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How the First Stars in the Universe Came into Existence How the first stars formed from this dust and gas has been a burning question for years, but a state-of-the- art computer simulation now offers the most detailed picture yet of how these first stars in the universe came into existence, researchers say. The composition of the early universe was quite different from that of today, and the physics that governed the early universe were also somewhat simpler. Dr. Naoki Yoshida and colleagues in Japan and the U.S. incorporated these conditions of the early universe, sometimes referred to as the "cosmic dark ages, " to simulate the formation of an astronomical object that would eventually shine its light into this darkness. The result is a detailed description of the formation of a protostar-the early stage of a massive primordial star of our universe, and the researchers’ computer simulation, which has been called a "cosmic Rosetta Stone." sets the bar for further investigation into the star formation process. The question of how the first stars evolved is so important because their formations and eventual explosions provided the seeds for subsequent stars to come into being. According to their simulation, gravity acted on minute density variations in matter, gases, and the mysterious "dark matter" of the universe after the Big Bang in order to form this early stage of a star-a protostar with a mass of just one percent of our sun. The simulation reveals how pre-stellar gases would have actually evolved under the simpler physics of the early universe to form this protostar. Dr. Yoshida’s simulation also shows that the protostar would likely evolve into a massive star capable of synthesizing heavy elements, not just in later generations of stars, but soon after the Big Bang. "This geneal picture of star formation, and the ability to compare how stellar objects form in different time periods and regions of the universe, will eventually allow investigation into the originsof life and planets, " said Lars Hernquist, a Professor of Astronomy at Harvard University and a coauthor of this latest report. "The abundance of elements in the universe has increased as stars have accumulated, " he says, "and the formation and destruction of stars continues to spread these elements further across the universe. So when you think about it, all of the elements in our bodies originally formed from nuclear reactions in the centers of stars, long ago." Their simulation of the birth of a protostar in the early universe signifies a key step toward the ambitious goal of piecing together the formation of an entire primordial star and of predicting the mass and properties of these first stars of the universe. More powerful computers, more physical data, and an even larger range will be needed for further calculations and simulations, but these researchers hope to eventually extend this simulation to the point of nuclear reaction initiation--when a stellar object becomes a true star. "Dr. Yoshida has taken the study of primordial star formation to a new level with this simulation, but it still gets us only to the halfway point towards our final goal. It is like laying the foundation of a skyscraper, " said Volker Bromm, Assistant Professor of Astronomy at the University of Texas, Austin and the author of a companion article. "We must continue our studies in this area to understand how the initially tiny protostar grows, layer by layer, to eventually form a massive star. Buthere, the physics become much more complicated and even more computational resources are needed." According to the last paragraph, all of the following are goals of the simulation project EXCEPT ______.
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Students Learn Better with Touchscreen Desks Observe the criticisms of nearly any major public education system in the world, and a few of the many complaints are more or less universal. Technology moves faster than the education system. Teachers must teach at the pace of the slowest student rather than the fastest. And—particularly in the United States—grade school children as a group don’t care much for, or excel at, mathematics. So it’s heartening to learn that a new kind of "classroom of the future" shows promise at mitigating some of these problems, starting with that fundamental piece of classroom furniture: the desk. AUK study involving roughly 400 students, mostly aged 8-10 years, and a new generation of multi- touch, multi-user, computerized desktop surfaces is showing that over the last three years the technology has appreciably boosted students’ math skills compared to peers learning the same material via the conventional paper-and-pencil method. How Through collaboration, mostly, as well as by giving teachers better tools by which to micromanage individual students who need some extra instruction while allowing the rest of the class to continue moving forward. Science, Clay Dillow, classroom of the future, education, engineering, math, mathematics, Synergy Net Traditional instruction still shows respectable efficacy at increasing students fluency in mathematics, essentially through memorization and practice—dull, repetitive practice. But the researchers have concluded that these new