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What Is the Coolest Gas in the UniverseWhat is the coldest air temperature ever recorded on the Earth Where was this low temperature recorded The coldest recorded temperature on Earth was -91℃, which (51) in Antarctica in 1988.We encounter an interesting situation when we discuss temperatures in (52) . Temperatures in Earth orbit actually range from about 20℃ to 120℃. The temperature depends upon (53) you are in direct sunlight or shade. Obviously, -120℃ is colder than our body can safely endure. Thank NASA science for well-designed space (54) that protect astronauts from these temperature extremes.The space temperatures just discussed affect only our area of the solar (55) . Obviously, it is hotter closer to the Sun and colder as we travel away from the Sun. Astronomers estimate temperatures at Pluto are about -210℃. How cold is the lowest estimated temperature in the entire universe Again, it depends upon your (56) . We are taught it is supposedly (57) to have a temperature below absolute zero, which is -273℃, at which atoms do not move. Two scientists, whose names are Cornell and Wieman, have successfully cooled down a gas to a temperature barely (58) absolute zero. They won a Nobel Prize in Physics in 2001 for their work—not a discovery, in this case.Why is the two scientists work so important to scienceIn the 1920s, Satyendra Nath Bose was studying an interesting (59) about special light particles we now call photons. Bose had trouble (60) other scientists to believe his theory, (61) he contacted Albert Einstein. Einstein’s calculations helped him theorize that atoms (62) behave as Bose thought—but only at very cold temperatures.Scientists have also discovered that (63) atoms can help them make the world’s atomic docks even more accurate. These clocks are so accurate today they would only lose one second (64) six million years! Such accuracy will help us travel in space because distance is velocity times time (d=vt). With the long distances involved in space (65) , we need to know time as accurately as possible to get accurate distance. 51（）
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Researchers Discover Why Humans Began Walking UprightMost of us walk and carry items in our hands every day. These are seemingly simple activities that the majority of us don’t question. But an international team of researchers, including Dr. Richmond from GW’s Columbian College of Arts and Sciences, have discovered that human walking upright, may have originated millions of years ago as an adaptation to carrying scarce, high-quality resources. The team of researchers from the US, England, Japan and Portugal investigated the behavior of modern-day chimpanzees as they competed for food resources, in an effort to understand what ecological settings would lead a large ape—one that resembles the 6 million-year old ancestor we shared in common with living chimpanzees—to walk on two legs."These chimpanzees provide a model of the ecological conditions under which our earliest ancestors might have begun walking on two legs ", said Dr. Richmond.The research findings suggest that chimpanzees switch to moving on two limbs instead of four in situations where they need to monopolize a resource. Standing on two legs allows them to carry much more at one time because it frees up their hands. Over time, intense bursts of bipedal activity may have led to anatomical changes that in turn became the subject of natural selection where competition for food or other resources was strong.Two studies were conducted by the team in Guinea. The first study was conducted by the team in Kyoto University’s "outdoor laboratory" in a natural clearing in Bossou Forest. Researchers allowed the wild chimpanzees access to different combinations of two different types of nut—the oil palm nut, which is naturally widely available, and the coula nut, which is not. The chimpanzees’ behavior was monitored in three situations: (a) when only oil palm nuts were available, (b)when a small number of coula nuts were available, and(c) when coula nuts were the majority available resource.When the rare coula nuts were available only in small numbers, the chimpanzees transported more at one time. Similarly, when coula nuts were the majority resource, the chimpanzees ignored the oil palm nuts altogether. The chimpanzees regarded the coula nuts as a more highly-prized resource and competed for them more intensely.In such high-competition settings, the frequency of cases in which the chimpanzees started moving on two legs increased by a factor of four. Not only was it obvious that bipedal movement allowed them to carry more of this precious resource, but also that they were actively trying to move as much as they could in one go by using everything available—even their mouths.The second study, by Kimberley Hockings of Oxford Brookes University, was a 14- month study of Bossou chimpanzees crop-raiding, a situation in which they have to compete for rare and unpredictable resources. Here, 35 percent of the chimpanzees activity involved some sort of bipedal movement, and once again, this behavior appeared to be linked to a clear attempt to carry as much as possible at one time. Which of the following statements is NOT true according to the first two paragraphs()
Cement was seldom used in buildings of the Middle Ages.()
