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Earliest Stage Of Planet Formation In Our Solar System Dated ScienceDaily (Dec. 20, 2007) UC Davis researchers have dated the earliest step in the formation of the solar system -- when microscopic interstellar dust coalesced into mountain-sized chunks of rock -- to 4,568 million years ago, within a range of about 2,080,000 years. UC Davis postdoctoral researcher Frederic Moynier, Qing-zhu Yin, assistant professor of geology, and graduate student Benjamin Jacobsen established the dates by analyzing a particular type of meteorite, called a carbonaceous chondrite, which represents the oldest material left over from the formation of the solar system. The physics and timing of this first stage of planet formation are not well understood, Yin said. So, putting time constraints on the process should help guide the physical models that could be used to explain it. In the second stage, mountain-sized masses grew quickly into about 20 Mars-sized planets and, in the third and final stage, these small planets smashed into each other in a series of giant collisions that left the planets we know today. The dates of those stages are well established. Carbonaceous chondrites are made up of globules of silica and grains of metals embedded in black, organic-rich matrix of interstellar dust. The matrix is relatively rich in the element manganese, and the globules are rich in chromium. Looking at a number of different meteorites collected on Earth, the researchers found a straight-line relationship between the ratio of the amount of manganese to that of chromium, the amount of matrix in the meteorites, and the amount of chromium-53. These meteorites never became large enough to heat up from radioactive decay, so they have never been melted, Yin said. They are "cosmic sediments," he said. By measuring the amount of chromium-53, Yin said, they could work out how much of the radioactive isotope manganese-53 had initially been present, giving an indication of age. They then compared the amount of manganese-53 to slightly younger igneous (molten) meteorites of known age, called angrites. The UC Davis researchers estimate the timing of the formation of the carbonaceous chondrites at 4,568 million years ago, ranging from 910,000 years before that date to 1,170,000 years later. "We've captured a moment in history when this material got packed together," Yin said. The work is published in the Dec. 20 issue of Astrophysical Journal Letters, and was funded by grants from NASA. http://www.sciencedaily.com/releases/2007/12/071219130308.htm Stephen Rouse Biology P.7 About 4,568 million years ago was when our solar system was formed, according to UC Davis researchers, first publishing their findings in the Dec. 20 issue of Astrophysical Journal Letters. Frederic Moynier, Qing-zhu Yin, and Benjamin Jacobsen analyzed particular type of meteorites, called carbonaceous chondrite which is the oldest material on the earth. Before our planets were formed 20 mountains approximately the size of mars were present. In a collision between those mountains it created our solar system. The researches looked at carbonaceous chondrites which are metals and interstellar dust. They studied and compared different meteorites they found on earth and looked at the amount of chromium-53. They were able to figure out how much radioactive isotope manganese-53 there had been in the beginning and therefore determining the age of the rock. This article first caught my eye because I had always thought that scientists had no idea how long ago the solar system was created. It amazed me to see how many years the solar system has actually been around and makes me wonder how other things were created, such as how humans developed, water, and so on. If we keep the progress we are making in discovering how the universe was created, we might actually find exactly how old our UNIVERSE is. Hopefully when my kids and their kids are alive they will know exactly how everything was created. Hot Spot On Saturn's Tiny Moon Enceladus Causes Icy Plumes ScienceDaily (Dec. 20, 2007) Enceladus, the tiny satellite of Saturn, is colder than ice, but data gathered by the Cassini-Huygens Mission to Saturn and Titan has detected a hot spot that could mean there is life in the old moon after all. In fact, for researchers of the outer planets, Enceladus is so intellectually hot, it's smokin'. The heat being generated on the moon's south pole at a hot spot is enough to eject plumes of ice and vapor above Enceladus. These plumes, according to William B. McKinnon, Ph.D., professor of earth and planetary sciences in Arts & Sciences at Washington University in St. Louis, are this moon's most intriguing feature. "The plume particles are like smoke, ice smoke," McKinnon said. "If you were standing on Enceladus' surface you wouldn't even be able to see the plumes. The particles are just larger than the wavelength of light, about one-thousandths of a millimeter. Most icy bodies of this size are geologically inert, but this is a clear indication of geological activity. Cassini has found active venting of water vapor. This leads to scientifically