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Submission Summary: 0 pending, 24 declined, 9 accepted (33 total, 27.27% accepted)

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Submission + - The death of dark matter? (

slew writes: A team led by Case Western Reserve University researchers has found a significant new relationship in spiral and irregular galaxies: the acceleration observed in rotation curves tightly correlates with the gravitational acceleration expected from the visible mass only.

This correlation appears to be true of galaxies that would be apparently dominated by "halos" of dark matter in the current standard models which include dark matter to explain the mass/rotational anomalies in such galaxies.

The observations that enabled this result are the infrared measurements by the Spitzer space telescope which are considered more accurate indicators of stellar mass.

Unfortunately this new result does nothing to explain the observation of galactic expansion or apparent dark energy. So it is probably premature to throw in the towel, but hey settled science is too boring ;^)

Submission + - There are four quarks! (

slew writes: Although last year saw the first LHC observations of pentaquark particles, apparently there are indeed tetraquark particles too! And the LHC found four of them (coincidence?) Even more interesting, although they apparently each have a unique internal structure, mass and their own sets of quantum numbers, all of the four particles apparently contain the same quark composition (charm,anti-charm,strange,anti-strange). Weird stuff ;^)

Submission + - Killing two Schrödinger's cats with one stone... (

slew writes: If it wasn't enough that inside a box, you can have a half alive, half dead cat, apparently you can split a quantum mechanical "cat" into two boxes and through the wonders of quantum entanglement, you might be able kill two cats with one stone...

Okay, they didn't use real cats, or boxes (just a microwaves in a resonator cavity), but they performed an actual experiment, not just a thought experiment.

Apparently, this entertaining research might have some actual practical uses for circuit quantum electrodynamics (cQED) in some sort of boring (yawn) quantum computer error correction capacity, someday... But I'm still waiting for the real cat experiment...

Submission + - Japanese researchers build rock-paper-scissors robot that wins 100% of the time (

slew writes: Although the robot technically it cheats because it watches your hand and can recognize what shape you are intending to make and beat it before you even know what is happening. Apparently it takes about 60ms for you to shape your hand, but the robot can recognize the shape before it is completed, and only takes 20ms to counter your shape so the results appear to the human opponent to be virtually simultaneous.

I wonder how difficult it would be to add lizard and spock to the mix.... ;^)

Here is a paper with the details and a press account or two. There are videos in the links in case you want to see it in action.

Submission + - Wait, isn't there a hole in the that wheel ( 1

slew writes: Apparently after looking at some recent pictures from Curiosity's Hand Lens imager, someone spotted a hole in one of Curiosity's wheels. Unfortunatly, Mars is a long way from the nearest AAA, and the waranty on most aluminum wheels don't cover you if you decide to drive w/o tires, but apparently it's gonna be okay ;^)

Submission + - 100% fail rate on Liberia University's admission exam

slew writes: Apparently none of the 24K+ students who sat for the 2013 Liberia University entrance exam got a passing mark, and fewer than a hundred managed to pass the either the english (pass level 70%) or math (pass level 50%) sections required to qualify to be part of the normal class of 2k-3k students admitted every year...

Historically, the pass rate has been about 20-30% and in recent years, the test has been in multiple-guess format to facilitate grading. The mathematics exam generally focuses on arithmetic, geometry, algebra, analytical geometry and elementary statistic and probability; while the English exam generally focuses on grammar, sentence completion, reading comprehension and logical reasoning.

However, as a testatment to the over-hang of a civil war, university over-crowding, corruption, social promotion, the admission criteria was apparently temporarily dropped to 40% math and 50% english to allow the provisional admission of about 1.6K students. And people are calling foul...

Submission + - UC online courses' alarming growth rate (

slew writes: In the shadow of Stanford and Harvard offering free on-line courses, The University of California has been attempting to offer pay-courses for credit. UC online took out a $6.9M loan from UC and spent $4.3M to market these courses. For their efforts, they've been able to quadruple their enrollment year over year.

The first year results: one person paid $1,400 for an online calculus class worth 4 credits. Now 4 people are signed up. Me thinks head will roll on this one...


