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The bacteria that turns water into ice. Meet Pseudomonas syringae, a bacterium that causes disease in plants and helps make snow machines work.

The bacteria that turns water into ice

It all has to do with ice nucleation — the process that forms ice crystals in the atmosphere and, thus, snow. You probably know that raindrops and snowflakes form around something. There's always a central nucleus that serves as the backbone of the water molecule structure. Usually, when people talk about this process, they use soot or some other kind of particulate matter as the example of what a nucleus can be. But bacteria can also become the nucleus of a snowflake. Here's how biologist Mark Martin described the process in the video: In my Microbiology course at the University of Puget Sound, I like to demonstrate the wild and wonderful and weird microbial world. P. syringae gets this skill from the proteins that cover its surface membrane.

Commercial snow machines use the proteins (though not the bacteria itself) to help instigate the creation of snow on ski mountains. Supercooled Helium Does Things That Don't Seem Possible. We all know helium as a gas for blowing up balloons and making people talk like chipmunks.

Supercooled Helium Does Things That Don't Seem Possible

It's also incredibly important as a coolant for medical devices and scientific instrumentation. However, what is less known is that helium has two different liquid states, one of which is truly strange, bordering on creepy. Pokemon Artificial Intelligence Is Smarter Than You. Jellyfish are the most energy-efficient swimmers, new metric confirms. When a man is tired of London house prices. ‘Since Londoners cannot seem to stop asking, “Is there a bubble?”

When a man is tired of London house prices

, I’ve been trying to figure out the answer’ I predicted the UK house price slump of 2007. I was even planning to devote an episode of my BBC2 series to the subject back in 2006, until my producers demanded a different topic. They argued that house prices would assuredly keep rising, so I would seem silly. The replacement theme was “It’s hard to predict the future”; prices duly fell by 15 per cent in real terms. This triumph should be set in context: I had been forecasting a slump in 2002, 2003, 2004 and 2005. The economics of apologies. Apologies are often hard – that’s the point.

The economics of apologies

An apology is due when trust is broken, and to restore trust the apology must be hard. This column discusses a model of apologies as costly signals with some recent experimental evidence. Following the recent wave of apologies by politicians,1 celebrities,2 and in particular by firms,3 there have been numerous commentaries about the nature of apology – in particular how it is pointless and overused. Recent research in the social science of apologies can help us understand their logic, and shed light on the purpose of the rituals of repairing social transgression. What Most Freaks Out Scholars Who Study The Future Of Humanity? How Does "Valence" Help Your Brain Distinguish Between Good And Bad? How to Read Body Language More Effectively. IBM's Watson Can Now Debate Its Opponents. "It's important to note, however, that Watson doesn't actually understand the content"

IBM's Watson Can Now Debate Its Opponents

IBM's Watson Can Now Debate Its Opponents. Chomsky on Zizek and Lacan. 2048 - Hard. Cubic Curve Calculator. A Rough Guide to Spotting Bad Science. Click to enlarge A brief detour from chemistry, branching out into science in general today.

A Rough Guide to Spotting Bad Science

This graphic looks at the different factors that can contribute towards ‘bad’ science – it was inspired by the research I carried out for the recent aluminium chlorohydrate graphic, where many articles linked the compound to causing breast cancer, referencing scientific research which drew questionable conclusions from their results. The vast majority of people will get their science news from online news site articles, and rarely delve into the research that the article is based on. Personally, I think it’s therefore important that people are capable of spotting bad scientific methods, or realising when articles are being economical with the conclusions drawn from research, and that’s what this graphic aims to do.

Note that this is not a comprehensive overview, nor is it implied that the presence of one of the points noted automatically means that the research should be disregarded. Like this: Scientists Discover New Shape When Playing With Rubber Bands. What do you yet when you cross a rubber band with an octopus?

Scientists Discover New Shape When Playing With Rubber Bands

A whole new shape, it turns out, with perversions. The Harvard researchers who made the discovery were seeking to make springs. They glued two strips of uneven length together and stretched them out while clipped at each end with strings thin enough that the strips could rotate freely. As the force stretching the strips out decreased the strips started to wind up like a telephone cord (ask someone over 30).

