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LeopoldS

The Moon's mantle unveiled - 2 views

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    first science results reported in Nature (as far as I know) from the Yutu-2 and Chang'e mission .... and they look very good!
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    Sure they are very useful! It will be even better if they manage to fit the data to modeled circulation of the lunar magma ocean that was formed posterior to the "Theia" body collision with Earth. The collision was the cause of the magma ocean in the first place. The question now is how this circulation pattern of the lava-moon "froze" in time upon phase transition to solid. Because, what crystallizes last in sequence, is more rich in "incompatible" with the crystal structure, elements, we might combine data+models to predict their location. Those incompatible tracers are mainly radioactively decaying elements that produce heat (google publications about lunar KREEP elements (potassium (K), rare earth elements(REE), and phosphorus(P)). By knowing where the KREEP is: - we know where to dig for them mining (if they are useful for something, eg. Phosphorus for plants to be grown on the Moon) - we avoid planning to build the future human colony on top of radioactives, of course. The hope is that the Moon, due to lack of plate tectonics, has preserved this "signature of the freezing sequence". Let's see.
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    thanks Nasia! very interesting comment
jcunha

New method uses heat flow to levitate variety of objects - 1 views

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    Normally we associate levitation of objects to superconducting materials. Here a new technique is shown where levitation of a whole new range of materials is shown. "The large temperature gradient leads to a force that balances gravity and results in stable levitation," said Fung, the study's lead author. "We managed to quantify the thermophoretic force and found reasonable agreement with what is predicted by theory. This will allow us to explore the possibilities of levitating different types of objects." Paper at http://aip.scitation.org/doi/10.1063/1.4974489 New microgravity experiments possibility?
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    not really I fear .... "Typical sizes of the trapped particles are between 10 μm and 1 mm at a pressure between 1 and 10 Torr. The trapping stability is provided radially by the increasing temperature field and vertically by the transition from the free molecule to hydrodynamic behavior of thermophoresis as the particles ascend."
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    Might still be OK micro to mm sized experiments. The technique seems to be reliable and cheap enough to compete with other types of microgravity approaches - more research needed to define boundaries of course.
jcunha

ALPHA observes light spectrum of antimatter for first time - 1 views

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    The ALPHA collaboration reports the first ever measurement on the optical spectrum of an antimatter hydrogen atom. Optical transitions shown to be the same as for normal hydrogen. Paper at http://www.nature.com/nature/journal/vaap/ncurrent/full/nature21040.html#affil-auth
albertosantos

A Cloaking Device for Transiting Planets - 5 views

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    Cloaking Laser could hide us from "evil aliens "
Thijs Versloot

Breakthrough observation of Mott transition in a superconductor - 1 views

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    An international team of researchers, including the MESA+ Institute for Nanotechnology at the University of Twente in The Netherlands and the U.S. Department of Energy's Argonne National Laboratory, announced today in Science the observation of a dynamic Mott transition in a superconductor.
annaheffernan

Filamentous laser beams point to new type of phase transition - applications in weather control - 2 views

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    Filaments of plasma created by a high-powered laser beam undergo a similar type of phase transition as liquid percolating through a porous material - that is the conclusion of physicists in Switzerland. The also describe the application of laser filamentation for directed lightening and encouraged rainfall - Isabelle should come back to take a closer look :p
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    Christophe? Isabelle?
Thijs Versloot

Hypersonic Successor to Legendary SR-71 Blackbird Spy Plane Unveiled - 1 views

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    he new SR-72 will use a turbine-based combined cycle (TBCC) that will employ the turbine engine at lower speeds, and use a scramjet at higher speeds. A scramjet engine is designed to operate at hypersonic velocities by compressing the air through a carefully designed inlet, but needs to be traveling supersonic before it is practical to begin with. So far research projects from NASA, the Air Force and other Pentagon entities have not been able to solve the problem of transitioning from the subsonic flight regime, through hypersonic flight with a single aircraft. Same problem as Reaction Engines is trying to solve, so I am not sure whether they actually cracked it. In any case, nice pictures. Not sure why the exhaust color is purple in color. Its not running on Argon I believe.
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    Weird article. Intermediate thruster stage (Ramjet) is missing. Scramjet has supersonic combustion and a normal turbine delivers subsonic flows. Even with afterburner - the Scramjet inlet would decelerate the flow down to subsonic velocity with "normal" subsonic combustion. The only thing I can imagine is that the Scramjet stage is bi-functional and covers both, subsonic and supersonic combustion. But the article doesn't say anything about it.
annaheffernan

