Quantumaniac

NASA Myth. 

dadavin:

Yes I’m the idiot who spends one hour drawing a nice diagram for a physics prac report. #truth #proud

Exoskeleton Helps Paralyzed Patients to Walk

Ekso Bionics, a California company, developed the Human Universal Load Carrier, or HULC, a military exoskeleton licensed to Lockheed-Martin (at that time the company was known as Berkeley Bionics). Ekso developed another exoskeleton, also called the Ekso, for people who need either physical therapy or rehabilitation. Other exoskeletons have been built for arm movement; this is among the first to help people move their legs and to be commercialized in the United States (another type, called Rex, is available in New Zealand, but it works on different principles).

Amanda Boxtel is one of those people. Her legs were paralyzed after a skiing accident in 1992, at the age of 24. “I never thought I would walk again,” she said today at a press event in New York City. Now she practices walking with the Ekso. Demonstrating it, Boxtel was able to take steps, and even turn around, if slowly. Even though she was assisted by engineer Thomas Dwyer, who controlled it using a small game-controller-like device,it showed the possibilities.

The Ekso is currently used in hospitals and physical therapy centers. Right now it offers more natural movement to people who might need help rebuilding muscles after an injury, or relearning to walk after a stroke. It can’t walk backwards or climb stairs, though.

That will change in future iterations. Within two years, said Mike Magill, sales and marketing consultant to Ekso, there will be a model for the home — slimmer, lighter, and able to move in all the ways that humans ordinarily do. “It should be as easy as putting on a pair of jeans,” he said.

For a person to walk, the Ekso has to look at where their weight is, as well as check how the leg is bent and the location of the other leg. If certain conditions are satisfied, it takes the next step. Dwyer said a person can walk by just shifting her weight. At present the exoskeleton needs to be used with crutches, but as the system is refined, they will become unnecessary, he added.

One thing that’s different from the HULC (see a video here of the Science behind the HULC) is the kind of power the motors use and how much they need. The HULC uses hydraulic systems for extra strength and requires a lot more power. The Ekso uses smaller electric motors and is powered by what is essentially a laptop battery (if a bit more powerful). It doesn’t need to lift hundreds of pounds in addition to the user, so it can be made smaller and slimmer. Eventually, the company also hopes to make one that can be easily taken on and off and is small enough to wear.

Beyond walking, there are also therapeutic benefits. When the legs move circulation is better, and it can help patients who might recover use of their limbs to exercise as part of their therapy.

Boxtel said she can’t wait to get one. One big reason: plane rides. Wheelchair users can’t bring their chairs onto a plane because the aisles are too narrow. So they have to wait for the crew to get them a special chair to get them out. “I don’t know how many times I’ve been left there, forgotten,” she said.

Beyond that, there are therapeutic benefits. Boxtel said when she uses it the circulation in her legs gets better, and with it her overall health. She also likes being able to stand. “For the first time in twenty years, I can see people at their level.”

The First Human Infected by a Computer Virus

Mark Gasson, senior research fellow at the University of Reading, was able to infect a tiny, radio frequency identification (RFID) chip with a virus before he placed it under the skin on his hand. He uses that chip to activate his cell phone, as well as open secure doors.

Thanks to the computer chip, his cell phone knows when he’s using it, and when someone else is trying to operate the device. If someone else tries to use his phone (after, say, stealing it), that person is not able to use it. Only Gasson can.

And instead of him swiping an ID card to enter his building, he just needs to wave his hand to gain entrance. The convenience of not taking out his ID and the safety of his phone come with a price, however.

He served as carrier, and was able to pass the virus on to an external computer. The virus was of Gasson’s own design and was not malicious. But he was able to show that computer viruses can move seamlessly between computers within and outside the body. And theoretically, if a person had several computers in his or her body, a computer virus could spread from one to another, infecting them all. 

Why would people have computers in their bodies? Researchers around the world are developing tiny electronics that can be ingested or embedded in people for health or even security reasons. Consider the camera pill, which records data from the intestines, bionic eyes, bionic limbs, implantable telescopes to improve vision, and more.

The kind of computer chip that Gasson installed in his body is not in wide use, so no need to worry as of yet. In fact, you have more reason to worry about bed bugs than computer bugs. But in the future, computers will get under our skin, and people will have to take precautions to spread digital infections. 

The “Scientifically Perfect” Face 

English scientists think that such a face would mirror Florence Colgate’s. The 18-year-old student recently won a competition to find Britain’s most naturally beautiful face. Although the final test came down to an opinion poll, science backs up Colgate’s perfection, according to the Daily Mail.

Her “flawless proportions” represent the optimum ratio between eyes, mouth, forehead and chin, the newspaper reports. For example, it’s believed that in the most attractive female faces, pupils are just under half the width of the face; Colgate’s ratio is 44 percent. The distance between eyes and mouth should be just over a third of the distance between the hairline and chin; Colgate’s ratio is 32.8 per cent.

Scientists have also linked symmetry and beauty, and Colgate’s face is almost perfectly symmetrical. ”Symmetry appears to be a very important cue to attractiveness,” Carmen Lefèvre, PhD student at the University of St. Andrews’ Perception Lab in the School of Psychology, told KentOnline. “Although we don’t realize it in everyday interactions, in most people’s faces the right and left half of the face are actually quite different. For example, the size of the eyes is different or the nose is slightly bent to one side. An explanation why symmetry is important is that it may be a signal of health and good genes.” The “Lorraine: Naked” competition judged contestants without makeup or plastic surgery.

“I was fine having my picture taken with no make up on as I am used to it,” Colgate told KentOnline. “I hope people will look at me and think they don’t need to wear lots of make up…I am very happy with the way I look. I would never have any plastic surgery or botox.”

