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Submission + - Physicists explain 'gravity-defying' chain trick (nature.com)

Submitted by ananyo
ananyo writes: Leaping up out of a jar in an arc before falling to the floor, the fountain-like motion of a chain of beads has puzzled millions around the world with its apparently gravity-defying behaviour. Now physicists think they have an explanation.
British science presenter Steve Mould, who made the experiment famous, explained the phenomenon as simply one of inertia: the falling chain has downward momentum, causing an upward momentum in beads leaving the pot. This, in turn, makes them leap before gravity can slowly reverse their momentum.
Mould’s explanation was clever, but wrong, says physicist John Biggins of the University of Cambridge, UK. The only way to account for the rise is for the chain to receive a 'kick' from the pot from which it is being pulled. This challenges not only the explanation given by Mould, but the conventional mathematics of chains, Biggins says.

Submission + - Request for Funding OpenBSD HQ's Electricity

Submitted by Anonymous Coward
An anonymous reader writes: The OpenBSD Project started a Request for Funding our Electricity. As Undeadly.org writes:

OpenBSD supports a wide range of hardware architectures, and for practical and logistical reasons there are few places in the world that have them all in one place except OpenBSD headquarters [...] But keeping all this hardware running involves a considerable electricity bill, and Theo de Raadt (deraadt@) is asking for help, preferably in the form of a company willing to specifically sponsor the project's electricity bill.

Donations are greatly appreciated and bigger donations can go to the OpenBSD Foundation which will help with details and can provide receipts.

Submission + - Sweden is closing many prisons due to lack of prisoners. (rtoz.org)

Submitted by rtoz
rtoz writes: Sweden is taking steps to close many prisons due to lack of prisoners.

This year alone, four prisons and a detention center got closed in Sweden.

The percentage of the population in Sweden prison is significantly lower than in most other countries.

And,the Swedish prison system is not generally severe. For example, the top-of-the-line prison in Sollentuna, Sweden includes cells with comfortable mattresses and private bathrooms. After prisoners hit the weight room, they can cook up a meal in the state of the art kitchen before kicking back and watching TV on the couch. Sweden’s prison authorities are quick to point out that every square inch of the prison can be seen on a security camera.

Though the Sweden Government is taking steps to close the prisons, crime rate in sweden is not reduced. Actually Crime rate it getting increased in Sweden. It seems they are planning to take steps for preventing the crimes than focusing on sentencing the people involve in criminal activities.

Comment Why not a balloon (Score 1) 143

Why not a ballon, of the size of a giant hat, make of a tinfoil? If would need to be tilted somewhat, and turn itself towards the sun -- easy in the case of a ballon. Would not it be much cheaper? Of course, tinfoil does not have the directionality of a glass mirror, but make the hat big enough and it would not be a problem, and even be a feature -- the more ambient light would not decrease the iris size so much, and thus a human would perceive the lighted area as even more bright.
Java

Submission + - Oracle Releases February Java Security To Deal with Live Exploit (infoq.com)

Submitted by Anonymous Coward
An anonymous reader writes: Oracle has published a major security update for Java. The update was originally scheduled for February 19th, but was released a fortnight early on Friday because of "active exploitation 'in the wild' of one of the vulnerabilities affecting the Java Runtime Environment (JRE) in desktop browsers".

From the article
"According to the latest Oracle Risk Matrix, the update covers a total of 50 flaws: 49 of these can be remotely exploited — in other words just visiting a web page, for instance, might be enough to infect your computer; 26 carry the maximum Common Vulnerability Scoring System (CVSS) risk score of 10. Oracle hasn't said which of the remote code execution holes is the one that's actively being exploited but it is addressed with this patch."

Submission + - Artificial energy storage island in the North-Sea (standaard.be)

Submitted by bmcage
bmcage writes: Belgium wants to build within 5 years an artificial [dutch] energy storage island ([Google Translate]). The island will store excess energy produced at night from the offshore wind farms already present in the North-Sea.

As a small country with no hydropower possibilities, moving from nuclear to offshore wind farms, this is an innovative way to store the excess production. Is it really feasible however? Silting could be a problem.
Medicine

Submission + - Australian scientists discover potential aids cure

Submitted by smi.james.th
smi.james.th writes: Several sites report that Australian researcher David Harrich and his team have potentially discovered a way to stop HIV becoming AIDS and ultimately cure the disease. From the article: "What we've actually done is taken a normal virus protein that the virus needs to grow, and we've changed this protein, so that instead of assisting the virus, it actually impedes virus replication and does it quite strongly." This could potentially hail one of modern medicine's greatest victories.
Science

Submission + - "Superomniphobic" nanoscale coating repels almost any liquid (gizmag.com) 1

Submitted by cylonlover
cylonlover writes: A team of engineering researchers at the University of Michigan has developed a nanoscale coating that causes almost all liquids to bounce off surfaces treated with it. Creating a surface structure that is least 95 percent air, the new "superomniphobic" coating is claimed to repel the broadest range of liquids of any material in its class, opening up the possibility of super stain-resistant clothing, drag-reducing waterproof paints for ship hulls, breathable garments that provide protection from harmful chemicals, and touchscreens resistant to fingerprint smudges.

Comment Re:Titius-Bode law (Score 1) 62

by art6217 (#42214751) Attached to: Nearby Solar System Looks Like Home
This is not only about fitting a random formula. A set of such formulas would give more information on the rule in question:
  • is this just an exponential fit?
  • or is this an exponential fit i_1 + i_2 * i_3^m, that tends to contain small integers i_j?
  • or does it tend to be exactly an exponential fit a = 4 + 3 * 2^m?

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