intriguing speculations and questions." One is: Is this active ice volcanism on Enceladus? If so, is it due to ice sublimating, in the manner of a comet, or to a different mechanism, like boiling water, as in Old Faithful at Yellowstone? The biggest question: If there is water on Enceladus, is there life? "I don't think so," McKinnon said. "The strongest piece of evidence against that is measurements made from Earth of the plume don't show any sodium. If the source of the plumes were fresh water like on Earth, the plumes would contain enough detectable sodium. Fresh water flows through rocks and on streambeds, and so it picks up bits of mineral chemistry. The emerging view is that there's not obvious evidence for a subterranean ocean in contact with rock, no boiling or venting." McKinnon said that the leading model for the cause of the plumes on Enceladus is that the moon's tides cause its crust to ratchet or rub back and forth in a set of faults near the south pole. This action generates just enough heat to vaporize the ice that makes the plumes. Cassini, which has been passing through the plumes of Enceladus, makes its next pass in March of 2008. It will go deeper into the plume and take more pictures of the moon's features, the venting area in the infrared, impact craters, cracks and fissures, and make better measurements of gases and vapors. McKinnon presented "Cold Fire: The Geology and Geophysics of Enceladus," Dec. 10, 2007, at the Fall Meeting of the American Geophysical Union in San Francisco. The mythological Enceladus is buried beneath Mount Etna and is responsible for the mountain's tremors and volcanism. The moon Enceladus is only 500 kilometers wide roughly 300 miles wide, the distance between St. Louis and Chicago, and quite round for such a small body. Data from Cassini has revealed a rock-rich body, 55 to 60 percent rock by mass, with a surface of nearly pure water ice. The temperature at the poles is some -220 degrees Celsius (C), but the hot spot is at least 100 degrees warmer. Enceladus is in a special relationship called dynamical resonance with another one of Saturn's moons, Dione. Every time Dione, in an exterior orbit around Saturn, circles Saturn, Enceladus goes around exactly twice. This resonance keeps Enceladus' orbit tidally pumped, maintaining an eccentric path that leads to a continuous squeezing under Saturn's gravity field. This process makes a small part of the planet hot, relatively, for an icy satellite. It's the same mechanism that runs the tremendously hot silicate volcanism of Io and activates Europa, maintaining its ocean. Lo and Europa are two of Jupiter's moons. "You only have to get so hot to make ice active," McKinnon said. "It doesn't have to get tremendously hot like it does on Lo. Ice volcanism requires an order of magnitude less energy for things to work out pretty well. The hot spots are -100 degrees C or possibly 'warmer'; the area around it is more than twice as cold. We still can't say how truly 'hot' the hot spots are. We'll probably learn this in March." Adapted from materials provided by Washington University in St. Louis. http://www.sciencedaily.com/releases/2007/12/071217155253.htm Tommy Stormberg The question that people have pondered over for years: Are there such things as aliens and is there life somewhere other than Earth? Enceladus is a satellite that is by Saturn. Data has been found by the Cassini-Huygens Mission that there is a hotspot on the moon that is very uncharacteristic. Fumes of ice have been detected coming from the moon and it just might as well mean boiling water. These fumes are tiny. McKinnon relates it to being just larger than the wavelength of light, which obviously means that humans cannot see it. Though there is a chance that life is on there McKinnon says that he highly doubts it. Sodium was not found in the ice and he can conclude that there was now real water erosion against any type of rocks to pick up any minerals. The satellite is scheduled in March of 2008 to make another pass of the moon and take pictures of the moon to closer study it. Based on the opinion of McKinnon I dont think there is life on that moon. I never have believed in aliens and probably never will, but if they make a discovery then I might just change my mind. This could possibly be a scientific breakthrough that would change everybodys perspective. I would be extremely surprised and awestruck if they find life on the moon but Im not getting my hopes up. Humans may never find any life on other planets. Does Time Slow In Crisis? No, Say Researchers ScienceDaily (Dec. 19, 2007) In The Matrix, hero Neo wins his battles when time slows in the simulated world. In the real world, accident victims often report a similar slowing as they slide unavoidably into disaster. But can humans really experience events in slow motion? Apparently not, said researchers at Baylor College of Medicine in Houston, who studied how volunteers experience time when they free-fall 100 feet into a net below. Even though participants remembered their own falls as having taken one-third longer than those of the other study participants, they were not able to see more events in