England agrees. Her face will be plastered across billboards at Superdrug stores across the country as a result of her victory.

(Source: news.discovery.com)

The Virus That Might Kill Your Computer on July 9th (And How to Stop It!)

It sounds like one of those annoying chain e-mails that show up from technically-challenged acquaintances: “The FBI Will Take Your Computer Offline July 9 If It Has A Virus! Visit This Site Immediately To Check!! Forward This To Everyone You Know!!!”

But the Federal Bureau of Investigation really has posted a warning on its site about the risk of “DNSChanger” malware, which really will result in your computer getting disconnected from the Web on July 9, if you don’t clean it up.

The story began last November when the Bureau announced it had busted a four-year-old Estonia-based conspiracy. The suspects had infected about 4 million computers — some 500,000 in the United States — with malware called DNSChanger (also referred to as Alureon) that diverted victims to scam sites.

This “rootkit” malware was usually delivered as a fake download for Windows or Mac OS X that then silently altered the Domain Name System (DNS) settings on computers and even some wireless routers. That’s about the most serious compromise an Internet-connected machine can suffer; when DNS stops correctly translating domain names like discovery.com to machine-readable Internet Protocol addresses like 63.240.215.85, you no longer know what sites you’re dealing with.

But once an infected machine had been cuffed to DNSChanger’s rogue servers, shutting it off would effectively unplug it from the Internet. To give unaware victims time to clean up their systems, the FBI secured a court order requiring the Internet Systems Consortium, a non-profit Net-architecture firm, to take over and sanitize those servers.

But all bad things must end; after one stay of execution, ISC is now set to turn off the DNSChanger servers on July 9. At that point, any infected machine will only be able to connect to numerical IP addresses, essentially, a rotary-dial version of the Internet.

Early advice on checking for a DNSChanger infection required a fair degree of technical skill, but now you just need to be able to read one line of text or know the difference between green and red. Visit www.dns-ok.us; if you see a green background to the image on that page and the words “DNS Resolution = GREEN,” you’re safe. (Your Internet provider may also offer a similar service; Comcast subscribers, for example, can check their computers at amibotted.comcast.net.)

If you see otherwise, you have a month and change to fix the problem. Since DNSChanger can disable security programs, you may not be able to do this the easy way, by clicking a “scan” button in your anti-virus app. You can try specialized DNSChanger-removal tools from such firms as SecureMac or run general-purpose anti-rootkit software like MalwareBytes’ Anti-Malware or Kaspersky Labs’ TDSSKiller.

The DNS Changer Working Group, created by Internet-security experts to help clean up the problem, has also set up a page with links to manual malware-cleanup instructions from Microsoft and others. In a worst-case scenario, you may need to reinstall your computer’s operating system and software from scratch, using either the discs that came with the computer or the recovery partition on its hard drive. 

But that still beats having a computer that can only navigate the Internet by numbers. So if you have friends or family members online who might not know to check for this problem, please forward this post to them. But hold the exclamation points.

(Source: dailygalaxy.com)

Weird Spiral Features Found on Mars

Strange coiling spiral patterns have been found on Mars surface by a graduate student who was doing what many of us enjoy: looking through the high-resolution images from the HiRISE camera on the Mars Reconnaissance Orbiter. Similar features have been seen on Earth, but this is the first time they have been identified on Mars. However, on Mars, these features, called lava coils, are supersized. “On Mars the largest lava coil is 30 meters across – that’s 100 feet,” said Andrew Ryan from Arizona State University. “That’s bigger than any known lava coils on Earth.”

The lava coils resemble snail or nautilus shells. Ryan has found about 269 of these lava coils just in one region on Mars, Cerberus Palus. 174 of them swirl in a clockwise-in orientation, 43 are counterclockwise, and 52 of the features remain unclassified due to resolution limits.

On Earth, lava coils can be found on the Big Island of Hawaii, mainly on the surface of ropey pahoehoe lava flows. They usually form along slow-moving shear zones in a flow; for example, along the margins of a small channel, and the direction of the flow can be determined from a lava coil.

Math peeps - do you see any relation to a Fibonacci spiral? I’m interested to see how this possible connection might be handled. 

Read more. 

How Much Does Fire Weigh? 

Question: Since fire is a plasma, and plasma is a state of matter, and matter is defined as anything that has mass, would that then mean that fire has mass and weight to it? If so, is there a way to measure its weight? How much space would, say, a pound of fire take up?

Answer: It weighs more than nothing, but if you’re at the bottom of a pillar of fire, being crushed should be your second concern

Fires, putting aside details about plasma and chemicals or whatever, is just hot air.  For a given pressure the ideal gas law says that the density of a gas is inversely proportional to temperature, in Kelvin.  You can use this fact, the temperature and density of air (300°K 1.3 kg/m³), and the temperature of your average run-of-the-mill open flame (about 1300°K) to find the density of fire. For most “everyday” fires, the density of the gas in the flame will be about 1/4 the density of air.  So, since air (at sea level) weighs about 1.3 kg per cubic meter (1.3 grams per liter), fire weighs about 0.3 kg per cubic meter.

One pound of ordinary fire, here on Earth near sea level, would take up a cube about 1.2 meters to a side.  The reason that fires always flow upward is that its density is lower than air.  So, fire rises in air for the same reason that bubbles rise in water: it’s buoyant.  Enterprising individuals sometimes even take advantage of that fact.

If you were on a planet with no air at all, fire would fall to the ground instead of rise because, like all matter, it’s pulled by gravity.  Also, it would be hard to keep the fire going (what with there being no air).

(Source: askamathematician.com)