While the new shape resembles a double helix the team noticed it had what they call perversions (see image above). Mantis Shrimp-Inspired Material is Stronger than Airplanes. The mighty, mighty mantis shrimp is a colorful and fearsome predator that can smash its opponent (and aquariums walls) to pieces using its arms that are covered with hard exoskeleton.

Mantis Shrimp-Inspired Material is Stronger than Airplanes

Researchers hoping to harness its power have now created a material that’s stronger than what’s used in airplane frames. Also known as a stomatopd (Odontodactylus scyllarus), the 4 to 6-inch long smashing predator has a fist-like “mineralized dactyl club” that can withstand thousands of high-velocity blows, which it delivers to its prey. The force created by the impact of its club is more than 1,000 times its own weight, and underwater, the club accelerates faster than a 22-caliber bullet. The Great Filter. Sept. 15, 1998 by Robin Hanson Humanity seems to have a bright future, i.e., a non-trivial chance of expanding to fill the universe with lasting life.

The Great Filter

But the fact that space near us seems dead now tells us that any given piece of dead matter faces an astronomically low chance of begating such a future. There thus exists a great filter between death and expanding lasting life, and humanity faces the ominous question: how far along this filter are we? Combining standard stories of biologists, astronomers, physicists, and social scientists would lead us to expect a much smaller filter than we observe. Lab gets funding to put 3D goggles on praying mantises. It sounds like the kind of research project that a future a Congressman might hold up as an example of wasteful government spending: gluing a praying mantis to a stick and putting mini-3D goggles on it.

Lab gets funding to put 3D goggles on praying mantises

But this project is very real and pretty neat, and it should actually tell us something about neurobiology. Symbol addition by monkeys provides evidence for normalized quantity coding. Author Affiliations Edited* by Jon H. Kaas, Vanderbilt University, Nashville, TN, and approved March 28, 2014 (received for review March 4, 2014) Significance. Kevlar. Un article de Wikipédia, l'encyclopédie libre. Le poly(p-phénylènetéréphtalamide) (PPD-T) est un polymère thermoplastique constitué de noyaux aromatiques séparés par des groupes amide.

Il appartient à la famille des fibres d'aramides. Le PPD-T est commercialisé sous le nom déposé de Kevlar. Ce dernier, comme les autres fibres textiles, ne fait pas partie des matières plastiques. New Study Outlines 'Water World' Theory of Life's Origins. Music information retrieval. Music information retrieval (MIR) is the interdisciplinary science of retrieving information from music. MIR is a small but growing field of research with many real-world applications. Those involved in MIR may have a background in musicology, psychology, academic music study, signal processing, machine learning or some combination of these. Applications of MIR[edit] MIR is being used by businesses and academics to categorize, manipulate and even create music.

Recommender systems[edit] Several recommender systems for music already exist, but surprisingly few are based upon MIR techniques, instead making use of similarity between users or laborious data compilation. Mel-frequency cepstrum. In sound processing, the mel-frequency cepstrum (MFC) is a representation of the short-term power spectrum of a sound, based on a linear cosine transform of a log power spectrum on a nonlinear mel scale of frequency. Mel-frequency cepstral coefficients (MFCCs) are coefficients that collectively make up an MFC. They are derived from a type of cepstral representation of the audio clip (a nonlinear "spectrum-of-a-spectrum").

Mel scale. Plots of pitch mel scale versus Hertz scale Play . 440 Hz = 549.64 mels A popular formula to convert. v5.pdf. Approximate string matching. Fuzzy Mediawiki search for "angry emoticon": "Did you mean: andré emotions" Overview[edit] The closeness of a match is measured in terms of the number of primitive operations necessary to convert the string into an exact match.

