Science and Nature

Brain implants sound strange, like something out of sci-fi, but they’re closer than you think. Researchers at the A*Star Institute of Microelectronics in Singapore have developed a neural probe array small enough that it can sit inside someone’s brain on a long-term basis without damaging delicate tissue. The probe array is so compact that it can float along with a person’s brain inside their head. Their specialty: helping amputees and people with spinal cord injuries control artificial limbs.

The neural array forms a link between the brain and artificial limbs, allowing someone with an injury to walk or move again. As the technology advances, who knows what else they could allow us to do.

Despite the benefits, neural implants come with risks. The most common way of inserting probes into people’s brains is by drilling holes into the skull to serve as a pathway for electrodes. If things go wrong, patients can develop infections, or even bleed in the brain. 

“A high-profile array may touch the skull and damage the tissue when relative micromotions occur between brain and the probes,“ researcher Ming-Yuan Cheng told Phys.org. 

To solve this issue, Cheng and his team made the probe array as thin as possible, employing “innovative microassembly” techniques to limit the height of the array to within 750 micrometers, or about 75 percent of a single millimeter. The probe array is implanted in the brain’s subarachnoid space, 1-2.5 millimeter a cavity in the brain between the arachnoid mater and the pia mater of the meninges. 

These are layers of the membranes that surround and protect the brain and spinal cord. Basically, the implants sit right in the middle of our brain’s protective membranes.

Biocompatibility tests conducted with the neural probes have shown that it did not cause cell membranes to rupture nor suppressed cell growth, both of which would be bad. The team will make design tweaks to make the probes fully implantable. 

If there was ever a justification needed for space technology, it’s that it keeps people like me from constantly being lost. These days, my smart phone is much better than me at getting around thanks to a fleet of satellites that tells it where it is at all times.

Though not a particularly romantic anniversary, today marks 25 years since the first satellite in the U.S. Global Positioning System launched from Cape Canaveral, beginning the set up for one of the wonders of the modern world. In the two and a half decades since then, GPS has become inextricably embedded into just about everything we own, finding use in cartography, smart phone apps, geotagging and geocaching, disaster relief, and hundreds of other applications, while simultaneously raising privacy concerns.

GPS relies on at least 24 satellites flying 20,000 kilometers overhead in one of six different orbital paths, tracing out what looks like a toy model of an atom. With their solar panels extended, each of these 1-ton satellites is about the same size as a giraffe. At any given moment, each satellite beams out a signal identifying itself and giving its time and location.

Your GPS-enabled phone or car captures that signal and compares the time it was received to the time it was transmitted. A quick calculation involving the speed of light allows the device to figure out the distance to that satellite. If you have your distance to two or three satellites, you can triangulate your position on the Earth. When all the GPS satellites are working, a user always has at least four in view, allowing them to determine things like altitude, speed, and direction.

In order to properly triangulate, GPS requires extremely accurate timekeeping, which is why each satellite carries an atomic clock. The satellites are also some of the most important technology using lessons learned from Einstein, who taught us that clocks outside a gravitational well will run faster than those inside of it because of the warping of space-time. An opposite effect comes from the fact that GPS satellites move at 14,000 kilometers per hour (0.001 percent the speed of light), meaning that they experience a slight time dilation making their clocks run slow relative to one at rest on the ground. The two effects taken together mean that the clock on a GPS satellite runs about 38 microseconds faster each day than ones here on Earth. GPS requires accuracy of 20 to 30 nanoseconds (one microsecond is 1,000 nanoseconds), so both effects are part of the calculation determining how far away each satellite is at any given time.

The idea behind GPS comes from the very beginnings of the Space Race. In 1957, the Soviet’s newly launched Sputnik satellite emitted a characteristic radio beep that could be tuned in to as the object passed overhead. While the rest of the U.S. was freaking out, two scientists at the Applied Physics Laboratory realized they could use those transmissions to pinpoint where the satellite was. As Sputnik approached, its radio signals would get compressed a little, shortening their wavelength, and as it receded, the wavelengths would lengthen. This is known as the Doppler effect and can easily be heard as an ambulance speeds toward you, the pitch of its siren getting higher.

