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The Hacker Academy takes its members on an impressive journey from the hacker's perspective. THA delves into the psyche of a hacker: what they want, how they will get it - and an "it takes one to know one mentality". Our philosophy at The Hacker Academy is that members will be armed with the knowledge necessary to practice, implement, and deploy what they have learned immediately and effectively. All training modules are available 24/7 and are perfect for any skill level.

The Khan Academy is a not-for-profit 501(c)(3) with the mission of providing a world-class education to anyone, anywhere. We are complementing Salman's ever-growing library with user-paced exercises--developed as an open source project--allowing the Khan Academy to become the free classroom for the World.

"Log in to your Khan Academy account and earn energy points for the videos you watch."

The supply of secure, clean, sustainable energy is arguably the most important scientific and technical challenge facing humanity in the 21st century. Rising living standards of a growing world population will cause global energy consumption to double by mid-century and triple by the end of the century. Even in light of unprecedented conservation, the additional energy needed is simply not attainable from long discussed sources these include nuclear, biomass, wind, geothermal and hydroelectric. The global appetite for energy is simply too much. Petroleum-based fuel sources (i.e., coal, oil and gas) could be increased. However, deleterious consequences resulting from external drivers of economy, the environment, and global security dictate that this energy need be met by renewable and sustainable sources. The dramatic increase in global energy need is driven by 3 billion low-energy users in the non-legacy world and by 3 billion people yet to inhabit the planet over the next half century. The capture and storage of solar energy at the individual level personalized solar energy drives inextricably towards the heart of this energy challenge by addressing the triumvirate of secure, carbon neutral and plentiful energy. This talk will place the scale of the global energy issue in perspective and then discuss how personalized energy (especially for the non-legacy world) can provide a path to a solution to the global energy challenge. Daniel G. Nocera is the Henry Dreyfus Professor of Energy at the Massachusetts Institute of Technology, Director of the Solar Revolutions Project and Director of the Eni Solar Frontiers Center at MIT. His group pioneered studies of the basic mechanisms of energy conversion in biology and chemistry. He has recently accomplished a solar fuels process that captures many of the elements of photosynthesis outside of the leaf. This discovery sets the stage for a storage mechanism for the large scale, distributed, deployment of solar energy. He has b

"Yong-Guan Zhu (Chinesische Akademie der Wissenschaften, Peking) et al.: Proceedings of the National Academy of Sciences (PNAS), doi: 10.1073/pnas.1222743110" Im Mist aus großen Schweinefarmen fanden sie knapp 150 bakterielle Resistenzgene in großen Mengen. Diese, so warnen sie, sind hoch mobil und machen krankmachende Keime gegen nahezu alle bekannten Antibiotika immun.

"Meet the future of security training. Expert instructors. Hands-on labs. On your schedule."

New research looks at the effects of studying a form of meditation on brain connectivity. Writing in the Proceedings of the National Academy of Science, researchers in China and the University of Oregon describe experiments on 45 students, some of whom were taught a meditation technique known as integrative body-mind training (IBMT). The researchers used brain imaging techniques to examine fibers connecting brain regions before and after training. Students trained in the IBMT approach for 11 hours or more appeared to develop new fibers in a part of the brain that helps a person regulate behavior. Control subjects did not form the new fibers. But what does the presence of those fibers actually mean -- and what is the meditation technique doing? We'll talk about it.

Researchers at Columbia and Rockefeller Universities have identified cells in the stomach that regulate the release of a hormone associated with appetite. The group is the first to show that these cells, which release a hormone called ghrelin, are controlled by a circadian clock that is set by mealtime patterns. The finding, published in Proceedings of the National Academy of Sciences, has implications for the treatment of obesity and is a landmark in the decades-long search for the timekeepers of hunger.

"A quest that began over a decade ago with a chance observation has reached a milestone: the identification of a gene that may regulate regeneration in mammals. The absence of this single gene, called p21, confers a healing potential in mice long thought to have been lost through evolution and reserved for creatures like flatworms, sponges, and some species of salamander. In a report published today in the Proceedings of the National Academy of Sciences, researchers from The Wistar Institute demonstrate that mice that lack the p21 gene gain the ability to regenerate lost or damaged tissue."

COULD the structure of space and time be sketched out inside a cousin of plain old pencil lead? The atomic grid of graphene may mimic a lattice underlying reality, two physicists have claimed, an idea that could explain the curious spin of the electron. Graphene is an atom-thick layer of carbon in a hexagonal formation. Depending on its position in this grid, an electron can adopt either of two quantum states - a property called pseudospin which is mathematically akin to the intrinsic spin of an electron. Most physicists do not think it is true spin, but Chris Regan at the University of California, Los Angeles, disagrees. He cites work with carbon nanotubes (rolled up sheets of graphene) in the late 1990s, in which electrons were found to be reluctant to bounce back off these obstacles. Regan and his colleague Matthew Mecklenburg say this can be explained if a tricky change in spin is required to reverse direction. Their quantum model of graphene backs that up. The spin arises from the way electrons hop between atoms in graphene's lattice, says Regan. So how about the electron's intrinsic spin? It cannot be a rotation in the ordinary sense, as electrons are point particles with no radius and no innards. Instead, like pseudospin, it might come from a lattice pattern in space-time itself, says Regan. This echoes some attempts to unify quantum mechanics with gravity in which space-time is built out of tiny pieces or fundamental networks (Physical Review Letters, vol 106, p 116803). Sergei Sharapov of the National Academy of Sciences of Ukraine in Kiev says that the work provides an interesting angle on how electrons and other particles acquire spin, but he is doubtful how far the analogy can be pushed. Regan admits that moving from the flatland world of graphene to higher-dimensional space is tricky. "It will be interesting to see if there are other lattices that give emergent spin," he says.

Apply the electrodes... Externally modulating the brain's activity can boost its performance. The easiest way to manipulate the brain is through transcranial direct current stimulation (tDCS), which involves applying electrodes directly to the head to influence neuron activity with an electric current. Roi Cohen Kadosh's team at the University of Oxford showed last year that targeting tDCS at the brain's right parietal lobe can boost a person's arithmetic ability - the effects were still apparent six months after the tDCS session (newscientist.com/article/dn19679). More recently, Richard Chi and Allan Snyder at the University of Sydney, Australia, demonstrated that tDCS can improve a person's insight. The pair applied tDCS to volunteers' anterior frontal lobes - regions known to play a role in how we perceive the world - and found the participants were three times as likely as normal to complete a problem-solving task (newscientist.com/article/dn20080). Brain stimulation can also boost a person's learning abilities, according to Agnes Flöel's team at the University of Münster in Germany. Twenty minutes of tDCS to a part of the brain called the left perisylvian area was enough to speed up and improve language learning in a group of 19 volunteers (Journal of Cognitive Neuroscience, DOI: 10.1162/jocn.2008.20098). Using the same technique to stimulate the brain's motor cortex, meanwhile, can enhance a person's ability to learn a movement-based skill (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas.0805413106).

ScienceDaily (Apr. 26, 2011) - In a paper published in the April 25 early online edition of the Proceedings of the National Academy of Sciences, researchers at the University of California, San Diego School of Medicine, the Gladstone Institutes in San Francisco and colleagues report a game-changing advance in stem cell science: the creation of long-term, self-renewing, primitive neural precursor cells from human embryonic stem cells (hESCs) that can be directed to become many types of neuron without increased risk of tumor formation.