget where you live.”
To aid in Haitian relief efforts, please visit the Red Cross website for further information. Or play some games!
Source: Science Daily
Wet Computer Will Mimic Human Brain
The human brain is a fascinating and mysterious organ. Often compared to a computer, it is estimated to contain 100 billion neurons, each of which has 1,000 connections. Each connection fires about 200 times per second, and that’s on the low end. That’s about 20,000 trillion calculations per second. I’d like to see your Acer Aspire do that. Researchers have found, however, that while a circuit board may not be able to replicate the human brain, a “wet computer” can.
A wet computer replaces the inner workings of a typical computer with chemicals that mimic the processes and interactions of biological molecules, such as neurons. A team of researchers have been given a grant of 2.6 million dollars that they will use to hopefully create the world’s first wet computer. The point is not to create a computer that can run better, faster, stronger, than our current computers, but rather to create one that can be applied to completely new terrains.
“The type of wet information technology we are working towards will not find its near-term application in running business software,” explained University of Southhampton’s Klaus-Peter Zauner, a collaborator on the project. “But it will open up application domains where current IT does not offer any solutions – controlling muscular robots, fine-grained control of chemical assembly, and intelligent drugs that process the chemical signals of the human body and act according to the local biochemical state of the cell.”
In other words, the computer will be used to mimic natural body processes and apply that technology towards building a more advanced, human-like Cylon robot. At least, that’s what I’m hoping it will do.
The project will focus on studying how lipids work. Lipids are a type of macromolecule that makes up fats, waxes and steroids. They’re used in the creation of the lipid bilayer, a dually water-loving and water-hating polymer that surrounds cells. Proteins embedded in the bilayer allow certain molecules and enzymes in and out of the cell in a tightly-regulated screening process – much like the scanners you have to go through during airport security. When two cells bump into one another, the lipid walls come into contact and create a passage that allows molecules to pass from one cell to the other. These molecules act as signals that begin complicated chemical processes in the cell. The key part is that once these chemical processes begin, the cell begins a “refractory period,” a kind of hibernation where any further chemical signals cannot influence the current reaction. A neuron works in the same way – once information reaches a neuron, it uses its own energy to pass it along to other networks of neurons.
“Every neuron is like a molecular computers; ours is a very crude abstraction of what neurons do,” continues Dr. Zauner. “But the essence of neurons is the capability to get ‘excited;’ it can re-form an input signal and has its own energy supply so it can fire out a new signal.”
This certainly does sound promising, though I wonder how limited these chemical reactions will be. A computer is required to run thousands of commands a minute – could cellular reactions do the same if they’re essentially being shut down any time a new command requires a chemical reaction?
Source: BBC News
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Stingrays Use Tools
The term “tool usage” often implies the manipulation of the surrounding environment using an object of some kind. But when you have no opposable thumbs, prehensile forelimbs, or, for that matter, any limbs to speak of, the term is more loosely applied.
Take the common stingray. One would think that it was doomed to live a tool-less life, gazing longingly at those lucky sons of guns with their fancy dorsal fins and elongated snouts, all of which are useful in manipulating the oceanic environment. Fortunately for our cartilaginous compadres, they have evolved their own internal tool: they’ve learned to shoot jets of water in order to extract food hidden in pipes and other areas.
Stingrays are cartilaginous fish, a group that, according to Dr. Michael Kuba of Hebrew University, “have often been considered to be reflex machines having very acute senses but limited cognitive capabilities.” However, Dr. Kuba believes that stingrays are considered to be “reflex machines” partially because they are so difficult to study.
The study began while the researchers were observing the captive stingrays and found that they engaged in what the researchers initially believed were “play” activities: Whenever a human came around, they would squirt water out of the tank. Dr. Kuba says, “My interpretation is that small food remnants remained lodged in the duckweed, triggering the ‘water spouting behavior.’ Also, the rays appeared to have learned that humans mean ‘food’ and therefore began to spout water as soon as someone approached the aquarium.” Essentially, the stingrays had begun to use water spouting as a technique to dislodge food that may have been stuck in the duckweed of their tanks.
In further experiments, Dr. Kurba placed plastic pipes filled with hidden food to see how captive South American stingrays got the meal out of the container. Dr. Kuba and his team placed a plastic tube with one open end inside the tank. Inside the pipe was food, which the stingrays could get either by sucking at the open end, or blowing water through it to dislodge the food. In this case, the stingrays always sucked at the open end.
Additionally, they began to paint one side of the food tube white and the other side black. The stingrays can only get their meals at the “white” end. The results of this experiment will show whether stingrays can solve problems. They would actually have to think, and reason: “These tubes have two ends, but only one has food in it.”
Dr. Kuba believes that stingray research will reveal important aspects of the vertebrate thought process. “They are members of one of the oldest lines of vertebrates and to know more about their abilities will help us to learn more about the evolution of cognition in vertebrates.”
Source: BBC News
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Ancestors to Dinosaurs Breathed Like Birds
Though the dinosaurs succumbed to a well-placed meteorite, their ancestors managed to survive a similar mass extinction, and it may be because their lungs were bird-like. The Permian-Triassic extinction, deemed the “mother of all extinctions,” resulted in the eradication of 96 percent of sea life and 70 percent of land life. The cause of the extinction is unknown, though there appears to have been three separate phases: gradual environmental change, a catastrophic event, and the release of methane from the sea floor, which resulted in anoxia and a sea-level change. This led to hypoxia, which is a severe shortage of oxygen. Oxygen being a necessary component for breathing, as you might imagine that this became an issue for anything that wanted to live.
Well, not so for the archosaurs – ancestors to birds and alligators. Recent research has found that alligators breathe like birds. Mammals and other species breathe through their lungs – a dead-end chamber in which oxygen is processed and carbon dioxide is released. A bird’s lungs, however, are different. A breath of air takes a winding one-way street through the lungs, passing through multiple air sacs that store air. Since there is no mixing of oxygen-rich and oxygen-poor air, our avian amigos have a more efficient gas-exchange than mammals. Apparently, this is also how alligators breathe – minus the air sacs – and if their archosaur ancestors breathed this way as well, this may explain their lack of extinction.
“People incorrectly believe that you must have avian-style air sacs in order to have unidirectional flow,” states C.G. Farmer of the University of Utah, one of the co-authors of the study. “Alligators don’t have air sacs, so no one ever looked.”
Archosaurs evolved along two separate paths – one led to alligators and crocodiles, the other led to birds. It was previously believed that bird-like breathing evolved after the split, but because it’s been found that alligators have the same unidirectional breathing as birds, this study may mean that bird-breathing evolved earlier, before the split occurred. This may explain why archosaurs dominated the Triassic period, when the post-extinction ecosystem had oxygen levels as low as 12 percent, as compared to the 21 percent we enjoy today.
“The real importance of this air-flow discovery in gators is it may explain the turnover in fauna between the Permian and the Triassic, with the synapsids losing their dominance and being supplanted by these archosaurs,” said Farmer.
Source: Discover
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Lauren Admire thinks a wet computer means pouring water into the tower.
Published: Jan 18, 2010 10:00 pm