Plasmons excite hot carriers - 1 views

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    The first complete theory of how plasmons produce "hot carriers" has been developed by researchers in the US. The new model could help make this process of producing carriers more efficient, which would be good news for enhancing solar-energy conversion in photovoltaic devices.
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    I did not read the paper but what is further down written in the article, does not give much hope that this actually gives much more insight than what we had nor that it could be used in any way to improve current PV cells soon: e.g. "To fully exploit these carriers for such applications, researchers need to understand the physical processes behind plasmon-induced hot-carrier generation. Nordlander's team has now developed a simple model that describes how plasmons produce hot carriers in spherical silver nanoparticles and nanoshells. The model describes the conduction electrons in the metal as free particles and then analyses how plasmons excite hot carriers using Fermi's golden rule - a way to calculate how a quantum system transitions from one state into another following a perturbation. The model allows the researchers to calculate how many hot carriers are produced as a function of the light frequency used to excite the metal, as well as the rate at which they are produced. The spectral profile obtained is, to all intents and purposes, the "plasmonic spectrum" of the material. Particle size and hot-carrier lifetimes "Our analyses reveal that particle size and hot-carrier lifetimes are central for determining both the production rate and the energies of the hot carriers," says Nordlander. "Larger particles and shorter lifetimes produce more carriers with lower energies and smaller particles produce fewer carriers, but with higher energies."
LeopoldS

NIAC 2014 Phase I Selections | NASA - 4 views

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    12 new NIAC 1 studies - many topics familiar to us ... please have a look at those closest to your expertise to see if there is anything new/worth investigating (and in general to be knowledgeable on them since we will get questions sooner or later on them)
    Principal Investigator Proposal Title Organization City, State, Zip Code
    Atchison, Justin Swarm Flyby Gravimetry Johns Hopkins University Baltimore, MD 21218-2680
    Boland, Eugene Mars Ecopoiesis Test Bed Techshot, Inc. Greenville, IN 47124-9515
    Cash, Webster The Aragoscope: Ultra-High Resolution Optics at Low Cost University of Colorado Boulder, CO 80309-0389
    Chen, Bin 3D Photocatalytic Air Processor for Dramatic Reduction of Life Support Mass & Complexity NASA ARC Moffett Field, CA 94035-0000
    Hoyt, Robert WRANGLER: Capture and De-Spin of Asteroids and Space Debris Tethers Unlimited Bothel, WA 98011-8808
    Matthies, Larry Titan Aerial Daughtercraft NASA JPL Pasadena, CA 91109-8001
    Miller, Timothy Using the Hottest Particles in the Universe to Probe Icy Solar System Worlds John Hopkins University Laurel, MD 20723-6005
    Nosanov, Jeffrey PERISCOPE: PERIapsis Subsurface Cave OPtical Explorer NASA JPL Pasadena, CA 91109-8001
    Oleson, Steven Titan Submarine: Exploring the Depths of Kraken NASA GRC Cleveland, OH 44135-3127
    Ono, Masahiro Comet Hitchhiker: Harvesting Kinetic Energy from Small Bodies to Enable Fast and Low-Cost Deep Space Exploration NASA JPL Pasadena, CA 91109-8001
    Streetman, Brett Exploration Architecture with Quantum Inertial Gravimetry and In Situ ChipSat Sensors Draper Laboratory Cambridge, MA 02139-3539
    Wiegmann, Bruce Heliopause Electrostatic Rapid Transit System (HERTS) NASA MSFC Huntsville, AL 35812-0000
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    Eh, the swarm flyby gravimetry is very similar to the "measuring gravitational fields" project I proposed in the brewery
LeopoldS