time. Instead, the longer duration was a trick of their memory, not an actual slow-motion experience. "People commonly report that time seemed to move in slow motion during a car accident," said Dr. David Eagleman, assistant professor of neuroscience and psychiatry and behavioral sciences at BCM. "Does the experience of slow motion really happen, or does it only seem to have happened in retrospect? The answer is critical for understanding how time is represented in the brain." When roller coasters and other scary amusement park rides did not cause enough fear to make "time slow down," Eagleman and his graduate students Chess Stetson and Matthew Fiesta sought out something even more frightening. They hit upon Suspended Catch Air Device diving, a controlled free-fall system in which "divers" are dropped backwards off a platform 150 feet up and land safely in a net. Divers are not attached to ropes and reach 70 miles per hour during the three-second fall. "It's the scariest thing I have ever done," said Eagleman. "I knew it was perfectly safe, and I also knew that it would be the perfect way to make people feel as though an event took much longer than it actually did." The experiment consisted of two parts. In one, the researchers asked participants to reproduce with a stopwatch how long it took someone else to fall, and then how long their own fall seemed to have lasted. In general, people estimated that their own fall appeared 36 percent longer than that of their compatriots. However, to determine whether that distortion meant they could actually see more events happening in time -- like a camera in slow motion -- Eagleman and his students developed a special device called the perceptual chronometer that was strapped to the volunteers' wrists. Numbers flickered on the screen of the watch-like unit. The scientists adjusted the speed at which the numbers flickered until it was too fast for the divers to see. They theorized that if time perception really slowed, the flickering numbers would appear slow enough for the divers to easily read while in free-fall. They found that while the subjects were able to read numbers presented at normal speeds during the free-fall, they could not read them at faster-than-normal speeds. "We discovered that people are not like Neo in The Matrix, dodging bullets in slow-mo. The paradox is that it seemed to participants as though their fall took a long time. The answer to the paradox is that time estimation and memory are intertwined: the volunteers merely thought the fall took a longer time in retrospect," he said. During a frightening event, a brain area called the amygdala becomes more active, laying down a secondary set of memories that go along with those normally taken care of by other parts of the brain. "In this way, frightening events are associated with richer and denser memories. And the more memory you have of an event, the longer you believe it took," Eagleman explained. The study allowed them to deduce that a person's perception of time is not a single phenomenon that speeds or slows. "Your brain is not like a video camera," said Eagleman. Eagleman and his team have been able to verify this conclusion in the laboratory. In an experiment that appeared in a recent issue of PLoS One, Eagleman and graduate student Vani Pariyadath used 'oddballs' in a sequence to bring about a similar duration distortion. For example, when they flashed on the computer screen a shoe, a shoe, a shoe, a flower and a shoe, viewers believed the flower stayed on the screen longer, even though it remained there the same amount of time as the shoes. Pariyadath and Eagleman showed that even though durations are distorted during the oddball, other aspects of time -- such as flickering lights or accompanying sounds -- do not change. The conclusion from both studies was the same. "It can seem as though an event has taken an unusually long time, but it doesn't mean your immediate experience of time actually expands. It simply means that when you look back on it, you believe it to have taken longer," Eagleman said. "This is related to the phenomenon that time seems to speed up as you grow older. When you're a child, you lay down rich memories for all your experiences; when your older, you've seen it all before and lay down fewer memories. Therefore, when a child looks back at the end of a summer, it seems to have lasted forever; adults think it zoomed by." The study appeared online recently in the journal Public Library of Science One. Funding for this research came from the National Institutes of Health. Adapted from materials provided by Baylor College of Medicine. http://www.sciencedaily.com/releases/2007/12/071211233934.htm Stephen Rouse Biology P.7 When I was in eighth grade I was helping my dad paint. I was about 8 feet up on the latter painting. When I reached over to get more paint on the brush my foot slipped and I fell that whole 8 feet and landed on my back. Even though it hurt extremely bad and I hurt for about a week I didnt get injured badly. When I look back on it, it seems like the fall took an unusually long amount of time. I was just waiting to hit the ground painfully. Scientists