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Speculative connections between electric lighting, sleep deficits, and health.

I wonder if the driving force behind the sleep deficit is in fact more pervasive, and indeed global in nature: the triumph of light.

Graphene is a single-atom-thick sheet made from combined carbon atoms. The carbon atoms are bonded together to share electron in a hexagonal, honeycomb-like structure. It is a single atom thick layered 2D material ever discovered in the world. It is made up of a hexagonal lattice pattern of carbon atoms in a monolithic honeycomb-like structure. It is a layer of SP2 single bonded carbon atoms arranged like a chicken wire mesh. It is 200 times stronger than stainless steel (SS) and 100 thousand times thinner than the human hair. It is the slimmest and strongest compound available on the earth. Anybody would be amazed when they know that we have found a material which is harder than diamond, yet lightweight, stronger than steel, but also highly flexible, and this material can be mined from the earth as it occurs naturally. It is yet thin enough to be mistaken for a saran wrap. Apart from the optimum physical properties, the other features are also impressive. Properties of Graphene These are some prominent features which make it a hi-tech material: Excellent Electronic Conductor Chief electronic property makes it an efficient Zero-Overlap Semi metal and gives it sufficient electrical conductivity. Carbon atoms possess typically 2 electrons in the inner shell, and 4 electrons in the outer orbit, total 6 electrons. Although conventionally, the outer 4 electrons in carbon can connect with another atom, each, the atoms can form a 2-dimensional bond with three atoms per single atom. This leaves an electron available for electronic conduction. Such electrons are known as 'Pi' electrons and found above and below in sheet. Ultimate Tensile Strength Mechanical strength is another prominent property of the material. It considered as being the foremost most robust material ever discovered, owing to the 0.142 Nm-long carbon bonds. It also possesses ultimate tensile strength, measuring 130 Gigapascals (or 130,000,000,000 Pascals). Compared to the tensile strength of industr

This method may potentially be suitable for designing novel light sources resembling lasers that work in the x-ray range. Among other applications, they might allow building more powerful computer chips.

(PhysOrg.com) -- A group of physicists working out of Chalmers University of Technology in Gothenburg, Sweden, have succeeded in proving what was until now, just theory; and that is, that visible photons could be produced from the virtual particles that have been thought to exist in a quantum vacuum. In a paper published on arXiv, the team describes how they used a specially created circuit called a superconducting quantum interference device (SQUID) to modulate a bit of wire length at a roughly five percent of the speed of light, to produce visible "sparks" from the nothingness of a vacuum.

Free Download - StanfordUniversity - January 22, 2009 - Karl Deisseroth is pioneering bold new treatments for depression and other psychiatric diseases. By sending pulses of light into the brain, Deisseroth can control neural activity with remarkable precision. In this short talk, Deisseroth gives an thoughtful and awe-inspiring overview of his Stanford University lab's groundbreaking research in "optogenetics".

ScienceDaily (Dec. 3, 2010) - IBM scientists have unveiled a new chip technology that integrates electrical and optical devices on the same piece of silicon, enabling computer chips to communicate using pulses of light (instead of electrical signals), resulting in smaller, faster and more power-efficient chips than is possible with conventional technologies.

some researchers at the MIT Media Lab are aiming to put the controls back in people's hands, in a way that provides sophisticated and continuous control and could slash lighting bills by more than half.

Engineers at Stevens Institute of Technology have developed a technique to optically modulate the frequency of a laser beam and create a signal that is disrupted significantly less by environmental factors, says Dr. Rainer Martini. The research provides for enhanced optical communications, allowing mobile units not tied to fiber optic cable to communicate in the range of 100 GHz and beyond, the equivalent of 100 gigabytes of data per second. Eventually, the team hopes to extend the reach into the terahertz spectrum. The frequency or amplitude modulation of middle infrared quantum cascade lasers has been limited by electronics, which are barely capable of accepting frequencies of up to 10 GHz by switching a signal on and off.  Marini and his team have developed a method to optically induce fast amplitude modulation in a quantum cascade laser to control the laser's intensity. Their amplitude modulation system employed a second laser to modulate the amplitude of the middle infrared laser, using light to control light. The current detector is only capable of detecting frequencies up to 10 GHz, but Dr. Martini is confident that a new detector will make the system capable of much higher frequencies. With an optical system that is stable enough, satellites may one day convert to laser technology, resulting in a more mobile military and super-sensitive scanners, as well as faster Internet for the masses, says Martini. Ref.: "Optically induced fast wavelength modulation in a quantum cascade laser," Applied Physics Letters, July 7, 2010.

ScienceDaily (July 11, 2011) - Researchers at Columbia Engineering School have built optical nanostructures that enable them to engineer the index of refraction and fully control light dispersion.

Typically, a solar cell generates a single electron for each photon captured. However, by adding pentacene, an organic semiconductor, the solar cells can generate two electrons for every photon from the blue light spectrum. This could enable the cells to capture 44% of the incoming solar energy.

LEDsThe strange quantum state of entanglement isn't just challenging to think about, it's hard to create. This "spooky" phenomenon-in which two particles are linked, even if they're separated by distance-can be created by scientists in the lab using bulky lasers. But scientists published a study in Nature today in which they created a light-emitting diode (LED) that produces entangled photons.

A new process that simultaneously combines the light and heat of solar radiation to generate electricity could offer more than double the efficiency of existing solar cell technology, say the engineers who discovered it and proved that it works. The process, called 'photon enhanced thermionic emission," or PETE, could reduce the costs of solar energy production enough for it to compete with oil as an energy source.

Creating a laser that can melt a soda can in a lab is a finicky enough task. Later this year, scientists will put a 40,000-pound chemical laser in the belly of a gunship flying at 300 mph and take aim at targets as far away as five miles. And we're not talking aluminum cans. Boeing's new Advanced Tactical Laser will cook trucks, tanks, radio stations-the kinds of things hit with missiles and rockets today. Whereas conventional projectiles can lose sight of their target and be shot down or deflected, the ATL moves at the speed of light and can strike several targets in rapid succession.

Professor Andre Geim, who along with his colleague Professor Kostya Novoselov won the 2010 Nobel Prize for graphene - the world's thinnest material, has now modified it to make fluorographene - a one-molecule-thick material chemically similar to Teflon. Fluorographene is fully-fluorinated graphene and is basically a two-dimensional version of Teflon, showing similar properties including chemical inertness and thermal stability.

Historians, sociologists, philosophers and sometimes scientists themselves have begun to ask fundamental questions about how the institution of science is structured and how it knows what it knows. David Cayley talks to some of the leading lights of this

Superconductivity describes the phenomenon where an electric current is able to travel through a material without any resistance - the material is a perfect electrical conductor without any energy loss.

Low-Cost Multi-point Interactive Whiteboards Using the Wiimote Since the Wiimote can track sources of infrared (IR) light, you can track pens that have an IR led in the tip. By pointing a wiimote at a projection screen or LCD display, you can create very low-cost interactive whiteboards or tablet displays. Since the Wiimote can track upto 4 points, up to 4 pens can be used. It also works great with rear-projected displays.

ScienceDaily (June 9, 2011) - Scientists have just reported that the tiny light-sensing cells known as rods have been clearly and directly imaged in the living eye for the first time. Using adaptive optics (AO), the same technology astronomers use to study distant stars and galaxies, scientists can see through the murky distortion of the outer eye, revealing the eye's cellular structure with unprecedented detail. This innovation, described in two papers in the Optical Society's (OSA) open access journal Biomedical Optics Express, will help doctors diagnose degenerative eye disorders sooner, leading to quicker intervention and more effective treatments.

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