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I plan on using this as a forum to post news articles that are primarily Science related News.
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Radio Waves 'See' Through Walls
http://www.sciencedaily.com/releases/2009/10/091012084217.htm
ScienceDaily (Oct. 12, 2009) — University of Utah engineers showed that a wireless network of radio transmitters can track people moving behind solid walls. The system could help police, firefighters and others nab intruders, and rescue hostages, fire victims and elderly people who fall in their homes. It also might help retail marketing and border control.
"By showing the locations of people within a building during hostage situations, fires or other emergencies, radio tomography can help law enforcement and emergency responders to know where they should focus their attention," Joey Wilson and Neal Patwari wrote in one of two new studies of the method.
Their method uses radio tomographic imaging (RTI), which can "see," locate and track moving people or objects in an area surrounded by inexpensive radio transceivers that send and receive signals. People don't need to wear radio-transmitting ID tags.
The study involved placing a wireless network of 28 inexpensive radio transceivers – called nodes – around a square-shaped portion of the atrium and a similar part of the lawn. In the atrium, each side of the square was almost 14 feet long and had eight nodes spaced 2 feet apart. On the lawn, the square was about 21 feet on each side and nodes were 3 feet apart. The transceivers were placed on 4-foot-tall stands made of plastic pipe so they would make measurements at human torso level.
Radio signal strengths between all nodes were measured as a person walked in each area. Processed radio signal strength data were displayed on a computer screen, producing a bird's-eye-view, blob-like image of the person.
A second study detailed a test of an improved method that allows "tracking through walls." That study has been placed on arXiv.org, an online archive for preprints of scientific papers. The study details how variations in radio signal strength within a wireless network of 34 nodes allowed tracking of moving people behind a brick wall.
The method was tested around an addition to Patwari's Salt Lake City home. Variations in radio waves were measured as Wilson walked around inside. The system successfully tracked Wilson's location to within 3 feet.
Wilson demonstrated radio tomographic imaging during a mobile communication conference last year, and won the MobiCom 2008 Student Research Demo Competition. The researchers now have a patent pending on the method.
"I have aspirations to commercialize this," says Wilson, who has founded a spinoff company named Xandem Technology LLC in Salt Lake City.
The research was funded by the National Science Foundation.
How It Works
Radio tomographic imaging (RTI) is different and much less expensive than radar, in which radar or radio signals are bounced off targets and the returning echoes or reflections provide the target's location and speed. RTI instead measures "shadows" in radio waves created when they pass through a moving person or object.
RTI measures radio signal strengths on numerous paths as the radio waves pass through a person or other target. In that sense, it is quite similar to medical CT (computerized tomographic) scanning, which uses X-rays to make pictures of the human body, and seismic imaging, in which waves from earthquakes or explosions are used to look for oil, minerals and rock structures underground. In each method, measurements of the radio waves, X-rays or seismic waves are made along many different paths through the target, and those measurements are used to construct a computer image.
In their indoor, outdoor and through-the-wall experiments, Wilson and Patwari obtained radio signal strength measurements from all the transceivers – first when the rectangle was empty and then when a person walked through it. They developed math formulas and used them in a computer program to convert weaker or "attenuated" signals – which occur when someone creates "shadows" by walking through the radio signals – into a blob-like, bird's-eye-view image of that person walking.
RTI has advantages. "RF [radio frequency] signals can travel through obstructions such as walls, trees and smoke, while optical and infrared imaging systems cannot," the engineers wrote. "RF imaging will also work in the dark, where video cameras will fail."
Even "where video cameras could work, privacy concerns may prevent their deployment," Wilson and Patwari wrote. "An RTI system provides current images of the location of people and their movements, but cannot be used to identify a person."
Would bombardment by radio waves pose a hazard? Wilson says the devices "transmit radio waves at powers 500 times less than a typical cell phone."
"And you don't hold it against your head," Patwari adds.
The technique cannot distinguish good guys from bad guys, but at least will tell emergency personnel where people are located, he adds.
Wilson believes radio imaging also could be used in "a smarter alarm system. … What if you put radios in your home [built into walls or plugged into outlets] and used tomography to locate people in your home. Not only would your security system be triggered by an intrusion, but you could track the intruder online or over your phone."
Radio tomography even might be used to study where people spend time in stores.
"Does a certain marketing display get people to stop or does it not?" Wilson asks. "I'm thinking of retail stores or grocery stores. They spend a lot of money to determine, 'Where should we put the cereal, where should we put the milk, where should we put the bread?' If I can offer that information using radio tomographic imaging, it's a big deal."