The APL scientists used UNIVAC, one of the first commercial computers in the U.S., to figure out Sputnik’s orbit. A year later, they were asked to do the opposite problem: Find out where someone was on Earth based on the location of an overhead satellite. This was soon taken up by the Department of Defense’s Advanced Research Projects Agency (later named DARPA, the agency responsible for developing the internet), which launched satellites starting in 1964 as part of the TRANSIT program, the first satellite navigation program. The U.S. Navy was the main user of the TRANSIT satellites, using them to provide location information for their missile submarines.

Developing, launching, and maintaining the satellites necessary for a full GPS system was horrendously expensive (eventually costing roughly $8 billion in today’s dollars). If it hadn’t been for the Cold War and the fact that the U.S. needed to launch nuclear missiles from anywhere and everywhere, GPS might never have happened. The paranoid U.S. military wanted to make sure they would be able to respond to a Soviet nuclear attack even if some of its nuclear arsenal was destroyed. It wasn’t enough to have aircraft bombers and land-based intercontinental ballistic missile launchers. Submarine-launched ballistic missiles were needed to provide a counterattack from the sea. (The Soviets, of course, had similarly spread-out countermeasures.)

But submarines needed to accurately know their position before launching a missile in order to hit their target. The Navy had TRANSIT for this. Working in parallel throughout the 1960s, the Air Force developed a similar concept called MOSAIC for their bombers and the Army launched satellites under the SECOR program that could determine the location of a unit somewhere on the globe.

By 1973, the branches of the U.S. military realized they could combine their ideas and come up with something superior to all three. In September of that year, the top brass met at the Pentagon and came up with what would eventually become known as the Navigation System Using Timing and Ranging program, called Navstar-GPS, which was later shortened to just GPS. Between 1978 and 1985, the military launched 11 satellites (10 of which worked) to test the new GPS system.

After Korean Air Lines flight 007 was shot down in 1983 for wandering into prohibited U.S.S.R. airspace, President Reagan promised that GPS would be opened up for civilian use on passenger aircraft once it was completed. The first GPS satellite in the modern fleet launched on Feb. 14, 1989. The Air Force had planned to use the space shuttle for this launch in 1986 but was delayed by the Challenger disaster and eventually used a Delta II rocket. The full GPS fleet was completed in 1994 and now at least 32 satellites are in orbit to provide redundancy. During the same time, the Russians developed and launched GLONASS, which works on principles similar to GPS, and is currently the only alternative location-finding system in the world.

At its beginning, the U.S. military feared that GPS technology would be used by enemies, and purposely degraded civilian information so that it could only provide accurate location information to within 100 meters. In 2000, President Clinton had this feature turned off and now civilian devices are usually accurate to within 5 to 10 meters. The European Union and China are currently building their own global navigation systems, known as Galileo and Beidou, respectively, that will serve as further alternatives to GPS in the coming decade. It seems likely that folks in the future will never have to worry about being lost again.

The Sheerwind wind turbine promises to produce 6 times the electrical power than traditional wind turbines.

This funny looking wind tower acts like a funnel, directing the wind from any angle, down through a tube to a ground based turbine generator. The funneling of the wind through a narrow passage effectively creates a “jet effect” increasing the velocity of the wind, while lowering the pressure. This is called the Venturi Effect. This speeds up the wind turbine mounted inside the narrowest portion and generates electricity.

As such it can capture and generate electricity at a much lower wind speed than current wind power technologies.

The idea is so simple, so elegant, and promises to produce so much more energy at lower cost and more efficiently, that it might just be the answer to many problems with current wind turbine technology. Aside from the lower capital investment to get started, and increased efficiency and power generation, it also might be a solution to the ever growing problem of birds (and bats) being killed by traditional wind farms. (Yes, that is a problem)

This technology is not really new in the science of fluid dynamics, however this is a new way to generate electricity, and if successful, promises to grow the wind energy in a more eco-friendly way than ever thought possible.