at Baylor College of Medicine in Houston conducted an experiment to test if your brain can actually do slow motion at times of crisis. What they did was had people get in a car that was going to jump of a ramp and into a net. Even though this was safe it was extremely scary. They tested if it actually was slow motion by flashing numbers of for the people to read and if they could read the ones that go fast they could conclude that the brain actually goes in slow motion. Their test results came back as expected: Your brain cannot go in slow-motion. This effect comes when you remember these events. Part of your brain called the amygdale becomes active and makes the memory more vivid and detailed creating the illusion that it lasted a long time. This article really fascinated me not only because I have experienced that before but the brain is one of the points I love studying. I hope to study how the brain functions more in my science classes. Supercomputers Offer New Explanation Of Tunguska Disaster ScienceDaily (Dec. 19, 2007) The stunning amount of forest devastation at Tunguska a century ago in Siberia may have been caused by an asteroid only a fraction as large as previously published estimates, Sandia National Laboratories supercomputer simulations suggest. The asteroid that caused the extensive damage was much smaller than we had thought, says Sandia principal investigator Mark Boslough of the impact that occurred June 30, 1908. That such a small object can do this kind of destruction suggests that smaller asteroids are something to consider. Their smaller size indicates such collisions are not as improbable as we had believed. Because smaller asteroids approach Earth statistically more frequently than larger ones, he says, We should be making more efforts at detecting the smaller ones than we have till now. The new simulation which more closely matches the widely known facts of destruction than earlier models shows that the center of mass of an asteroid exploding above the ground is transported downward at speeds faster than sound. It takes the form of a high-temperature jet of expanding gas called a fireball. This causes stronger blast waves and thermal radiation pulses at the surface than would be predicted by an explosion limited to the height at which the blast was initiated. Our understanding was oversimplified, says Boslough, We no longer have to make the same simplifying assumptions, because present-day supercomputers allow us to do things with high resolution in 3-D. Everything gets clearer as you look at things with more refined tools. The new interpretation also accounts for the fact that winds were amplified above ridgelines where trees tended to be blown down, and that the forest at the time of the explosion, according to foresters, was not healthy. Thus previous scientific estimates had overstated the devastation caused by the asteroid, since topographic and ecologic factors contributing to the result had not been taken into account. Theres actually less devastation than previously thought, says Boslough, but it was caused by a far smaller asteroid. Unfortunately, its not a complete wash in terms of the potential hazard, because there are more smaller asteroids than larger ones. Boslough and colleagues achieved fame more than a decade ago by accurately predicting that that the fireball caused by the intersection of the comet Shoemaker-Levy 9 with Jupiter would be observable from Earth. Simulations show that the material of an incoming asteroid is compressed by the increasing resistance of Earths atmosphere. As it penetrates deeper, the more and more resistant atmospheric wall causes it to explode as an airburst that precipitates the downward flow of heated gas. Because of the additional energy transported toward the surface by the fireball, what scientists had thought to be an explosion between 10 and 20 megatons was more likely only three to five megatons. The physical size of the asteroid, says Boslough, depends upon its speed and whether it is porous or nonporous, icy or waterless, and other material characteristics. Any strategy for defense or deflection should take into consideration this revised understanding of the mechanism of explosion, says Boslough. One of most prominent papers in estimating frequency of impact was published five years ago in Nature by Sandia researcher Dick Spalding and his colleagues, from satellite data on explosions in atmosphere. They can count those events and estimate frequencies of arrival through probabilistic arguments, says Boslough. The work was presented at the American Geophysical Union meeting in San Francisco on Dec. 11. A paper on the phenomenon, co-authored by Sandia researcher Dave Crawford and entitled Lowaltitude airbursts and the impact threat has been accepted for publication in the International Journal of Impact Engineering. The research was paid for by Sandias Laboratory-Directed Research and Development office. Adapted from materials provided by DOE/Sandia National Laboratories. http://www.sciencedaily.com/releases/2007/12/071218122415.htm Tommy Stormberg Biology P.7 In 1908 an asteroid hit Siberia and caused a massive amount of