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Submission + - The Mystery of Acupuncture Explained in Rat Model-> 1

hackingbear writes: A biological mechanism explaining part of the mystery of the acupuncture has been pinpointed by scientists studying rats. The research showed that applying electroacupuncture to an especially powerful acupuncture point known as stomach meridian point 36 (St36) affected a complex interaction between hormones known as the hypothalamus pituitary adrenal (HPA) axis. In stressed rats exposed to unpleasant cold stimulation, HPA activity was reduced. The findings provide the strongest evidence yet that the ancient Chinese therapy has more than a placebo effect when used to treat chronic stress, it is claimed. “Some antidepressants and anti-anxiety drugs exert their therapeutic effects on these same mechanisms,” said lead investigator Dr Ladan Eshkevari, from Georgetown University medical centre in Washington DC.
Link to Original Source

Submission + - Famous Fluid Equations Are Incomplete->

An anonymous reader writes: While Hilbert’s broader aim of axiomatizing physics remains unfulfilled, recent research has yielded an unexpected answer to the particle-fluid question. The Boltzmann equation does not translate into the Navier-Stokes equations in all cases, because the Navier-Stokes equations — despite being exceptionally useful for modeling the weather, ocean currents, pipes, cars, airplane wings and other hydrodynamic systems, and despite the million-dollar prize offered for their exact solutions — are incomplete. The evidence suggests that truer equations of fluid dynamics can be found in a little-known, relatively unheralded theory developed by the Dutch mathematician and physicist Diederik Korteweg in the early 1900s. And yet, for some gases, even the Korteweg equations fall short, and there is no fluid picture at all.

“Navier-Stokes makes very good predictions for the air in the room,” said Slemrod, who presented the evidence last month in the journal Mathematical Modelling of Natural Phenomena. But at high altitudes, and in other near-vacuum situations, “the equations become less and less accurate.”

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Submission + - FBI releases Erdos files after MuckRock FOIA request->

v3rgEz writes: A Hungarian born in the early 20th century, Paul (Pal) Erdos, mathematician, was well-known and well-liked, the sort of eccentric scientist from the Soviet sphere that made Feds’ ears perk up in mid-century America. His lifetime generated over five hundred scholarly papers and a cult of collaborators. The Erdos number has become a mathy merit badge, and for those that don’t hold a coveted Erdos number of 1, there are resources to determine just how many degrees of celebrity separation exist between the man himself and other technical paper bylines.

And like almost all smart individuals of his era, Erdos had a lengthy FBI file — which ultimately concluded no nefarious intent, but rather "nothing to indicate the subject had any interest in any matter than Mathematics." Read on for highlights, or read Erdos' full FBI file.

Link to Original Source

Exploring the Relationships Between Tech Skills (Visualization) 65

Nerval's Lobster writes: Simon Hughes, Dice's Chief Data Scientist, has put together an experimental visualization that explores how tech skills relate to one another. In the visualization, every circle or node represents a particular skill; colors designate communities that coalesce around skills. Try clicking "Java", for example, and notice how many other skills accompany it (a high-degree node, as graph theory would call it). As a popular skill, it appears to be present in many communities: Big Data, Oracle Database, System Administration, Automation/Testing, and (of course) Web and Software Development. You may or may not agree with some relationships, but keep in mind, it was all generated in an automatic way by computer code, untouched by a human. Building it started with Gephi, an open-source network analysis and visualization software package, by importing a pair-wise comma-separated list of skills and their similarity scores (as Simon describes in his article) and running a number of analyses: Force Atlas layout to draw a force-directed graph, Avg. Path Length to calculate the Betweenness Centrality that determines the size of a node, and finally Modularity to detect communities of skills (again, color-coded in the visualization). The graph was then exported as an XML graph file (GEXF) and converted to JSON format with two sets of elements: Nodes and Links. "We would love to hear your feedback and questions," Simon says.

