Penn study shows why sleep is needed to form memories PHILADELPHIA – If you ever argued with your mother when she told you to get some sleep after studying for an exam instead of pulling an all-nighter, you owe her an apology, because it turns out she's right. And now, scientists are beginning to understand why. In research published this week in Neuron, Marcos Frank, PhD, Assistant Professor of Neuroscience, at the University of Pennsylvania School of Medicine, postdoctoral researcher Sara Aton, PhD, and colleagues describe for the first time how cellular changes in the sleeping brain promote the formation of memories. "This is the first real direct insight into how the brain, on a cellular level, changes the strength of its connections during sleep," Frank says. The findings, says Frank, reveal that the brain during sleep is fundamentally different from the brain during wakefulness. "We find that the biochemical changes are simply not happening in the neurons of animals that are awake," Frank says. A molecular explanation is emerging.
Artificial Robotic Hand Transmits Feeling To Nerves Astro Teller has an unusual way of starting a new project: He tries to kill it. Teller is the head of X, formerly called Google X, the advanced technology lab of Alphabet. At X’s headquarters not far from the Googleplex in Mountain View, Calif., Teller leads a group of engineers, inventors, and designers devoted to futuristic “moonshot” projects like self-driving cars, delivery drones, and Internet-beaming balloons. To turn their wild ideas into reality, Teller and his team have developed a unique approach. It starts with trying to prove that whatever it is that you’re trying to do can’t be done—in other words, trying to kill your own idea. As Teller explains, “Instead of saying, ‘What’s most fun to do about this or what’s easiest to do first?’ The ideas that survive get additional rounds of scrutiny, and only a tiny fraction eventually becomes official projects; the proposals that are found to have an Achilles’ heel are discarded, and Xers quickly move on to their next idea.
Orion Nebula | Alien Worlds: Shedding light on our unearthly universe We've been enraptured by this most eye-catching of constellations since ancient times. It's a beautiful sight that dominates our winter skies in northern latitudes. The constellation was named after Orion the Hunter, a character in Greek mythology. But those ancient stargazers could never have dreamt of the tremendous details that modern astronomy has uncovered about this star system. Story continues below animation. Download this animation from iTunes U © 2003 Torsten BrongerReproduced under the terms of the GNU Free Documentation License, Wikimedia Commons, 2008 The ‘right shoulder’ of the ‘hunter’ is a star called Betelgeuse (sometimes pronounced ‘Beetlejuice’, but that's probably not the most correct way of saying it). It's very likely that Betelgeuse will soon explode and become a spectacular supernova. The constellation's ‘left knee’ is the brilliant blue star called Rigel. But perhaps the jewel in the crown is Orion's great nebula. © C.R.
Hi-Res Images of Hydrogen Nonmetal, mass: 1.008 u, 2 stable isotopes (1, 2), abundance rank (earth/space): 9/1 Click image to magnify. Vial of glowing ultrapure hydrogen, H2. Original size in cm: 1 x 5. Hydrogen is the lightest and simplest element and, with a ratio of 80%, is the main ingredient of the visible universe. 20% consist of helium, the ratio of the heavier elements is below 1%. Right: The Great Orion Nebula, 80% hydrogen. The images are licensed under a Creative Commons Attribution 3.0 Unported License, unless otherwise noted. Why are past, present, and future our only options? But things get awkward if you have a friend. (Use your imagination if necessary.) Low blow, Dr. Dave. Low blow... But seriously, I always figured if there was more than one dimension of time, that moving "left" or "right" would be the equivalent of moving to a parallel universe where things were slightly different. That is to say, maybe time really is 2 dimensional, but for all the reasons you mention, we're normally only aware of one of them—and for the most part, the same one that most of the people we meet are aware of. But take, say, a schizophrenic person—maybe they're tuned in differently; moving sideways through time instead of forward... or maybe moving through (and aware of) both simultaneously. They can't form coherent thoughts because they're constantly confronted with overlapping and shifting realities. I dunno... that's all just speculation, of course, but I find that thought fascinating.
Interactive 3D model of Solar System Planets and Night Sky Physics Flash Animations We have been increasingly using Flash animations for illustrating Physics content. This page provides access to those animations which may be of general interest. The animations will appear in a separate window. The animations are sorted by category, and the file size of each animation is included in the listing. In addition, I have prepared a small tutorial in using Flash to do Physics animations. LInks to versions of these animations in other languages, other links, and license information appear towards the bottom of this page. The Animations There are 99 animations listed below. Other Languages and Links These animations have been translated into Catalan, Spanish and Basque: En aquest enllaç podeu trobar la versió al català de les animacions Flash de Física. Many animations have been translated into Greek by Vangelis Koltsakis. Most animations have been translated into Hungarian by Sandor Nagy, Eötvös Loránd University.
Artificial Intelligence - Volume 1: Chatbot NetLogo Model Produced for the book series "Artificial Intelligence"; Author: W. J. powered by NetLogo view/download model file: Chatbot.nlogo This model implements two basic chatbots - Liza and Harry. The model makes use of an extension to NetLogo called "re" for regular expressions. First press the setup button in the Interface - this will load the rules for each chatbot. The Interface buttons are defined as follows:- setup: This loads the rules for each chatbots.- chat: This starts or continues the conversation with the chatbot that was selected using the bot chooser. The Interface chooser and switch is defined as follows:- bot: This sets the chatbot to the Liza chatbot, the Harry chatbot or Both.- debug-conversation: If this is set to On, debug information is also printed showing which rules matched. Harry seems to do a bit better at being paranoid than Liza does at being a Rogerian psychotherapist. Try out the different chatbots by changing the bot chooser.
Laid Back - Introducing Alex Corbi The Ultimate Field Guide to Subatomic Particles This is, for the most part, an accurate article, except for a few statements. "Exactly what makes a fermion a fermion is a bit complicated, but suffice it to say that fermions are all the particles that deal with matter. So what about the last group of elementary particles, the ones that don't deal with matter? These are the bosons, and they deal with the fundamental forces of the universe." The statements above can be misinterpreted as suggesting that fermions are defined as particles that deal with matter and bosons are defined as particles that deal with forces. And that is not true. Particles that deal with matter are fermions and particles that carry the fundamental forces are bosons. What fermions and bosons really are have to do with two apparently unrelated (but actually related) particle properties: spin and statistics. "There are four known bosons" See, this is an example of the misconception I just mentioned. According to special relativity, not general relativity.
h+ Magazine | Covering technological, scientific, and cultural trends that are changing human beings in fundamental ways. Michelle Ewens March 24, 2011 The concept of utility fog – flying, intercommunicating nanomachines that dynamically shape themselves into assorted configurations to serve various roles and execute multifarious tasks – was introduced by nanotech pioneer J. Storrs Hall in 1993. Recently in H+ Magazine, Hall pointed out that swarm robots are the closest thing we have to utility fog. This brings the concept a little bit closer to reality. For instance, a few years ago Dr. However, if a future foglet ever became conscious enough to dissent from its assigned task and spread new information to the hive mind, this might cause other constituent foglets to deviate from their assigned tasks. Eric Drexler, who coined “grey goo” in his seminal 1986 work on nanotechnology, “Engines of Creation,” now resents the term’s spread since it is often used to conjure up fears of a nanotech-inspired apocalypse. What Is It Like to Be a Foglet? The Psychology of Groupthink The Ethics of Military Foglets