damage. Scientist first predicted that the asteroid was extremely massive, but super computers simulated the crash and discovered that the asteroid was only a fraction of what they had originally predicted. When asteroids hit the earth they travel at a speed that is faster than sound. The computers predict that high winds made the impact stronger than it would have been without them. When an asteroid is coming to earth it penetrates the earths atmosphere and creates a fireball. This may also be a factor in why it had been such a devastating blow to the earth. This shows that we need to be more prepared for if a meteor that we think is small ends up being big. I also think this is a very under minded subject. There are so many meteors out in the universe it would be hard to predict how many. We are all so worried about our nuclear threats and such, but we also need to be worried about natural disasters such as a meteor hitting the earth. If there is a decent sized rock going faster than the speed of sound straight to us, who knows how bad we could be hit. It could be the end of the world as we know it. Scientists are able now to predict if a meteor can come close to the earth now by studying explosions in the atmosphere. Hopefully, nothing catastrophic happens in the near future caused by these massive fire balls. New Nanowire Battery Holds 10 Times The Charge Of Existing Ones ScienceDaily (Dec. 20, 2007) Stanford researchers have found a way to use silicon nanowires to reinvent the rechargeable lithium-ion batteries that power laptops, iPods, video cameras, cell phones, and countless other devices. The new version, developed through research led by Yi Cui, assistant professor of materials science and engineering, produces 10 times the amount of electricity of existing lithium-ion, known as Li-ion, batteries. A laptop that now runs on battery for two hours could operate for 20 hours, a boon to ocean-hopping business travelers. "It's not a small improvement," Cui said. "It's a revolutionary development." The greatly expanded storage capacity could make Li-ion batteries attractive to electric car manufacturers. Cui suggested that they could also be used in homes or offices to store electricity generated by rooftop solar panels. "Given the mature infrastructure behind silicon, this new technology can be pushed to real life quickly," Cui said. The electrical storage capacity of a Li-ion battery is limited by how much lithium can be held in the battery's anode, which is typically made of carbon. Silicon has a much higher capacity than carbon, but also has a drawback. Silicon placed in a battery swells as it absorbs positively charged lithium atoms during charging, then shrinks during use (i.e., when playing your iPod) as the lithium is drawn out of the silicon. This expand/shrink cycle typically causes the silicon (often in the form of particles or a thin film) to pulverize, degrading the performance of the battery. Cui's battery gets around this problem with nanotechnology. The lithium is stored in a forest of tiny silicon nanowires, each with a diameter one-thousandth the thickness of a sheet of paper. The nanowires inflate four times their normal size as they soak up lithium. But, unlike other silicon shapes, they do not fracture. Research on silicon in batteries began three decades ago. Candace Chan, a graduate student of Cui, explained: "The people kind of gave up on it because the capacity wasn't high enough and the cycle life wasn't good enough. And it was just because of the shape they were using. It was just too big, and they couldn't undergo the volume changes." Then, along came silicon nanowires. "We just kind of put them together," Chan said. For their experiments, Chan grew the nanowires on a stainless steel substrate, providing an excellent electrical connection. "It was a fantastic moment when Candace told me it was working," Cui said. Cui said that a patent application has been filed. He is considering formation of a company or an agreement with a battery manufacturer. Manufacturing the nanowire batteries would require "one or two different steps, but the process can certainly be scaled up," he added. "It's a well understood process." The breakthrough is described in detail in a paper, "High-performance lithium battery anodes using silicon nanowires," published online Dec. 16 in Nature Nanotechnology, written by Cui, his graduate chemistry student Candace Chan and five others. Also contributing to the paper in Nature Nanotechnology were Halin Peng and Robert A. Huggins of Materials Science and Engineering at Stanford, Gao Liu of Lawrence Berkeley National Laboratory, and Kevin McIlwrath and Xiao Feng Zhang of the electron microscope division of Hitachi High Technologies in Pleasanton, Calif. Adapted from materials provided by Stanford University. http://www.sciencedaily.com/releases/2007/12/071219103105.htm Stephen Rouse Biology P.7 Some of the most successful advances in science is the development of computers. Computers have helped us do almost everything in our daily life. Entertainment is growing as a new way to take advantage of these amazing machines. Ipods and cell phones have been one