The common view that nerves transmit impulses through electricity is wrong and they really transmit sound, according to a team of Danish scientists.
The Copenhagen University researchers argue that biology and medical textbooks that say nerves relay electrical impulses from the brain to the rest of the body are incorrect.
Science & Technology
Before reading this column, please make a note of what its subject will be. If you answer correctly it will be of special interest to some people at Princeton University.
The subject is things we cannot explain, such as extrasensory perception (ESP) and paranormal events. Such matters have been studied at a Princeton laboratory since 1979, but the laboratory will close at the end of February.
Robert G. Jahn, 76, who founded Princeton Engineering Anomalies Research (PEAR), has his own explanation of why the laboratory is being closed:
"For 28 years we have done what we wanted to do," Jahn told the New York Times. "If people don't believe us after all the results we've produced, they never will."
The subject is things we cannot explain, such as extrasensory perception (ESP) and paranormal events. Such matters have been studied at a Princeton laboratory since 1979, but the laboratory will close at the end of February.
Robert G. Jahn, 76, who founded Princeton Engineering Anomalies Research (PEAR), has his own explanation of why the laboratory is being closed:
"For 28 years we have done what we wanted to do," Jahn told the New York Times. "If people don't believe us after all the results we've produced, they never will."
© REUTERS/ESA/Handout
This map shows the topography of the south polar region of Mars, including topography buried by thick deposits of icy material.
This map shows the topography of the south polar region of Mars, including topography buried by thick deposits of icy material.
The scientists used a joint NASA-Italian Space Agency radar instrument on the European Space Agency Mars Express spacecraft to gauge the thickness and volume of ice deposits at the Martian south pole covering an area larger than Texas.
The deposits, up to 2.3 miles thick, are under a polar cap of white frozen carbon dioxide and water, and appear to be composed of at least 90 percent frozen water, with dust mixed in, according to findings published in the journal Science.
In January, James Randi secured a mystery item in a specially designated locker in his Florida office, and challenged clairvoyants everywhere to use their remote viewing skills to divine its nature and claim a million dollar prize. The contents were "devined" by a pair of cryptographers.
There is enough water frozen at Mars' south pole to cover the entire planet to a depth of about 11 metres, new data collected by the Mars Express orbiter suggests.
The new estimate comes from measurements made by a radar instrument that can see through layers of ice to the bottom of the polar cap, about 3.7 kilometres down.
The new estimate comes from measurements made by a radar instrument that can see through layers of ice to the bottom of the polar cap, about 3.7 kilometres down.
Never before has so much news been within reach of li'l ol' you, tucked away there behind your keyboard. In an instant, you can be connected with news organizations the world over, soaking up the latest about the French presidential elections, or the price of tea in China. So how come you know so little of what's going on out there in the big, bad world?
Don't get huffy about it. You know what I'm talking about.
Don't get huffy about it. You know what I'm talking about.
If the plan to replace incandescent light bulbs takes hold, the phaseout could save enough energy to eliminate the need to build 80 of the 150 or so coal-fired power plants now planned nationwide, it is estimated.
Physicists in France are the first to watch single photons appear spontaneously, live a brief life, and then vanish into thin air. The experiment is the best realization so far of "quantum non-demolition" (QND) measurements on single photons, whereby the presence of a photon is determined without destroying it. As well as providing an elegant demonstration of quantum mechanics, the researchers also believe that the technique could be exploited in quantum information systems.
Detecting a photon usually involves absorbing the photon - and ultimately destroying it - in a photodetector. However, it is sometimes possible to make a measurement in a much gentler manner, leaving the system in more or less the same state as was measured. Such QND measurements have become commonplace for large systems like atoms - which can be probed gently using photons. But photons are much more delicate than atoms, which makes QND very difficult.
Detecting a photon usually involves absorbing the photon - and ultimately destroying it - in a photodetector. However, it is sometimes possible to make a measurement in a much gentler manner, leaving the system in more or less the same state as was measured. Such QND measurements have become commonplace for large systems like atoms - which can be probed gently using photons. But photons are much more delicate than atoms, which makes QND very difficult.
A rogue ball of ice as big as Pennsylvania smashes into an Alaska-sized dwarf planet, spewing debris across the solar system and furnishing the planet with two new moons. Although it could be a disaster scene from a sci-fi movie, the event actually took place in the outer realms of our solar system a few billion years ago. "It's just a spectacular story," says planetary scientist Michael Brown of the California Institute of Technology in Pasadena, whose team has discovered the fragments of the cosmic catastrophe. What's more, the find sheds new light on the early history of our solar system.
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| ©NASA/ESA/HST |
| Computer model of 2003 EL61 and its two moons. |
The comet that killed the dinosaurs opened the evolutionary door for one of Earth's most diverse groups of creatures: mammals. David Archibald, Ph.D., a professor of evolutionary biology at San Diego State, has made this transition from dinosaurs to mammals his expertise.
Archibald studies early mammalian fossils and is trying to constrain the origins of the phylum to which humans belong. His research has taken him around the world in search of the remains of terrestrial creatures.
Archibald studies early mammalian fossils and is trying to constrain the origins of the phylum to which humans belong. His research has taken him around the world in search of the remains of terrestrial creatures.
Comment: From the actual paper:
"On the action potential as a propagating density pulse and the role of anesthetics"
Authors: Thomas Heimburg, Andrew D. Jackson
Subj-class: Biological Physics; Medical Physics
The Hodgkin-Huxley model of nerve pulse propagation relies on ion currents through specific resistors called ion channels. We discuss a number of classical thermodynamic findings on nerves that are not contained in this classical theory. Particularly striking is the finding of reversible heat changes, thickness and phase changes of the membrane during the action potential.
Data on various nerves rather suggest that a reversible density pulse accompanies the action potential of nerves.
Here, we attempted to explain these phenomena by propagating solitons that depend on the presence of cooperative phase transitions in the nerve membrane. These transitions are, however, strongly influenced by the presence of anesthetics. Therefore, the thermodynamic theory of nerve pulses suggests a explanation for the famous Meyer-Overton rule that states that the critical anesthetic dose is linearly related to the solubility of the drug in the membranes. "
That is "density pulse", which for the public has been translated as "sound", "accompanies the action potential" rather than replaces it.
A density pulse is the movement of a fluid.