1. Business Insider - A planned shale gas drilling project in New York state has drawn global attention for its aim to make use of a waterless form of hydraulic fracking – a new technique designed to reduce the pollution associated with controversial natural gas drilling processes.
Scientists at the Naval Research Laboratory have demonstrated, for the first time, the use of graphene as a tunnel barrier — an electrically insulating barrier between two conducting materials through which electrons tunnel quantum mechanically. They report fabrication of magnetic tunnel junctions using graphene, a single atom thick sheet of carbon atoms arranged in a honeycomb lattice, between two ferromagnetic metal layers in a fully scalable photolithographic process. Their results demonstrate that single-layer graphene can function as an effective tunnel barrier for both charge and spin-based devices, and enable realization of more complex graphene-based devices for highly functional nanoscale circuits, such as tunnel transistors, non-volatile magnetic memory and reprogrammable spin logic.
Diagram (left) of the graphene-based magnetic tunnel junction, where a single atom thick layer of carbon atoms in a honeycomb lattice separates two magnetic metal films (cobalt and permalloy). The magnetizations of the films can be aligned parallel or antiparallel, resulting in a change in resistance for current flowing through the structure, called the tunnel magnetoresistance (TMR). The plot (right) shows the TMR as an applied magnetic field changes the relative orientation of the magnetizations — the TMR persists well above room temperature.
(U.S. Naval Research Laboratory)
Kurzweilai - Neuroscientist Kenneth Hayworth wants his 100 billion neurons and more than 100 trillion synapses to be encased in a block of transparent, amber-colored resin — before he dies of natural causes.
Hayworth’s brain-preservation and mind-uploading protocol
Before becoming “very sick or very old,” he’ll opt for an “early ‘retirement’ to the future,” he writes. There will be a send-off party with friends and family, followed by a trip to the hospital. After Hayworth is placed under anesthesia, a cocktail of toxic chemicals will be perfused through his still-functioning vascular system, fixing every protein and lipid in his brain into place, preventing decay, and killing him instantly.
Then he will be injected with heavy-metal staining solutions to make his cell membranes visible under a microscope. All of the water will then be drained from his brain and spinal cord, replaced by pure plastic resin.
Every neuron and synapse in his central nervous system will be protected down to the nanometer level, Hayworth says, “the most perfectly preserved fossil imaginable.”
Using a ultramicrotome (like one developed by Hayworth, with a grant by the McKnight Endowment Fund for Neuroscience), his plastic-embedded preserved brain will eventually be cut into strips, and then imaged in an electron microscope. The physical brain will be destroyed, but in its place will be a precise map of his connectome.
In 100 years or so, Hayworth says, scientists will be able to determine the function of each neuron and synapse and build a computer simulation of the mind. And because the plastination process will have preserved his spinal nerves, the computer-generated mind can be connected to a robot body.
“This isn’t cryonics, where maybe you have a .001 percent chance of surviving,” he said. “We’ve got a good scientific case for brain preservation and mind uploading.”
Chronicle Review - The Strange Neuroscience of Immortality
Kenneth J. Hayworth, Electron Imaging Technology for Whole Brain Neural Circuit Mapping, International Journal of Machine Consciousness, 2012, DOI: 10.1142/S1793843012400057
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Technology Review - Jie Zou et al at the University of Florida have carved a single device out of silicon that is capable of measuring the Casimir force between a pair of parallel silicon beams, the first on-chip device capable of doing this.
There are other forces at play here too, such as residual electrostatic forces. When Zou and co take these into account, their results more or less exactly match theoretical predictions for the Casimir force that beams of this shape should generate.
The device solves a number of problems. First, because both silicon beams are made in the same lithographic step, unwanted distortions are not a significant problem. And the positioning is easier to control too since the beams and actuator are all part of the same device and so need far less calibrating and alignment. Finally, there are the measurements themselves which are more straightforward to do on a single chip than in previous experiments.