Sex differences in the structural connectome of the human brain - 0 views

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    it seems that there are indications that we are differently wired .... Sex differences in human behavior show adaptive complementarity: Males have better motor and spatial abilities, whereas females have superior memory and social cognition skills. Studies also show sex differences in human brains but do not explain this complementarity. In this work, we modeled the structural connectome using diffusion tensor imaging in a sample of 949 youths (aged 8-22 y, 428 males and 521 females) and discovered unique sex differences in brain connectivity during the course of development. Connection-wise statistical analysis, as well as analysis of regional and global network measures, presented a comprehensive description of network characteristics. In all supratentorial regions, males had greater within-hemispheric connectivity, as well as enhanced modularity and transitivity, whereas between-hemispheric connectivity and cross-module participation predominated in females. However, this effect was reversed in the cerebellar connections. Analysis of these changes developmentally demonstrated differences in trajectory between males and females mainly in adolescence and in adulthood. Overall, the results suggest that male brains are structured to facilitate connectivity between perception and coordinated action, whereas female brains are designed to facilitate communication between analytical and intuitive processing modes.
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    I like this abstract: sex, sex, sex, sex, SEX, SEX, SEX, SEX...!!! I wonder if the "sex differences" are related to gender-specific differences...
Isabelle Dicaire

Art meets critical transitions - 2 views

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    An art movie on critical transitions from scientist Marten Scheffer!!
LeopoldS

David Miranda, schedule 7 and the danger that all reporters now face | Alan Rusbridger | Comment is free | The Guardian - 0 views

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    During one of these meetings I asked directly whether the government would move to close down the Guardian's reporting through a legal route - by going to court to force the surrender of the material on which we were working. The official confirmed that, in the absence of handover or destruction, this was indeed the government's intention. Prior restraint, near impossible in the US, was now explicitly and imminently on the table in the UK. But my experience over WikiLeaks - the thumb drive and the first amendment - had already prepared me for this moment. I explained to the man from Whitehall about the nature of international collaborations and the way in which, these days, media organisations could take advantage of the most permissive legal environments. Bluntly, we did not have to do our reporting from London. Already most of the NSA stories were being reported and edited out of New York. And had it occurred to him that Greenwald lived in Brazil?

    The man was unmoved. And so one of the more bizarre moments in the Guardian's long history occurred - with two GCHQ security experts overseeing the destruction of hard drives in the Guardian's basement just to make sure there was nothing in the mangled bits of metal which could possibly be of any interest to passing Chinese agents. "We can call off the black helicopters," joked one as we swept up the remains of a MacBook Pro.

    Whitehall was satisfied, but it felt like a peculiarly pointless piece of symbolism that understood nothing about the digital age. We will continue to do patient, painstaking reporting on the Snowden documents, we just won't do it in London. The seizure of Miranda's laptop, phones, hard drives and camera will similarly have no effect on Greenwald's work.

    The state that is building such a formidable apparatus of surveillance will do its best to prevent journalists from reporting on it. Most journalists can see that. But I wonder how many have truly understood
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    Sarah Harrison is a lawyer that has been staying with Snowden in Hong Kong and Moscow. She is a UK citizen and her family is there. After the miranda case where the boyfriend of the reporter was detained at the airport, can Sarah return safely home? Will her family be pressured by the secret service? http://www.bbc.co.uk/news/world-latin-america-23759834
Thijs Versloot

Supercooled water transforms into new form of liquid - 0 views

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    A liquid-liquid phase transition at 207K. The research is aimed at understanding what happens when thawing tissues from cyroprotection
johannessimon81

New Supergel Has Strange Biological Properties - 0 views

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    Linked to the discussion we had last week on elastically non-linear polymers. The inverted liquid->solid phase transition might be interesting and the material might be self-healing just above the transition.
LeopoldS