of the biggest booming industries in the past 10 years. With these computers you need rechargeable batteries. Stanford researchers have developed a new rechargeable battery called high-performance lithium battery anodes using silicon nanowires. This new form of battery is so much more efficient that a battery that could originally hold 2 hours now can hold 20 hours. Nanotechnology is the reason these batteries are so good. Tiny silicon wires stores lithium and inflate four time their normal size to store it without damaging the battery. They did not take long to copywrite their new invention and are searching car companys to use it. Hybrid cars would use these batteries more than any type of machine. My opinion is that this is a great advancement in preserving gas. If this battery is used in Hybrid cars it may knock down the price and be acceptable for other peoples budget. With the rising prices of gas it might accually save you a fair amount of money by buying these cars. This discovery was published in the paper in Nature Nanotechnology. Traffic Jam Mystery Solved By Mathematicians ScienceDaily (Dec. 19, 2007) Mathematicians from the University of Exeter have solved the mystery of traffic jams by developing a model to show how major delays occur on our roads, with no apparent cause. Many traffic jams leave drivers baffled as they finally reach the end of a tail-back to find no visible cause for their delay. Now, a team of mathematicians from the Universities of Exeter, Bristol and Budapest, have found the answer and published their findings in the journal Proceedings of the Royal Society. The team developed a mathematical model to show the impact of unexpected events such as a lorry (tractor trailer) pulling out of its lane on a dual carriageway (divided highway with median between traffic going in opposite directions). Their model revealed that slowing down below a critical speed when reacting to such an event, a driver would force the car behind to slow down further and the next car back to reduce its speed further still. The result of this is that several miles back, cars would finally grind to a halt, with drivers oblivious to the reason for their delay. The model predicts that this is a very typical scenario on a busy highway (above 15 vehicles per km). The jam moves backwards through the traffic creating a so-called 'backward travelling wave', which drivers may encounter many miles upstream, several minutes after it was triggered. Dr Gbor Orosz of the University of Exeter said: "As many of us prepare to travel long distances to see family and friends over Christmas, we're likely to experience the frustration of getting stuck in a traffic jam that seems to have no cause. Our model shows that overreaction of a single driver can have enormous impact on the rest of the traffic, leading to massive delays." Drivers and policy-makers have not previously known why jams like this occur, though many have put it down to the sheer volume of traffic. While this clearly plays a part in this new theory, the main issue is around the smoothness of traffic flow. According to the model, heavy traffic will not automatically lead to congestion but can be smooth-flowing. This model takes into account the time-delay in drivers' reactions, which lead to drivers braking more heavily than would have been necessary had they identified and reacted to a problem ahead a second earlier. Dr Orosz continued: "When you tap your brake, the traffic may come to a full stand-still several miles behind you. It really matters how hard you brake - a slight braking from a driver who has identified a problem early will allow the traffic flow to remain smooth. Heavier braking, usually caused by a driver reacting late to a problem, can affect traffic flow for many miles." The research team now plans to develop a model for cars equipped with new electronic devices, which could cut down on over-braking as a result of slow reactions. Adapted from materials provided by University of Exeter. http://www.sciencedaily.com/releases/2007/12/071219103102.htm Tommy Stormberg Biology P.7 One of the things that I hate the most is traffic jams. Sometimes it seems to slow down to a complete crawl that goes on for miles, only to see that there was no apparent reason for the jam. Mathematicians from the University of Exeter have unlocked how they develop with no cause. They developed a model that showed a typical traffic schene and the normal ways humans drive such as hitting the brakes extremely hard when you are too close to a car. They way they have predicted it works is the cars go faster ahead and the farther you get to the back the slower you end up going. This is caused by traffic not traveling smoothly. For example is somebody slams one their brakes rather than tapping on them, it could cause a chain reaction causing the person behind you to go slower, and the person behind them to go slower, and the person behind them to go slower until you get to complete hault. This is another extremely important discovery in America. People will have more time to do their jobs and support a greater society. They are talking about creating an electronic devise that could cut down on hard breaking and reduce traffic jams. Because the Christmas season is coming up and people will be traveling long distances to meet their family it gives a new view on why it is so conjested and maybe will get people to drive more smoothly. 