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Obtaining Drinking Water from Air Humidity Not a plant to be seen, the desert ground is too dry. But the air contains water, and research scientists have found a 1 of obtaining drinking water from air humidity. The system is based completely on renewable energy and is therefore autonomous. Cracks permeate the dried-out desert ground and the landscape bears testimony to the lack of water. But even here, where there are no lakes, rivers or groundwater, considerable quantities of water are stored in the air. In the Negev desert in Israel, for example, annual average relative air humidity is 64 percent-in every cubic meter of air there are 11.5 milliliters of water. German research scientists have found a way of converting this air humidity autonomously into drinkable water. "The process we have developed is based exclusively on renewable energy sources 2 thermal solar collectors and photovoltaic ceils, 3 makes this method completely energy-autonomous. It will 4 function in regions where there is no electrical infrastructure." says Siegfried Egner, head of the research team. The principle of the 5 is as follows: hygroscopic brine-saline solution which absorbs moistureruns down a tower-shaped unit and absorbs water from the air. It is then sucked 6 a tank a few meters off the ground in which a vacuum prevails. Energy from solar collectors 7 up the brine, which his diluted by the water it has 8 . Because of the vacuum, the boiling point of the liquid is lower than it would be under 9 atmospheric pressure. This effect is known from the mountains: as the atmospheric pressure there is lower than in the valley, water boils at temperatures distinctly below 100℃. The evaporated, non-saline water is condensed and runs down through a completely filled tube in a controlled manner. The gravity of this water column 10 produces the vacuum and so a vacuum pump is not needed. The reconcentrated brine 11 down the tower surface again to absorb moisture from the air. "The concept is suitable for various water 12 . Single-person units and plants supplying water to entire hotels are conceivable, " says Egner. Prototypes have been built for 13 system components-air moisture absorption and vacuum evaporation-and the research scientists have already 14 their interplay on a laboratory scale. In a further 15 the researchers intend to develop a demonstration facility.
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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 have researchers been able to do with the help of the study
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." What does the "astronomical object" in paragraph 2 refer to
Natural Gas 1. Natural gas is produced from reservoirs deep beneath the earth’s surface. It is a fossil fuel, meaning that it is derived from organic material buried in the earth millions of years ago. The main component of natural gas is methane. 2. The popularity and use of clean natural gas has increased dramatically over the past 50 years as pipeline infrastructure has been installed to deliver it conveniently and economically to millions of residential, commercial and industrial customers worldwide. Today, natural gas services available in all 50 states in the U.S., and is the leading energy choice for fueling American homes and industries. More than 65 million American homes use natural gas. In fact, natural gas is the most economical source for home energy needs, costing one-third as much as electricity. In addition to heating homes, much of the gas used in the United States is used as a raw material to manufacture a wide variety of products, from paint to fibers for clothing, to plastics for healthcare, computing and furnishings. Natural gas is also used in a significant number of new electricity-generating power plants. 3. Natural gas is one of the safest and cleanest fuels available. It emits less pollution than other fossil fuel sources. When natural gas is burned, it produces mostly carbon dioxide and water vapour—the same substances emitted when humans exhale. Compared with some other fossil fuels, natural gas emits the least amount of carbon dioxide into the air when combusted, making natural gas the cleanest burning fossil fuel of all. 4. The United States consumes about one-third of the world’s natural gas output, making it the largest gas-consuming region in the world. The U.S. Department of Energy Information Administration forecasts that natural gas demand will grow by more than 50 percent by 2025. 5. There are huge reserves of natural gas beneath the earth’s surface. The largest reserves of natural gas can be found in Russia, West and North Africa and the Middle East. LNG has been produced domestically and imported in the United States for more than four decades. Today, the leading imports of LNG are Japan, Korea, France and Spain. Paragraph 4 ______.
Europa’s Watery under World Europa, one of Jupiter’s 63 known moons, looks bright and icy on the surface. But appearances can be deceiving: Miles within its cracked, frigid shell, Europa probably hides giant pools of liquid water. Where scientists find liquid water, they hope to find life as well. Since we can’t go diving into Europa’s depths just yet, scientists instead have to investigate the moon’s surface for clues to what lies beneath. In a new study, scientists investigated one group of strange ice patterns on Europa and concluded that the formations mark the top of an underground pool that holds as much water as the U. S. Great Lakes. Pictures of Europa, which is slightly smaller than Earth’s moon, clearly show a tangled, icy mishmash of lines and cracks known as "chaos terrains." These chaotic places cover more than half of Europa. For more than 10 years, scientists have wondered what causes the formations. The new study suggests that they arise from the mixing of vast underground stores of liquid water with icy material near the surface. For scientists who suspect that Europa also may be hiding life beneath its icy surface, the news about the new lake is exciting. "It would be great if these lakes harbored life, " Britney Schmidt, a planetary scientist who worked on the study, told Science News. "But even if they didn’t, they say that Europa is doing something interesting and active right now. " Schmidt, a scientist at the University of Texas at Austin, and her colleagues wanted to know how chaos terrains form. Since they couldn’t rocket to Europa to see for themselves, they searched for similar formations here on Earth. They studied collapsed ice shelves in Antarctica and icy caps on volcanoes in Iceland. Those features on Earth formed when liquid water mixed with ice. The scientists now suspect something similar might be happening on Europa: that as water and ice of different temperatures mingle and shift, the surface fractures. This would explain the jumbled ice sculptures. "Fracturing catastrophically disrupts the ice in the same way that it causes ice shelves to collapse on Earth, " Schmidt told Science News. She and her team found that the process could be causing chaos terrains to form quickly on Europa. The new study suggests that on this moon, elements such as oxygen from the surface blend with the deep bodies of water. That mixture may create an environment that supports life. Schmidt and her colleagues are the first group of scientists studying Europa.
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