He says radio tracking also might be a relatively inexpensive method of border security, and would work in dark and fog unlike cameras.
Another possible use: automatic control of lighting, heating and air conditioning in buildings, says Wilson. Radio tracking might even control sound systems so that the best sound is aimed where people are located, as well as noise cancellation systems which could be aimed automatically at noise sources, Patwari says.
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Essay
The Collider, the Particle and a Theory About Fate
http://www.nytimes.com/2009/10/13/science/space/13lhc.html?_r=1&ref=science
By DENNIS OVERBYE
Published: October 12, 2009
More than a year after an explosion of sparks, soot and frigid helium shut it down, the world’s biggest and most expensive physics experiment, known as the Large Hadron Collider, is poised to start up again. In December, if all goes well, protons will start smashing together in an underground racetrack outside Geneva in a search for forces and particles that reigned during the first trillionth of a second of the Big Bang.
Then it will be time to test one of the most bizarre and revolutionary theories in science. I’m not talking about extra dimensions of space-time, dark matter or even black holes that eat the Earth. No, I’m talking about the notion that the troubled collider is being sabotaged by its own future. A pair of otherwise distinguished physicists have suggested that the hypothesized Higgs boson, which physicists hope to produce with the collider, might be so abhorrent to nature that its creation would ripple backward through time and stop the collider before it could make one, like a time traveler who goes back in time to kill his grandfather.
According to the so-called Standard Model that rules almost all physics, the Higgs is responsible for imbuing other elementary particles with mass.
“It must be our prediction that all Higgs producing machines shall have bad luck,” Dr. Nielsen said in an e-mail message. In an unpublished essay, Dr. Nielson said of the theory, “Well, one could even almost say that we have a model for God.” It is their guess, he went on, “that He rather hates Higgs particles, and attempts to avoid them.”
This malign influence from the future, they argue, could explain why the United States Superconducting Supercollider, also designed to find the Higgs, was canceled in 1993 after billions of dollars had already been spent, an event so unlikely that Dr. Nielsen calls it an “anti-miracle.”
Dr. Nielsen and Dr. Ninomiya started laying out their case for doom in the spring of 2008. It was later that fall, of course, after the CERN collider was turned on, that a connection between two magnets vaporized, shutting down the collider for more than a year.
Dr. Nielsen called that “a funny thing that could make us to believe in the theory of ours.”
He agreed that skepticism would be in order. After all, most big science projects, including the Hubble Space Telescope, have gone through a period of seeming jinxed. At CERN, the beat goes on: Last weekend the French police arrested a particle physicist who works on one of the collider experiments, on suspicion of conspiracy with a North African wing of Al Qaeda.
Dr. Nielsen and Dr. Ninomiya have proposed a kind of test: that CERN engage in a game of chance, a “card-drawing” exercise using perhaps a random-number generator, in order to discern bad luck from the future. If the outcome was sufficiently unlikely, say drawing the one spade in a deck with 100 million hearts, the machine would either not run at all, or only at low energies unlikely to find the Higgs.
Sure, it’s crazy, and CERN should not and is not about to mortgage its investment to a coin toss. The theory was greeted on some blogs with comparisons to Harry Potter. But craziness has a fine history in a physics that talks routinely about cats being dead and alive at the same time and about anti-gravity puffing out the universe.
As Niels Bohr, Dr. Nielsen’s late countryman and one of the founders of quantum theory, once told a colleague: “We are all agreed that your theory is crazy. The question that divides us is whether it is crazy enough to have a chance of being correct.”
Another of Dr. Nielsen’s projects is an effort to show how the universe as we know it, with all its apparent regularity, could arise from pure randomness, a subject he calls “random dynamics.”
We always assume that the past influences the future. But that is not necessarily true in the physics of Newton or Einstein. According to physicists, all you really need to know, mathematically, to describe what happens to an apple or the 100 billion galaxies of the universe over all time are the laws that describe how things change and a statement of where things start. The latter are the so-called boundary conditions — the apple five feet over your head, or the Big Bang.
The equations work just as well, Dr. Nielsen and others point out, if the boundary conditions specify a condition in the future (the apple on your head) instead of in the past, as long as the fundamental laws of physics are reversible, which most physicists believe they are.
“For those of us who believe in physics,” Einstein once wrote to a friend, “this separation between past, present and future is only an illusion.”
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Scientists Remove Amyloid Plaques From Brains Of Live Animals With Alzheimer's Disease
http://www.sciencedaily.com/releases/2009/10/091015091602.htm
ScienceDaily (Oct. 16, 2009) — A breakthrough discovery by scientists from the Mayo Clinic in Jacksonville, FL, may lead to a new treatment for Alzheimer's Disease that actually removes amyloid plaques — considered a hallmark of the disease — from patients' brains.