2-D Invisibility Cloak For Visible Light Created ScienceDaily (Dec. 19, 2007) Harry Potter may not have talked much about plasmonics in J. K. Rowling's fantasy series, but University of Maryland researchers are using this emerging technology to develop an invisibility cloak that exists beyond the world of bespectacled teenage wizards. A research team at Maryland's A. James Clark School of Engineering comprised of Professor Christopher Davis, Research Scientist Igor Smolyaninov, and graduate student Yu-Ju Hung, has used plasmon technology to create the world's first invisibility cloak for visible light. The engineers have applied the same technology to build a revolutionary superlens microscope that allows scientists to see details of previously undetectable nanoscale objects. Generally speaking, when we see an object, we see the visible light that strikes the object and is reflected. The Clark School team's invisibility cloak refracts (or bends) the light that strikes it, so that the light moves around and past the cloak, reflecting nothing, leaving the cloak and its contents "invisible." The invisibility cloak device is a two-dimensional pattern of concentric rings created in a thin, transparent acrylic plastic layer on a gold film. The plastic and gold each have different refractive properties. The structured plastic on gold in different areas of the cloak creates "negative refraction" effects, which bend plasmonselectron waves generated when light strikes a metallic surface under precise circumstancesaround the cloaked region. This manipulation causes the plasmon waves to appear to have moved in a straight line. In reality they have been guided around the cloak much as water in a stream flows around a rock, and released on the other side, concealing the cloak and the object inside from visible light. The invisibility that this phenomenon creates is not absolutely perfect because of energy loss in the gold film. The team achieved this invisibility under very specialized conditions. The researchers' cloak is just 10 micrometers in diameter; by comparison, a human hair is between 50 to 100 micrometers wide. Also, the cloak uses a limited range of the visible spectrum, in two dimensions. It would be a significant challenge to extend the cloak to three dimensions because researchers would need to control light waves both magnetically and electronically to steer them around the hidden object. The technology initially may work only for small objects of specific controlled shape. The team also has used plasmonics to develop superlens microscopy technology, which can be integrated into a conventional optical microscope to view nanoscale details of objects that were previously undetectable. The superlens microscope could one day image living cells, viruses, proteins, DNA molecules, and other samples, operating much like a point-and-shoot camera. This new technology could revolutionize the capability to view nanoscale objects at a crucial stage of their development. The team believes they can improve the resolution of their microscope images down to about 10 nanometersone ten thousandth of the width of a human hair. A large reason for the success of the group's innovations in both invisibility and microscopy is that surface plasmons have very short wave lengths, and can therefore move data around using much smaller-scale guiding structures than in existing devices. These small, rapid waves are generated at optical frequencies, and can transport large amounts of data. The group also has made use of the unique properties of metamaterials, artificially structured composites that help control electromagnetic waves in unusual ways using plasmonic phenomena. The diverse applications the group has derived from their plasmonics research is an example of the ingenuity of researchers approaching new and dynamic technologies that offer broad and unprecedented capabilities. The research has attracted a great deal of attention within the scientific community, industry and government agencies. Related plasmonics research offers applications for military and computer chip technologies, which could benefit from the higher frequencies and rapid data transfer rates that plasmons offer. The team's research has been funded by the National Science Foundation and Clark School Corporate Partner BAE Systems. Smolyaninov and Davis have published an article in the journal Science about their superlens microscope technology, titled "Magnifying Superlens in the Visible Frequency Range." The group and their colleagues from Purdue University will also soon publish a paper about their invisibility cloak research. Adapted from materials provided by University of Maryland. http://www.sciencedaily.com/releases/2007/12/071218192009.htm Stephen Rouse Biology P.7 When I first read this article I was amazed. Ever since I was a little kid I thought of how cool it would be to become