The Magic Io Personal Digital Pen 1. Check out the io Personal Digital Pen launched by Logitech: It’s a magic pen that can store everything you write and transfer it to your computer. And you don’t have to lug a hand held device along with you for it to work. 2. Logitech’s technology works like this: The pen writes normally, using normal ballpoint pen ink. But while you are writing, a tiny camera inside the pen is also taking 100 snapshots per second of what you are doing, mapping your writing via a patchwork of minute dots printed on the paper. All this information—the movement of your pen on the paper, basically—is then stored digitally inside the pen, whether you are writing notes or drawing complex diagrams. You can store up to 40 pages worth of doodles in the pen’s memory. As far as you are concerned, you are just using a normal pen. 3. It is only when you drop the pen into its PC-connected cradle that the fun begins. Special software on your PC will figure out what you have done, and begin to download any documents you have written since the last time it was there. Depending on whether you have ticked certain boxes on the special notepad, it can also tell whether the document is destined to be an e-mail, a "to do" task, or a diagram to be inserted into a word-processing document. Once the documents are downloaded you can view them, print them out or convert them to other formats. 4. The io Personal Digital Pen is a neat and simple solution to the problem of storing, sharing and retrieving handwritten notes, as well as for handling diagrams, pictures and other non text doodling. You don’t have to carry a laptop along with you. All you have to do is just to whip out the pen and the special paper and you are off. 5. It is a great product because it does not force you to work differently—walking around with a screen strapped to your arm, or carrying with you extra bits and pieces. The pen is light and works like a normal pen if you need it to, while the special notepads look and feel like notepads. The only strange looks will be from people who are curious why you are writing with a cigar. 6. The io Personal Digital Pen also has potential elsewhere. FedEx, for example, is introducing a version of the pen so that customers can fill out forms by hand—instead of punching letters into cumbersome devices. Once that data is digital more or less anything can be done with it—transferring it wirelessly to a central computer, for example, or via a hand-phone. Doctors could transmit their prescriptions directly to pharmacies, reducing fraud; policemen could send their reports back to the station, reducing paperwork. Paragraph 3 ______
Researchers Discover Why Humans Began Walking UprightMost of us walk and carry items in our hands every day. These are seemingly simple activities that the majority of us don’t question. But an international team of researchers, including Dr. Richmond from GW’s Columbian College of Arts and Sciences, have discovered that human walking upright, may have originated millions of years ago as an adaptation to carrying scarce, high-quality resources. The team of researchers from the US, England, Japan and Portugal investigated the behavior of modern-day chimpanzees as they competed for food resources, in an effort to understand what ecological settings would lead a large ape—one that resembles the 6 million-year old ancestor we shared in common with living chimpanzees—to walk on two legs."These chimpanzees provide a model of the ecological conditions under which our earliest ancestors might have begun walking on two legs ", said Dr. Richmond.The research findings suggest that chimpanzees switch to moving on two limbs instead of four in situations where they need to monopolize a resource. Standing on two legs allows them to carry much more at one time because it frees up their hands. Over time, intense bursts of bipedal activity may have led to anatomical changes that in turn became the subject of natural selection where competition for food or other resources was strong.Two studies were conducted by the team in Guinea. The first study was conducted by the team in Kyoto University’s "outdoor laboratory" in a natural clearing in Bossou Forest. Researchers allowed the wild chimpanzees access to different combinations of two different types of nut—the oil palm nut, which is naturally widely available, and the coula nut, which is not. The chimpanzees’ behavior was monitored in three situations: (a) when only oil palm nuts were available, (b)when a small number of coula nuts were available, and(c) when coula nuts were the majority available resource.When the rare coula nuts were available only in small numbers, the chimpanzees transported more at one time. Similarly, when coula nuts were the majority resource, the chimpanzees ignored the oil palm nuts altogether. The chimpanzees regarded the coula nuts as a more highly-prized resource and competed for them more intensely.In such high-competition settings, the frequency of cases in which the chimpanzees started moving on two legs increased by a factor of four. Not only was it obvious that bipedal movement allowed them to carry more of this precious resource, but also that they were actively trying to move as much as they could in one go by using everything available—even their mouths.The second study, by Kimberley Hockings of Oxford Brookes University, was a 14- month study of Bossou chimpanzees crop-raiding, a situation in which they have to compete for rare and unpredictable resources. Here, 35 percent of the chimpanzees activity involved some sort of bipedal movement, and once again, this behavior appeared to be linked to a clear attempt to carry as much as possible at one time. Kyoto University’s study discovered that chimpanzees()
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