Equilibrated High-Density Amorphous Ice and Its First-Order Transition to the Low-Density Form - The Journal of Physical Chemistry B (ACS Publications) - 1 views

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    water does not seem to be water ... or there seem to be two waters somehow ...
Lionel Jacques

Hubble to Watch Historic Venus Transit, Using Moon as Mirror - 2 views

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    "Scientists are planning to use NASA's Hubble Space Telescope to observe next month's historic transit of Venus across the sun's face. But there's a twist. Researchers can't point Hubble anywhere near the sun, because our star's bright light could damage the telescope's super-sensitive instruments. So Hubble will watch the June 5-6 Venus transit by using the moon as a mirror."
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    aha. i suggested something like this a few years ago
santecarloni

New Kind of Metal in the Earth | Geophysical Laboratory - 0 views

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    New experiments and supercomputer computations discovered that iron oxide undergoes a new kind of transition under deep Earth conditions. Iron oxide, FeO, is a component of the second most abundant mineral at Earth's lower mantle, ferropericlase. The finding, published in an upcoming issue of Physical Review Letters, could alter our understanding of deep Earth dynamics and the behavior of the protective magnetic field, which shields our planet from harmful cosmic rays.
LeopoldS

Statistically induced phase transitions and anyons in 1D optical lattices : Nature Communications : Nature Publishing Group - 1 views

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    sante have a look .... Anyons ... !!
LeopoldS

Experimental Detection of Trinitramide, N(NO2)3 - Rahm - 2010 - Angewandte Chemie International Edition - Wiley Online Library - 0 views

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    Dejan have a look at this ...
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    Would be nice to have some cross sections or transition probabilities for the possible transition (or decomposition) channels. But anyway, HEDM is one of the key short/mid-term topics in advanced energy, power, and/or propulsion.
LeopoldS

French National Police Force saves €2 million a year with Ubuntu | Canonical - 0 views

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    Be careful, the article is written by the company who did the migration to Ubuntu. Here is a comment by a police guy from IT (in french...). In brief he says that tyhe migration was not a problem for most of the people; exepc for some probleme with access. But it did cost money ! and the saving was not the main argument. "Personnellement concerné par la news qui n'en est pas une, je peux vous assurer que le message de Canonical est surtout commercial... Le choix d'Ubuntu est dû à son hégémonie et le fait que ce soit basé sur du Debian qui est considéré comme très stable. La distrib est d'une maintenance plus aisée que la plupart de celles qui ont été testées. "4500 postes" veut dire "4500 unités de gendarmerie" donc dans les brigades que vous connaissez... Pour ce qui est d'OpenOffice, le passage s'est fait assez tranquillement sauf pour les applis Access qui ont eu un peu de mal à passer sur le module Base...La plupart ont été reprise au sein d'applis php/mysql ou d'applis centralisées... Aujourd'hui, les gendarmes qui je le rappelle ne sont pas informaticiens mais vivent pour vous (au sens le plus strict je vous l'assure) utilisent donc firefox/thunderbird et oppenoffice en clients lourds, le reste étant des applis sur l'intranet ou "invisibles" pour l'utilisateur. Le passage à Ubuntu ne gène en rien dans l'utilisation car le trio précédemment cité est déjà connu et maîtrisé par nombre de mes collègues. Je ne suis pas censé m'exprimer en lieu et place de mes supérieurs mais à titre personnel, le choix d'Ubuntu est un choix intelligent car c'est une distribution avec une prise en main très accessible et avec une maintenance vraiment aisée pour les spécialistes informatiques dont je fais partie...Il ne faut pas oublier qu'une distribution plus élitiste aurait été maîtrisée par moins de monde et donc la maintenance aurait été plus coûteuse... Donc aujourd'hui nous "maîtrisons" cette part de notre infrastructure et la trans
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    Lotus Notes doesn't run on Linux anyway...
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