touch screen desks boost both fluency and flexibility—the critical thinking skills that allow students to solve complex problems not simply through knowing formulas and devices, but by being able to figure out what there all problem is and the most effective means of stripping it down and solving it. One reason for this, the researchers say, is the multi-touch aspect of the technology. Students working in the next-gen classroom can work together at the same tabletop, each of them contributing and engaging with the problem as part of a group. Known as Synergy Net, the software uses computer vision systems that see in the infrared spectrum to distinguish between different touches on different parts of the surface, allowing students to access and use tools on the screen, move objects and visual aids around on their desktops, and otherwise physically interact with the numbers and information on their screens. By using these screens collaboratively, the researchers say, the students are to some extent teaching themselves as those with a stronger grasp on difficult concepts pull other students forward along with them. How does the new tech work to improve student’s mathematical learning
How the First Stars in the Universe Came into Existence How the first stars formed from this dust and gas has been a burning question for years, but a state-of-the- art computer simulation now offers the most detailed picture yet of how these first stars in the universe came into existence, researchers say. The composition of the early universe was quite different from that of today, and the physics that governed the early universe were also somewhat simpler. Dr. Naoki Yoshida and colleagues in Japan and the U.S. incorporated these conditions of the early universe, sometimes referred to as the "cosmic dark ages, " to simulate the formation of an astronomical object that would eventually shine its light into this darkness. The result is a detailed description of the formation of a protostar-the early stage of a massive primordial star of our universe, and the researchers’ computer simulation, which has been called a "cosmic Rosetta Stone." sets the bar for further investigation into the star formation process. The question of how the first stars evolved is so important because their formations and eventual explosions provided the seeds for subsequent stars to come into being. According to their simulation, gravity acted on minute density variations in matter, gases, and the mysterious "dark matter" of the universe after the Big Bang in order to form this early stage of a star-a protostar with a mass of just one percent of our sun. The simulation reveals how pre-stellar gases would have actually evolved under the simpler physics of the early universe to form this protostar. Dr. Yoshida’s simulation also shows that the protostar would likely evolve into a massive star capable of synthesizing heavy elements, not just in later generations of stars, but soon after the Big Bang. "This geneal picture of star formation, and the ability to compare how stellar objects form in different time periods and regions of the universe, will eventually allow investigation into the originsof life and planets, " said Lars Hernquist, a Professor of Astronomy at Harvard University and a coauthor of this latest report. "The abundance of elements in the universe has increased as stars have accumulated, " he says, "and the formation and destruction of stars continues to spread these elements further across the universe. So when you think about it, all of the elements in our bodies originally formed from nuclear reactions in the centers of stars, long ago." Their simulation of the birth of a protostar in the early universe signifies a key step toward the ambitious goal of piecing together the formation of an entire primordial star and of predicting the mass and properties of these first stars of the universe. More powerful computers, more physical data, and an even larger range will be needed for further calculations and simulations, but these researchers hope to eventually extend this simulation to the point of nuclear reaction initiation--when a stellar object becomes a true star. "Dr. Yoshida has taken the study of primordial star formation to a new level with this simulation, but it still gets us only to the halfway point towards our final goal. It is like laying the foundation of a skyscraper, " said Volker Bromm, Assistant Professor of Astronomy at the University of Texas, Austin and the author of a companion article. "We must continue our studies in this area to understand how the initially tiny protostar grows, layer by layer, to eventually form a massive star. Buthere, the physics become much more complicated and even more computational resources are needed." According to paragraph 4, what is NOT true about a protostar
