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POPSMore Evidence for a Revolutionary Theory of Water The current study is the most recent addition to a growing body of evidence for a new theory about the structure of liquid water. In 2004, Nilsson and colleagues sparked controversy with a paper published in Science that suggested the tetrahedral model of water was incorrect. Nilsson agrees that the debate is far from settled and that much work remains before a clear picture of liquid water emerges. "Over the last decade or so we have discovered that materials once considered homogeneous exhibit complex nanoscale order," said Stanford Synchrotron Radiation Laboratory director Jo Stöhr. "In my view, the work on water is yet another example of the actual complexity of matter, this time within a simple liquid. Modern X-ray work appears to be triggering a new understanding of liquids and we may have only seen the beginning of a paradigm shift in our understanding."
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POPSWhy we may overlook extra-terrestrial life Ammonia, for example, has many of the same properties as water. An ammonia or ammonia-water mixture, stays liquid at much colder temperatures than plain water.Hydrogen fluoride methanol, hydrogen sulfide, hydrogen chloride, and formamide have all been suggested as suitable solvents that could theoretically support alternative biochemistry. All of these “water replacements” have pros and cons when considered in our terrestrial environment. What needs to be considered is that with a radically different environment, comes radically different reactions. Water and carbon might be the very last things capable of supporting life in some extreme planetary conditions. In any case, it is not beyond the realm of feasibility that our first encounter with extra-terrestrial life will not be a solely carbon-based occasion.
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POPSThe color of plants on other worlds What color will alien plants be? The question matters scientifically because the surface color of a planet can reveal whether anything lives there—specifically, whether organisms collect energy from the parent star by the process of photosynthesis. Photosynthesis is adapted to the spectrum of light that reaches organisms. This spectrum is the result of the parent star’s radiation spectrum, combined with the filtering effects of the planet’s atmosphere and, for aquatic creatures, of liquid water. Light of any color from deep violet through the near-infrared could power photosynthesis. Around stars hotter and bluer than our sun, plants would tend to absorb blue light and could look green to yellow to red. Around cooler stars such as red dwarfs, planets receive less visible light, so plants might try to absorb as much of it as possible, making them look black.<<
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POPSEarth could seed Titan with life Dr Gladman's team calculated that up to 20 terrestrial rocks from a large impact on Earth would reach Titan. These would strike Titan's upper atmosphere at 10-15 km/s. At this velocity, the cruise down to the surface might be comfortable enough for microbes to survive the journey.But the news was more bleak for Europa. By contrast with the handful that hit Titan, about 100 terrestrial meteoroids hit the icy moon. "It's frustrating if you're a microbe that's been wandering the Universe for a million years to then die striking the surface of Europa," Dr Gladman mused.Asked after his presentation by one scientist whether he thought microbes would be able to survive Titan's freezing temperatures, Dr Gladman answered: "That's for you people to decide, I'm just the pizza delivery boy."
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POPSIce Volcanoes of Titan May Habor Life For almost thirty years, scientists have known that complex carbon compounds called tholins exist on comets and in the atmospheres of the outer planets. Theoretically, tholins might interact with water in a process called hydrolysis to produce complex molecules similar to those found on the early Earth. Could tholins formed in Titan's atmosphere react with liquid water temporarily exposed by meteor impacts or ice volcanoes to produce potentially prebiotic complex organic molecules — before the water freezes? Laboratory research by Catherine Neish, a graduate student working on her doctorate in planetary science at the University of Arizona, suggests, not without controversy, however, that, over a period of days, compounds similar to tholins can be react with water at near-freezing temperatures.
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POPSSmart amoebas reveal origins of primitive intelligence "Now they have identified a potential storage device. The amoeba's interior contains a watery sol – a solid suspended in liquid – within a thick viscous gel. The sol flows through the gel like water through a sponge, creating a network of low-viscosity channels. Those channels are strengthened as long as the amoeba continues to respond to a static environment, but if that environment changes the channels gradually break down and a new network appears as the amoeba adapts. For a short while, though, the amoeba retains a “memory” of those earlier conditions."
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POPS12 Uses For Vinegar I couldn't do without it. I buy it by the gallon! Vinegar is really good for removing calcium build-up and as a hair conditioner too (especially if you have hard water) It shines up my kitchen sink like a charm and put a little in the water bucket when you wash windows for a streak free view. Mix a little with some yoghurt and you have an excellent aftersun lotion that works better than any store-bought variety IMO and it helps avoid peeling if you get sunburnt. Zap a cup of it and the microwave oven becomes a breeze to clean. Save LOTS of money and lower your use of toxic chemicals coz it's eco-friendly too!
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POPSSeeing the Invisible Schlieren photography, which “takes an invisible phenomenon and turns it into a visible picture”... Schlieren is German for “streaks”; in this case it refers to regions of different densities in a gas or a liquid, which can be photographed as shadows using a special technique. Beautiful...
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POPSBio Lego -MIT & Harvard Scientists Create Living Building Blocks The self-assembly is based on "the thermodynamic tendency of multiphase liquid–liquid systems to minimize their contact surfaces", the most awesomely complicated way of saying "oil and water don't mix" possible. By preparing polyethylene microgel components and adding them to an oil/water mixture, the specially shaped bits align themselves along the spherical liquid interfaces. Applying a few seconds of UV light fixes the microgel in position and you have a ready made, biocompatible (and degradable) matrix ready for the addition of cells. Replicating the different tissue organizations of different organs becomes nothing more than a recipe book, choosing your initial microcomponents, mixture and baking time.
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