Imagine a smaller HOME version on your off grid cabin. Now THAT is cool off grid tech!

Venturi Effect Animation: http://en.wikipedia.org/wiki/File:Venturi.gif

via: http://sheerwind.com/technology/how-does-it-work

via: Sheerwind

SOUTH KOREA likes to think of itself as a world leader when it comes to the internet. It boasts the world’s swiftest average broadband speeds (of around 22 megabits per second). Last month the government announced that it will upgrade the country's wireless network to 5G by 2020, making downloads about 1,000 times speedier than they are now. Rates of internet penetration are among the highest in the world. There is a thriving startup community (Cyworld, rolled out five years before Mark Zuckerberg launched Facebook, was the most popular social network in South Korea for a decade) and the country leads the world in video games as spectator sports. Yet in other ways the futuristic country is stuck in the dark ages. Last year Freedom House, an American NGO, ranked South Korea’s internet as only “partly free”. Reporters without Borders has placed it on a list of countries “under surveillance”, alongside Egypt, Thailand and Russia, in its report on “Enemies of the Internet”. Is forward-looking South Korea actually rather backward?

Every week portions of the Korean web are taken down by government censors. Last year about 23,000 Korean webpages were deleted, and another 63,000 blocked, at the request of the Korea Communications Standards Commission (KCSC), a nominally independent (but mainly government-appointed) public body. In 2009 the KCSC had made just 4,500 requests for deletion. Its filtering chiefly targets pornography, prostitution and gambling, all of which are illegal in South Korea. But more wholesome pursuits are also restricted: online gaming is banned between midnight and 6am for under-16s (users must input their government-issued ID numbers to prove their age). Sites from North Korea, including its state newspaper, news agency and Twitter feed, are blocked, as are those of North Korea's sympathisers. A law dating back to the Korean war forbids South Korean maps from being taken out of the country. Because North and South are technically still at war, the law has been expanded to include electronic mapping data—which means that Google, for instance, cannot process South Korean mapping data on its servers and therefore cannot offer driving directions inside the country. In 2010 the UN determined that the KCSC “essentially operates as a censorship body”.

Some Koreans are resisting. In 2011 Park Kyung-sin, a dissenting commissioner, posted a picture of Gustave Courbet’s “L’Origine du monde” on his blog, in protest at the KCSC’s order to block a picture of a man’s genitals—like that found in a science textbook—that he had previously posted on the same blog. He was convicted and fined, though the charges were later lifted. In 2012 a 15-year-old Korean cyber-game champion was locked out of a game of "Starcraft II" while playing after midnight in a competition that was taking place during the day in France. (By the time he reconnected, by entering the details of a parent’s ID card, he had lost the match.) The watchdog has no sense of humour: in 2012 a photographer received a suspended ten-month prison term for retweeting a series of North Korean propaganda posts, likening his inheritance of his father's studio to the North’s leadership transition. Park Dae-sung, a blogger who posted prophecies on the collapse of Lehman Brothers and the crash of the won in 2008 under the pen name of Minerva, spent 104 days in prison for “spreading false rumours”.

Critics spy political interference. In 2004 internet users were required to input their names and ID numbers on political comments in the run-up to an election. In 2009 those posting any comments on websites with over 100,000 daily visitors were required to do the same. That law has since been rescinded. But although the government is beginning to ease some restrictions, it is stepping up its monitoring of social media. The KCSC set up a special sub-committee on social media in 2011, and the following year asked for 4,500 comments on Twitter, Facebook and the like to be removed—13 times more than in 2010. Last year the number of comments deleted increased again, to 6,400. Some officials seem to enjoy posting rogue comments as well as deleting genuine ones. A group of intelligence agents are now under investigation for allegedly posting thousands of messages under false identities in support of Park Geun-hye, now South Korea’s president, in the run-up to the 2012 election. (There is no evidence that Ms Park had ordered this.) In December she said that the government needed to “correct the wild rumours spreading through social network services”, referring to public outcry at the privatisation of railways and health care. South Koreans may enjoy unusually speedy internet connections, but they are not allowed to use them freely.