Submission + - Stable Negative Temperature System Created (

slew writes: Scientists at Ludwig Maximilian University of Munich in Germany have created an actual stable system which has an inverted Boltzmann Distribution (aka, Negative Temperature) by using an intermediate bosonic Mott insulator together with a Feshbach resonance in bosonic Potassium with laser cooling.

Although Negative Temperature systems are not uncommon (a pumped laser creates them all the time), they are not usually stable as they are not in thermodynamic equilibrium (in the case of a laser, the high energy state couples to a lower energy state returning the system to a positive temperature realm).

Practical uses are of course far away (they only achieved a billionth of a Kelvin below absolute zero), but studying stable negative temperature systems may help us understand the mechanisms behind dark energy theories.


Submission + - M-Carbon: 50yro mystery solved ( 1

slew writes: Unlike its more famous carbon cousins: diamonds and fullerenes, you've probably never heard of M-Carbon, but this form of compressed graphite which is as hard as diamonds has baffled researcher for half a century. Over the past few years, many theoretical computations have suggested at least a dozen different crystal structures for this phase of carbon, but new experiments showed that only one crystal structure fits the data: M-carbon.

Submission + - the ultimate accessory: iphone case stun-gun (

slew writes: In case you aren't in the loop, this army-reservist came up with this limited edition case for the iphone that doubles as a 650K volt stun-gun. He apparently came up with the idea after being a victim of a home invasion robbery attempt...

Bonus: the stun-gun battery pack can give an extra 20 hours of life to the iPhone if you aren't stunning anyone


Submission + - Scientists capture shadow cast by 1 atom (

slew writes: Scientist at Griffith University have shown the first absorption image of a single atom isolated in a vacuum. A single atomic ion was confined in an RF Paul trap and the absorption imaged at near wavelength resolution with a phase Fresnel lens.

They predict this absorbption imaging technique should prove useful in quantum information processing and using the minimum amount of illumination for bio-imaging of light-sensitive samples.

Here's a pointer to the paper...


Submission + - Uniformed individuals promote democratic consensus in animal groups (

slew writes: Although this isn't "new" research, I just saw this presentation at a GPU Technology Conference keynote. The gist of this research is that a well functioning democracy (a group that is nominally controlled by the numerical majority) seems to require a minimum number of uninfomed or weak-preference individuals to avoid manipulation by a strongly opinionated minority. If this is true, perhaps electing a certain percentage of spin-less clue-less flip-flopping people as legistative representatives instead of all partisan opinionated intransigents is the evolutionary prefered path to take? Nah!

Submission + - photovoltaic powered retinal prosthetic (

slew writes: Although it hasn't been tested on humans yet, stanford researchers have created a new type of retinal prosthetic that is photovoltaic powered. The gist is that external googles convert an image into infrared light and that light conveys both the image and the power for the retinal implant which means no batteries, or bulky induction coils are required for the retinal implant. This should allow for higher resolution implant (the experimental device has 176 pixels where in contrast the currently available retinal implant from SecondSight is about 60 pixels and requires a bulky inductive antenna). Might be a while till we get to a bionic eye, but this should be quite a help for the sight challenged among us.

Submission + - GraphExeter for better solar cells. (

slew writes: Transparent conducting films are a very important part of photoelectric cells and display panels like OLEDS. Unfortunatly, the currently best known material Indium Tin Oxide (aka ITO) is a rare and expensive and much better performing than it's cheaper subsitute (aluminium zinc oxide AZO). Carbon nanotubes thin-films have been considered, but are current limited by sheet resistance. A research group from University of Exeter has created a new Few-Layered graphene (FLG) w/Ferric Chloride "sandwich" which helps to limit the sheet resistance w/o affecting the transparency. If this type of material becomes practical, it could be a good replacement for ITO (which some say economical supplies will run out soon ~2017).

Submission + - Massive rise in myopia ( 1

slew writes: According to this recent study submitted to lancet, an alarming 80-90% of students in east Asian cities have myopia. The study speculates that the culture of educational pressure combined with reduced exposure to outdoor light have conspired to create this epidemic. This conclusion was drawn from a recent retrospective study at cambridge which correlated extra hours outdoors with reduced chance of myopia (~2% drop for each additional hour per week spent out-of-doors).

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