invisible. After reading Harry Potter and learning about the cloak that Harry uses I wondered if somebody would accually make something similar to that. And long behold, they did. Not exactly with magic but with plasmonics. At James Clark School of Engineering researchers worked long and hard on this cloak that will most likely be used by the military. The way the cloak works is when the light hits the object it does not bounce back to your eyes but bends the light and reflects nothing. The plastic and gold inside the cloak have different refractive properties. It creates a negative refraction effect. An easier way to look at it is that the light sort of flows past the cloak like water on a rock. The downfall to this is that it is extremely small. It is about one-fifth of the thinkness of a human hair and cannot be used three demencionaly. This research was funded by the National Science Foundation and Clark School Corporate Partner BAE Systems and has caused a lot of talking in the scientific community. It is so extremely advanced that it opens new doors to creating the best that humans can offer. If they accually succeed in creating a full cloak who knows how far we could go with science, and who knows what is next? Carnivorous Argentine ants that have invaded coastal California devour other insects. When that food's gone, the ants become vegetarians. The amazingly adaptive behavior, detailed in what is the first study of this ant's diet, has allowed the invaders to spread successfully and rapidly. The tiny dark-brown and black critters, an invasive species originally from Argentina, have infested coastal communities and displaced native ant species, even though many of the locals are 10 times larger than the Argentinians. The new finding, based on an eight-year study of a population of ants in the foothills southeast of San Diego, reveals how the alien ants thrive so well in a foreign land. Their success is linked to their dietary versatility, according to results detailed in this week's online issue of the journal Proceedings of the National Academy of Sciences. "Despite the fact that these species are known to cause ecological problems in many countries, scientists really didnt know what they eat," said study leader David Holway of the University of California, San Diego. Holway and his colleagues discovered that when Argentine ants first move into an area they become fierce predators of native insects. But as the ants eliminate their competitors and thus, their main source of food, they switch from a carnivorous, protein-rich diet to a largely carbohydrate, sugar-water diet of honeydew nectar. "Honeydew nectar is essentially digested plant sap excreted by aphids and scales," Holway said. "If youve ever parked your car under a tree and found your windshield covered with sticky stuff, thats honeydew from aphids or scales." This ability to switch from an all-insect protein diet to a carbohydrate-rich one also allows the ants to expand their populations because plant material is much easier to find in irrigated residential communities, the researchers say. "By virtue of this great dietary flexibility, Argentine ants are able to consume a variety of sources of food, and its this ability to consume carbohydrates that contributes to their success," Holway said. The discovery of the ants preferred sugar snack also offers a way to help California residents control ant infestations in their homes. "If you cut down on watering to limit plant growth, Argentine ant numbers should decline," Holway said. 2007 LiveScience.com. All rights reserved. http://www.msnbc.msn.com/id/22314760/ Tommy Stormberg Biology P.7 In the world, animals must adapt to their surroundings to survive. If they do not then most likely they will die off and be the food for another species. Carnivorous Argentine ants are no exception. They invaded coastal California and devoured other insects. After they destroyed all the others they became vegetarians. An eight year study was conducted in southeast San Diego and showed how they do so well in a foreign land. Scientists conducted this experiment to find out exactly what these ants eat. "Despite the fact that these species are known to cause ecological problems in many countries, scientists really didnt know what they eat," said the leader of the study, David Holway at the University of California. The way the ants work is when they are introduced into a new area they get rid of their competitors and then feed on honeydew nectar. Despite how cool they are they are a great disturbance of the land. They have caused many problems in the process of Mother Nature and need to be stopped. Holway said that in order to decrease the population of these ants they need to limit plant growth, which is not an easy job. These ants really are fascinating. Some species take years to adapt to their surroundings but these little things about the size of a pea can adapt within a few days, making them an extremely popular species for scientists to study and learn from. I wonder though how the humans adapted to their surroundings and every other type of animal.

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