Download Knowledge Directly to Your Brain For the first time, researchers have been able to hack into the process of learning in the brain, using induced brain patterns to create a learned behavior. It’s not quite as advanced as an instant kung-fu download, and it’s not as sleek as cognitive inception, but it’s still an important finding that could lead to new teaching and rehabilitation techniques. Future therapies could decode the brain activity patterns of an athlete or a musician, and use them as a benchmark for teaching another person a new activity, according to the researchers. Scientists from Boston University and ATR Computational Neuroscience Laboratories in Kyoto used functional magnetic resonance imaging, or fMRI, to study the learning process. They were examining the adult brain’s aptitude for visual perceptual learning, or VPL, in which repetitive training improves a person’s performance on a particular task. Whether adults can do this as well as young people has been an ongoing debate in neuroscience. Led by BU neuroscientist Takeo Watanabe, researchers used a method called decoded fMRI neurofeedback to stimulate the visual cortex. First they showed participants circles at different orientations. Then they used fMRI to watch the participants’ brain activity. The researchers were then able to train the participants to recreate this visual cortex activity. The volunteers were again placed in MRI machines and asked to visualize shapes of certain colors. The participants were asked to "somehow regulate activity in the posterior part of the brain" to make a solid green disc as large as they could. They were told they would get a paid bonus proportional to the size of this disc, but they weren’t told anything about what the disc meant. The researchers watched the participants’ brain activity and monitored the activation patterns in their visual cortices. "Participants can be trained to control the overall mean activation of an entire brain region, " the study authors write, "or the activation in one region relative to that in another region. " This worked even when test subjects were not aware of what they were learning, the researchers said. "The most surprising thing in this study is that mere inductions of neural activation patterns corresponding to a specific visual feature led to visual performance improvement on the visual feature, without presenting the feature or subjects’ awareness of what was to be learned, " Watanabe said in a statement. Watanabe and colleagues said this method can be a powerful tool. "It can ’incept’ a person to acquire new learning, skills, or memory, or possibly to restore skills or knowledge that has been damaged through accident, disease, or aging, without a person’s awareness of what is learned or memorized, " they Write. Who are most likely to benefit from the study
Download Knowledge Directly to Your Brain For the first time, researchers have been able to hack into the process of learning in the brain, using induced brain patterns to create a learned behavior. It’s not quite as advanced as an instant kung-fu download, and it’s not as sleek as cognitive inception, but it’s still an important finding that could lead to new teaching and rehabilitation techniques. Future therapies could decode the brain activity patterns of an athlete or a musician, and use them as a benchmark for teaching another person a new activity, according to the researchers. Scientists from Boston University and ATR Computational Neuroscience Laboratories in Kyoto used functional magnetic resonance imaging, or fMRI, to study the learning process. They were examining the adult brain’s aptitude for visual perceptual learning, or VPL, in which repetitive training improves a person’s performance on a particular task. Whether adults can do this as well as young people has been an ongoing debate in neuroscience. Led by BU neuroscientist Takeo Watanabe, researchers used a method called decoded fMRI neurofeedback to stimulate the visual cortex. First they showed participants circles at different orientations. Then they used fMRI to watch the participants’ brain activity. The researchers were then able to train the participants to recreate this visual cortex activity. The volunteers were again placed in MRI machines and asked to visualize shapes of certain colors. The participants were asked to "somehow regulate activity in the posterior part of the brain" to make a solid green disc as large as they could. They were told they would get a paid bonus proportional to the size of this disc, but they weren’t told anything about what the disc meant. The researchers watched the participants’ brain activity and monitored the activation patterns in their visual cortices. "Participants can be trained to control the overall mean activation of an entire brain region, " the study authors write, "or the activation in one region relative to that in another region. " This worked even when test subjects were not aware of what they were learning, the researchers said. "The most surprising thing in this study is that mere inductions of neural activation patterns corresponding to a specific visual feature led to visual performance improvement on the visual feature, without presenting the feature or subjects’ awareness of what was to be learned, " Watanabe said in a statement. Watanabe and colleagues said this method can be a powerful tool. "It can ’incept’ a person to acquire new learning, skills, or memory, or possibly to restore skills or knowledge that has been damaged through accident, disease, or aging, without a person’s awareness of what is learned or memorized, " they Write. What helps a person to do a particular task better in visual perceptual learning
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