Das and colleagues made this unexpected discovery when they initially set out to prove that the activation of microgila trigger inflammation, making the disease worse. Their hypothesis was that microglia would attempt to remove the plaques, but would be unable to do so, and in the process cause excessive inflammation. To the surprise of the researchers, when microglia were activated by IL-6, they cleared the plaques from the brains.
To do this, the researchers over-expressed IL-6 in the brains of newborn mice that had yet to develop any amyloid plaques, as well in mice with pre-existing plaques. Using somatic brain transgenesis technology, scientists analyzed the effect of IL-6 on brain neuro-inflammation and plaque deposition. In both groups of mice, the presence of IL-6 lead to the clearance of amyloid plaques from the brain. Researchers then set out to determine exactly how IL-6 worked to clear the plaques and discovered that the inflammation induced by IL-6 directed the microglia to express proteins that removed the plaques. This research suggests that manipulating the brain's own immune cells through inflammatory mediators could lead to new therapeutic approaches for the treatment of neurodegenerative diseases, particularly Alzheimer's disease.
"This model is as close to human pathology as animal models get. These results give us an exciting lead to newer, more effective treatments of Alzheimer's disease," said Gerald Weissmann, M.D., Editor-in-Chief of The FASEB Journal. "This study demonstrates that investment in experimental biology is the best way to approach the challenge posed by an aging population to the cost of health care."
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Is Unknown Force In Universe Acting On Dark Matter?
http://www.sciencedaily.com/releases/2009/10/091022154644.htm#
ScienceDaily (Oct. 23, 2009) — An international team of astronomers have found an unexpected link between mysterious 'dark matter' and the visible stars and gas in galaxies that could revolutionise our current understanding of gravity.
One of the astronomers, Dr Hongsheng Zhao of the SUPA Centre of Gravity, University of St. Andrews, suggests that an unknown force is acting on dark matter. The findings are published this week in the scientific journal Nature.
Only 4% of the universe is made of known material. Stars and gas in galaxies move so fast that astronomers have speculated that the gravity from a hypothetical invisible halo of dark matter is needed to keep galaxies together. However, a solid understanding of dark matter as well as direct evidence of its existence has remained elusive.
Now the team believes that the interactions between dark and ordinary matter could be more important and more complex than previously thought, and even speculate that dark matter might not exist and that the anomalous motions of stars in galaxies are due to a modification of gravity on extragalactic scales.
Dr. Benoit Famaey (Universities of Bonn and Strasbourg) explains: "The dark matter seems to 'know' how the visible matter is distributed. They seem to conspire with each other such that the gravity of the visible matter at the characteristic radius of the dark halo is always the same. This is extremely surprising since one would rather expect the balance between visible and dark matter to strongly depend on the individual history of each galaxy."
Dr. Zhao at the SUPA Centre of Gravity notes, "The pattern that the data reveal is extremely odd. It's like finding a zoo of animals of all ages and sizes miraculously having identical, say, weight in their backbones or something. It is possible that a non-gravitational fifth force is ruling the dark matter with an invisible hand, leaving the same fingerprints on all galaxies, irrespective of their ages, shapes and sizes."
Such a force might solve an even bigger mystery, known as 'dark energy', which is ruling the accelerated expansion of the Universe. A more radical solution is a revision of the laws of gravity first developed by Isaac Newton in 1687 and refined by Albert Einstein's theory of General Relativity in 1916. Einstein never fully decided whether his equation should add an omnipresent constant source, now called dark energy.
Dr Famaey added, "If we account for our observations with a modified law of gravity, it makes perfect sense to replace the effective action of hypothetical dark matter with a force closely related to the distribution of visible matter."
The implications of the new research could change some of the most widely held scientific theories about the history and expansion of the universe.
Lead researcher Dr. Gianfranco Gentile at the University of Ghent concludes, "Understanding this puzzling conspiracy is probably the key to unlock the formation of galaxies and their structures."
--------------------------------------------------------------------------------
Journal reference:
Gianfranco Gentile, Benoit Famaey, HongSheng Zhao, Paolo Salucci. Universality of galactic surface densities within one dark halo scale-length. Nature, 2009; 461 (7264): 627 DOI: 10.1038/nature08437
Adapted from materials provided by University of St. Andrews.