All this adds up to a significant step forward. What these guys have built is the first on-chip machine that exploits the Casimir force generated by a specific geometric configuration.
Arxiv - Geometry-dependent Casimir forces on a silicon chip (11 pages)
We report measurements of the Casimir force gradient between two parallel silicon beams with near-square cross sections at separations down to 260 nm. Both the force-sensing element and the actuator that controls the distance are integrated on the same substrate, with no need for manual alignment. Taking residual electrostatic forces into consideration, the measured Casimir force gradient agrees with the theoretical calculation based on the exact geometry. This scheme opens the possibility of tailoring the Casimir force using lithographically defined components of non-conventional shapes. The set-up of the experiment and device. (a) A simplified schematic (not to scale) of the beam, movable electrode and comb actuator supported by four springs, with electrical connections. The current amplifier provides a virtual ground to the right end of the beam. The suspended and anchored parts of the comb actuator are shown in dark and light colors respectively. The separation d between the beam and the movable electrode was controllably reduced so that the Casimir force can be detected. (b)-(e) Scanning electron micrographs of the entire micromechanical structure (b) and close-ups of: the doubly clamped beam (c), zoomed into the white dashed box in (b); the comb actuator (d) and the serpentine spring (e).
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Technology Review - A layer of nanomaterial that gives a liquid-crystal display the rich range of colors usually possible only with more expensive technologies will be commercialized later this year by the materials giant 3M and Nanosys, a private company in Palo Alto, California. Nanosys representatives say they are in talks with major display manufacturers to adopt the quantum-dot films, and that they will be in a 15.6-inch notebook computer available next year.
Liquid-crystal displays (LCDs) dominate the market for both televisions and portable electronics. For many years now, manufacturers have concentrated on making LCDs on a large scale at ever lower costs, to the point where they have become commodities. Meanwhile, more expensive display technologies based on organic light-emitting diodes (OLEDs) have come along, offering richer color and, in some cases, better power consumption, but at a higher price.
Representatives from Nanosys say their film—a sheet of plastic embedded with nanoscale spheres of indium-phosphide and cadmium quantum dots—makes it possible to match the color gamut of an OLED in an LCD, without any changes to the manufacturing process, and without adding much cost.
Nano boost: A film loaded with quantum dots (left) can be added to an LCD to improve its color gamut. The film converts some of the blue light emitted by the screen's backlight (right) into red and green light. Nanosys
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WattsUpWithThat.com (Anthony Watts) reports on a new set of papers at Berkeley University on world temperature which shows half the temperature increase of previous IPCC studies.
A new paper authored by Anthony Watts, et al as part of the Berkley Earth Surface Temperature Project (BEST) (being submitted for publication) has now shown that the temperature guage site metadata (information about site changes like urban development, site moves, etc) used by NOAA and NASA's GHCN and resulting data adjustments overcompensated on high quality rural sites and undercompensated on poor quality urban sites, leading to overmodification of the temperature record, thus falsely showing a 0.308 C warming since 1979, when a new site rating methodology now shows the actual warming since 1979 has only been 0.15 C. Note the old, incorrect, exaggerated warming of 0.308 C has consistently been shown to be roughly half of the amount of warming predicted by the best computer climate models used by NOAA, NASA, and CRU to produce their predictions for the UN's IPCC report.
Anthony Watts, President, IntelliWeather, Chico, CA, USA
Evan Jones, IntelliWeather, Chico, CA, USA
Stephen McIntyre, Toronto, Canada
John R. Christy, Department of Atmospheric Science, University of Alabama, Huntsville, AL, USA
NY Times has an article by co-author physicist Richard Muller There seem to be at least two Berkeley Earth teams.
Call me (Richard Muller) a converted skeptic. Three years ago I identified problems in previous climate studies that, in my mind, threw doubt on the very existence of global warming. Last year, following an intensive research effort involving a dozen scientists, I concluded that global warming was real and that the prior estimates of the rate of warming were correct. I’m now going a step further: Humans are almost entirely the cause.
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