A Computer That Operates On Water Droplets 67

Okian Warrior notes a Stanford project to build a basic computer that operates on water droplets. One of its creators, Manu Prakash, says the goal is not to compete with digital computers for manipulating data (though they can theoretically perform all of the same computations). Instead, "Our goal is to build a completely new class of computers that can precisely control and manipulate physical matter. Imagine if when you run a set of computations that not only information is processed but physical matter is algorithmically manipulated as well." The biggest obstacle in creating the water computer was figuring out a way to develop a clock mechanism. The team decided to use a rotating magnetic field, which is both precise and easy to control. To get it to interact with the water, they put arrays of tiny iron bars on glass slides, and then added a layer of oil, and finally another glass slide. Magnetized water droplets are injected into this scaffolding, and the magnetic field can then easily push them along paths created by the iron. "It's about manipulating matter faster," Prakash said.

A Ph.D Thesis Defense Delayed By Injustice 77 Years 134

Taco Cowboy writes: A story about a 102-year old lady doing her PhD thesis defense is not that common, but when the thesis defense was delayed by a whopping 77 years, that gotta raise some eyebrows. Ingeborg Syllm-Rapoport studied diphtheria at the University of Hamburg in Germany and in 1938, the 25-year old Protestant-raised, German-born Ingeborg submitted for her doctorate thesis defense. She was denied her chance for her defense because her mother was of the Jewish ancestry, making her an official "cross-breed". As such the Nazi regime forbid the university from proceeding with her defense, for "racial reasons".

She became one of the thousands of scholars and researchers banished from German academe, which at the time included many of the world's most prestigious research institutions, because of Jewish ancestry or opposition to Nazi policies. Many of them ended up suffering or dying in concentration camps. Rudolf Degkwitz, Syllm's professor, was imprisoned for objecting to euthanizing children. Syllm, however, was able to reach the United States and earned her medical degree from the old Women's Medical College of Pennsylvania in Philadelphia. Eventually she married a fellow physician named Samuel Mitja Rapoport, had a family, and moved back to Germany in the 1950s, where she achieved prominence in neonatology. Syllm-Rapoport, who is now 102 years old, might have remained just a doctor (if a very accomplished one) had not the present dean of the Hamburg medical school, Uwe Koch-Gromus, heard her story from a colleague of her son, Tom Rapoport, a Harvard cell biologist.

Determined to do what he could to mitigate this wrong, Koch-Gromus arranged Syllm-Rapoport's long-delayed defense. Despite failing eyesight, she brushed up on decades of developments in diphtheria research with the help of friends and the Internet. Koch-Gromus called the 45-minute oral exam given by him and two colleagues on 13 May in her Berlin living room "a very good test. Frau Rapoport has gathered notable knowledge about what's happened since then. Particularly given her age, she was brilliant."

Uber Will Provide Transit Data To Cities 32

mpicpp notes that transportation company Uber will be sharing the transit data it collects with city governments in order to "provide new insights to help manage urban growth, relieve traffic congestion, expand public transportation, and reduce greenhouse gas emissions." The company's first partnership will be with Boston, where Uber and other ridesharing services have been formally recognized by the state. Mayor Walsh said, "[D]ata is driving our conversations, our policy making and how we envision the future of our city. We are using data to change the way we deliver services and we welcome the opportunity to add to our resources. This will help us reach our transportation goals, improve the quality of our neighborhoods and allow us to think smarter, finding more innovative and creative solutions to some of our most pressing challenges."

Space Tourism Isn't Worth Dying For 594

rudy_wayne writes with this opinion piece at Wired published in the wake of the crash of SpaceShipTwo, which calls the project nothing more than a "millionaire boondoggle thrill ride." A selection: SpaceShipTwo is not a Federation starship. It's not a vehicle for the exploration of frontiers. Virgin Galactic is building the world's most expensive roller coaster, the aerospace version of Beluga caviar. It's a thing for rich people to do. Testing new aircraft takes a level of courage and ability beyond most humans. Those engineers and pilots are at the peak of human achievement. What they're doing is amazing. Why Virgin is doing it is not. When various corporate representatives eulogize those two pilots as pioneers who were helping to cross the Final Frontier, that should make you angry. That pilot died not for space but for a luxury service provider. His death doesn't get us closer to Mars; it just keeps rich people further away from weightlessness and a beautiful view.