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One Shot Of Gene Therapy, And Children With Congenital Blindness Can Now See
http://www.sciencedaily.com/releases/2009/10/091025091144.htm
ScienceDaily (Oct. 26, 2009) — Born with a retinal disease that made him legally blind, and would eventually leave him totally sightless, the nine-year-old boy used to sit in the back of the classroom, relying on the large print on an electronic screen and assisted by teacher aides. Now, after a single injection of genes that produce light-sensitive pigments in the back of his eye, he sits in front with classmates and participates in class without extra help. In the playground, he joins his classmates in playing his first game of softball.
The study, conducted by researchers from the University of Pennsylvania School of Medicine and the Center for Cellular and Molecular Therapeutics at The Children's Hospital of Philadelphia, used gene therapy to safely improve vision in five children and seven adults with Leber's congenital amaurosis (LCA). The greatest improvements occurred in the children, all of whom are now able to navigate a low-light obstacle course -- one result that the researchers call "spectacular."
Although the patients did not attain normal eyesight, half of them (six of 12) improved enough that they may no longer be classified as legally blind. "The clinical benefits have persisted for nearly two years since the first subjects were treated with injections of therapeutic genes into their retinas," said senior author Jean Bennett, M.D., Ph.D., F.M. Kirby professor of Ophthalmology at the University of Pennsylvania School of Medicine
"Children who were treated with gene therapy are now able to walk and play just like any normally sighted child," said co-first author Albert M. Maguire, M.D., an associate professor of Ophthalmology at Penn and a physician at Children's Hospital. "They can also carry out classroom activities without visual aids."
Walking along a dimly lit, simulated street route, the children were able to negotiate barriers they bumped into before the surgery. Another child, who since birth, could only see light and shadows, stared into his father's face and said he could see the color of his eyes. Later they played soccer together.
The 12 subjects ranged in age from 8 to 44 years old at the time of treatment. Four of the children, aged 8 to 11, are the world's youngest individuals to receive gene therapy for a non-lethal disease (A fifth subject was 17 years old). On the other end of the age scale, the 35-year-old man and 44-year-old woman are the oldest patients to ever receive gene therapy for retinal degeneration.
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Laws of Physics Vary Throughout the Universe, New Study Suggests
http://www.sciencedaily.com/releases/2010/09/100909004112.htm
A team of astrophysicists based in Australia and England has uncovered evidence that the laws of physics are different in different parts of the universe.
The report describes how one of the supposed fundamental constants of Nature appears not to be constant after all. Instead, this 'magic number' known as the fine-structure constant -- 'alpha' for short -- appears to vary throughout the universe.
"After measuring alpha in around 300 distant galaxies, a consistency emerged: this magic number, which tells us the strength of electromagnetism, is not the same everywhere as it is here on Earth, and seems to vary continuously along a preferred axis through the universe," Professor John Webb from the University of New South Wales said.
"The implications for our current understanding of science are profound. If the laws of physics turn out to be merely 'local by-laws', it might be that whilst our observable part of the universe favours the existence of life and human beings, other far more distant regions may exist where different laws preclude the formation of life, at least as we know it."
"If our results are correct, clearly we shall need new physical theories to satisfactorily describe them."
"It's one of the biggest questions of modern science -- are the laws of physics the same everywhere in the universe and throughout its entire history? We're determined to answer this burning question one way or the other."
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Key Mechanism Behind Sleep Discovered: Finding Holds Promise for Treatment of Fatigue and Sleep Disorders
http://www.sciencedaily.com/releases/2010/09/100914100302.htm
Washington State University researchers have discovered the mechanism by which the brain switches from a wakeful to a sleeping state. The finding clears the way for a suite of discoveries, from sleeping aids to treatments for stroke and other brain injuries.
"We know that brain activity is linked to sleep, but we've never known how," said James Krueger, WSU neuroscientist and lead author of a paper in the latest Journal of Applied Physiology. "This gives us a mechanism to link brain activity to sleep. This has not been done before."
The mechanism -- a cascade of chemical transmitters and proteins -- opens the door to a more detailed understanding of the sleep process and possible targets for drugs and therapies aimed at the costly, debilitating and dangerous problems of fatigue and sleeplessness. Sleep disorders affect between 50 and 70 million Americans, according to the Institute of Medicine of the National Academies. The Institute also estimates the lost productivity and mishaps of fatigue cost businesses roughly $150 billion, while motor vehicle accidents involving tired drivers cost at least $48 billion a year.
Even before the dawn of science, people have known that wakeful activity, from working to thinking to worrying, affects the sleep that follows. Research has also shown that, when an animal is active and awake, regulatory substances build up in the brain that induce sleep.
"But no one ever asked before: What is it in wakefulness that is driving these sleep regulatory substances?" said Krueger. "No one ever asked what it is that's initiating these sleep mechanisms. People have simply not asked the question."