This number is called the edit distance between the string and the pattern. The usual primitive operations are:[1] insertion: cot → coatdeletion: coat → cotsubstitution: coat → cost. Mesh networking. Illustration of a mesh network. Self-Learning Helicopter Uses Neural Network. Coursera's Android App Allows You to Download Lectures For Mobile Use. Forensic Scientists Build Crude 3D Mugshots From DNA. DNA evidence was first used to help solve crimes in 1986, but it didn’t hit the main stage of the public’s attention until it was used in OJ Simpson’s murder trial in 1994. Dying to Live: Terrorism, War, and Defending One's Way of Life by Kenneth Vail, Matt Motyl, Abdolhossein Abdollahi, Tom Pyszczynski. The first official "chaos machine" is easy to make. Did Life On Earth As We Know It Come From ‘Geological Life’? Want to stay on top of all the space news?

17 Equations That Changed The World. The smartphone app that could rescue the world's plankton. Life. College - Experience it Firsthand. In September 2013, Berry’s original bald eagle couple was once again seen on the Berry College campus in the vicinity of the nest in a tall pine tree situated between the main entrance and the parking lot of the Steven J. Cage Athletic and Recreation Center. [1210.1847] Constraints on the Universe as a Numerical Simulation. Is the Universe a Simulation?

Photo Gray Matter By EDWARD FRENKEL. Global Forest Watch. How Science Turned a Struggling Pro Skier Into an Olympic Medal Contender - Wired Science. Steven Nyman is poised at the starting gate, alert, coiled, ready. Self-Assembling Molecules Like These May Have Sparked Life on Earth - Wired Science. When his students successfully converted chemical precursors into an RNA-like molecule in the form of a yellow gel, Nicholas Hud scribbled down the surprising recipe. Image: Nicholas Hud. Urban Computing Reveals the Hidden City. Why strange loops could be an argument for artificial intelligence. Shepard tone. Shepard Tone: l'arme secrète de Ricardo Villalobos dévoilée. Shepard Tone: l'arme secrète de Ricardo Villalobos dévoilée.

Gamme de Shepard. Shepard Tone. Shepard Tone. Genes, Macromolecules, -&- Computing: Strange loops in biology. Strange Loop. Why strange loops could be an argument for artificial intelligence. Nuclear fusion hits energy milestone - Technology & Science. Systematic network lesioning reveals the core white matter scaffold of the human brain. The First Map Showing All the Connections in Your Brain's White Matter. Miniature bouncing tennis balls reveal cellular interiors. The Difference Between Knowledge and Experience.

Tableau Périodique Dynamique - Compound. Elliptic curve. A (Relatively Easy To Understand) Primer on Elliptic Curve Cryptography. Two Generals' Problem. Making Makers. Massive Open Lab gets volunteers to beat computers in designing RNA. Gamers beat algorithms at finding protein structures. Evolution vs Natural Selection. The Infinite Hotel Paradox - Jeff Dekofsky. BAHFest 2013 - Tomer Ullman: The Crying Game. A New Scientific Model that Defines Alien Intelligence. How Skynet Might Emerge From Simple Physics. Physicist proposes a thermodynamic explanation for the origins of life. Visualization of Narrative. Scientists watch glowing molecules form memories in real time. Google acquires AI pioneer DeepMind Technologies. One of the strangest animals on earth gets a little weirder. 50 of the Best Online Courses and Resources for Learning Web Design. Latest Data Shows Global Climate Continues Warming Trend. Notification : stratégie - filtrage des URL. Chemical process turns any plant matter—even trees—into biofuels. Mill, Principles of Political Economy. Giant laser could arrange particles into enormous space telescope. Giant laser could arrange particles into enormous space telescope.

Three arguments about climate change that should never be used. Amelia Earhart: Breaking Barriers of Earth and Sky. Lexical Distance Among the Languages of Europe « Etymologikon™ CountryData—Wolfram Language Documentation. Language & System Documentation Center. Sophisme. Fuzzy-trace theory. Academic Publications by Stephen Wolfram. The Nature of Code. Cellular automaton.

Automate cellulaire.