Comment Saving Earth's resources? (Score 2) 243

As about one fourth of world electricity consumption is used for lighting purposes, the LEDs contribute to saving the Earth's resources.

Efficiency does not mean lower consumption. Efficiency remains a useful goal but not "to save the planet's resources". The latter can happen only if overall consumption is reduced. What will happen is that as electricity used for lighting purposes is consumed less, it will get cheaper to direct it elsewhere.

Comment Re:Black holes are real, we observe them all the t (Score 1) 356

Maybe he should have meant the following version which seems very counter-intuitive:

Suppose you wrap a string around the Earth's equator so that it fits tightly. Now suppose you add an extra meter in the length of that string. Surely, the string won't be tight anymore. So pinch it at a point and pull it upwards as high as you can. (Now, the string goes tightly around most of the earth, and forms a triangle elsewhere with the apex being the point you pinched and pulled.)

How high this apex would be from the surface? The answer turns out to be well over a hundred meters. See Image 1

(Apart from the actual number, the surprising part is also that the bigger the initial object - earth here - the higher you can pull the string even though you add the same extra length of 1 m in each case.)

Comment Re:Read the whole article (Score 1) 136

Also, either the author of the article has a listening comprehension problem or the assitant professor quoted in the article has a reading comprehension problem.

Look at Turing's original article. It says that the imitation game is played between a man (A), a woman (B), and a player C. C has to decide among A and B who is a man and who is a woman. Now, the _man_ is replaced is a computer and we ask if C will perform as well or poorly as before.

So in Turing's version we have a computer A pretending to be a woman to C, and a woman trying to convince C that she is the woman.

Turning's original test _does not_ have a man and a computer pretending to be a woman to a judge.


The Profoundly Weird, Gender-Specific Roots of the Turing Test 136

malachiorion writes: Alan Turing never wrote about the Turing Test, that legendary measure of machine intelligence that researchers claimed to have passed last weekend. He proposed something much stranger — a contest between men and machines, to see who was better at pretending to be a woman. The details of the Imitation Game aren't secret, or even hard to find, and yet no one seems to reference it. This article explains why they should — in part because it's so odd, but also because it might be a better test for 'machines that think' than the chatbot-infested, seemingly useless Turing Test.

Comment Re:the joker in the formula (Score 1) 686

There are 7 billion people on earth but only one tallest person. Clearly the odds of finding a tallest being on any planet is 1:7_billion.

The point of parent is that if the intelligent "us" were not us, someone else would have evolved to be as intelligent. You can argue that point but don't argue probabilities based on 1 out of however many being intelligent. Two intelligent species would have competed and one would be killed off so far in earth's history.

Comment Re:Fascinating, terrifying stuff is news (Score 1) 358

Do you realize that the whole point of the GP's "exercise" was that you can't ignore relativity? It is due to relativity that the time observed by the traveller would be so little. If you are travelling at a velocity very close to the speed of light, in your own frame time is essentially standing still. You would get to your destination before you could blink your eye.

Now redo the calculations taking time dilation into account.

Comment Usual /. (Score 4, Informative) 82

The summary (and the headline) unnecessarily highlights space travel as a usage for radiation pressure and delegates the most interesting part as a footnote-ish last line. The /. crowd as usual starts shouting pros and cons of space travel, as if every comment on this page is not saying what has already been said a million time around here, and nobody to talk about the interesting part.

I wish someone with the right background in physics posted something more interesting about the fact that a group of researchers have come up with prediction of how a non-quantized spacetime (gravity) would look in the presence of quantized matter/energy. Apparently this would look different than a quantized background with quantized foreground (IANAP, so I don't know what is this all about) in a measurable way. If they can levitate a tiny but macroscopic mirror using light and balance it then giving it a gentle push would create a pendulum with no friction slowing it down. By probing the frequency evolution one can potentially get closer to actually knowing whether a quantum theory of gravity is the right way to unify QM and GR.

It's fascinating that such things are possible even in principle with existing technology. I wish someone would explain something more related to this.

Somebody ought to cross ball point pens with coat hangers so that the pens will multiply instead of disappear.