The finding reinforces a view developed by Krueger and his colleagues that sleep is a "local phenomenon, that bits and pieces of the brain sleep" depending on how they've been used.
The link between sleep, brain cell activity and ATP has many practical consequences, Krueger said.
For example:
>>>The study provides a new set of targets for potential medications. Drugs designed to interact with the receptors ATP binds to may prove useful as sleeping pills.
>>>Sleep disorders like insomnia can be viewed as being caused by some parts of the brain being awake while other parts are asleep, giving rise to new therapies.
>>>ATP-related blood flow observed in brain-imaging studies can be linked to activity and sleep.
>>>Researchers can develop strategies by which specific brain cell circuits are oriented to specific tasks, slowing fatigue by allowing the used parts of the brain to sleep while one goes about other business. It may also clear the way for stroke victims to put undamaged regions of their brains to better use.
>>>Brain cells cultured outside the body can be used to study brain cell network oscillations between sleep-like and wake-like states, speeding the progress of brain studies.
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Early Lung Cancer Detection: Optical Technology Shows Potential for Prescreening Patients
at High Risk
http://www.sciencedaily.com/releases/2010/10/101005171040.htm
ScienceDaily (Oct. 9, 2010) — Researchers from Northwestern University and NorthShore University HealthSystem (NorthShore) have developed a method to detect early signs of lung cancer by examining cheek cells in humans using pioneering biophotonics technology.
Early detection is critical for improving cancer survival rates. Yet, one of the deadliest cancers in the United States, lung cancer, is notoriously difficult to detect in its early stages. Now, researchers have developed a method to detect lung cancer by merely shining diffuse light on cells swabbed from patients' cheeks.
The optical technique is called partial wave spectroscopic (PWS) microscopy and was developed by Vadim Backman, professor of biomedical engineering at Northwestern's McCormick School of Engineering and Applied Science. Backman and Roy earlier used PWS to assess the risk of colon and pancreatic cancers, also with promising results.
PWS can detect cell features as small as 20 nanometers, uncovering differences in cells that appear normal using standard microscopy techniques. The PWS-based test makes use of the "field effect," a biological phenomenon in which cells located some distance from the malignant or pre-malignant tumor undergo molecular and other changes.
"Despite the fact that these cells appear to be normal using standard microscopy, which images micron-scale cell architecture, there are actually profound changes in the nanoscale architecture of the cell," Backman said. "PWS measures the disorder strength of the nanoscale organization of the cell, which we have determined to be one of the earliest signs of carcinogenesis and a strong marker for the presence of cancer in the organ."
"PWS is a paradigm shift, in that we don't need to examine the tumor itself to determine the presence of cancer," added Hariharan Subramanian, a research associate in Backman's lab who played a central role in the development of the technology.
A further assessment of the performance characteristics of the "disorder strength" (as a biomarker) showed greater than 80 percent accuracy in discriminating cancer patients from individuals in the three control groups.
"The results are similar to other successful cancer screening techniques, such as the pap smear," Backman said. "Our goal is to develop a technique that can improve the detection of other cancers in order to provide early treatments, much as the pap smear has drastically improved survival rates for cervical cancer."
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Robotic Gripper Runs on Coffee ... and Balloons
http://www.sciencedaily.com/releases/2010/10/101025161140.htm
ScienceDaily (Oct. 25, 2010) — The human hand is an amazing machine that can pick up, move and place objects easily, but for a robot, this "gripping" mechanism is a vexing challenge. Opting for simple elegance, researchers from Cornell University, University of Chicago and iRobot have bypassed traditional designs based around the human hand and fingers, and created a versatile gripper using everyday ground coffee and a latex party balloon.
Here's how it works: An everyday party balloon filled with ground coffee -- any variety will do -- is attached to a robotic arm. The coffee-filled balloon presses down and deforms around the desired object, and then a vacuum sucks the air out of the balloon, solidifying its grip. When the vacuum is released, the balloon becomes soft again, and the gripper lets go.
"The ground coffee grains are like lots of small gears," Lipson said. "When they are not pressed together they can roll over each other and flow. When they are pressed together just a little bit, the teeth interlock, and they become solid."
As for the right particulate material, anything that can jam will do in principle, and early prototypes involved rice, couscous and even ground- up tires. They settled on coffee because it's light but also jams well, Amend said. Sand did better on jamming but was prohibitively heavy. What sets the jamming-based gripper apart is its good performance with almost any object, including a raw egg or a coin -- both notoriously difficult for traditional robotic grippers.
The project was supported by the Defense Advanced Research Projects Agency.
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