Science, Skepticism, & Social Justice links

Man sets a new world record by diving more than 1000 feet

Diving off the coast of Dahab, Egypt, Gabr reached a depth of 1,090 feet 4 inches (332.35 meters). The previous record holder for the deepest scuba dive, Nuno Gomes of South Africa, also dove off the coast of Dahab, in 2005, reaching a depth of 1,044 feet (318.21 m).

To put these depths into perspective, three American football fields laid end to end would measure 900 feet (274.32 m) long — less than the distance these divers reached underwater. Most recreational scuba divers only dive as deep as 130 feet (40 meters), according to the Professional Association of Diving Instructors.

It took Gabr only about 12 minutes to reach the record depth, which he achieved with the help of a specially tagged rope that he pulled along with him from the surface, Guinness World Records officials said in a statement. However, the trip back up to the surface took much longer — about 15 hours. Returning too quickly from such depths is associated with a number of health risks, such as decompression sickness (also known as the bends) and nitrogen narcosis from excess nitrogen in the brain, which Gabr luckily avoided.

15 hours to return to the surface? I wonder if he got bored with all that waiting.

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Paralyzed rats walk with spinal cord stimulation

Spinal cord injury is one of the leading causes of paralysis in the US, and the outlook for the vast majority of patients is depressingly bleak. The spinal cord is essential for movement because it acts as a middle man between the brain and the rest of the body; when it is injured, the flow of information to other body parts can be disrupted, resulting in the inability to move some or all limbs. Unfortunately, there is no effective treatment, so for many the paralysis is permanent.

But recently, there have been some encouraging developments in treatment as scientists figured out a way to mimic the brain signals required for movement by directly stimulating the spinal cord with electrical pulses. Remarkably, this experimental therapy allowed four paraplegic men to regain some voluntary movement in their hips, ankles and toes.

The problem with this technique, which is known as epidural electrical stimulation (EES), is that the amplitude and frequency of electrical pulses need to be constantly adjusted, which is difficult to achieve while an individual is attempting to walk. To overcome this limitation, EPFL researchers have developed algorithms that automatically adjust the pulses in real-time during locomotion, dramatically improving the control of movement.

For the study, the researchers used paralyzed rats whose spinal cords were completely severed. They surgically implanted electrodes into their spines and then placed them on a treadmill, supporting them with a robotic harness. After testing out different pulses and monitoring walking patterns, the researchers discovered that there was a relationship between how high the rat lifted its limbs and pulse frequency. Using this information, the researchers were able to develop an algorithm that constantly monitored the rats’ movement. This data was then fed back into the system which allowed automatic, rapid adjustments in the stimulation in real time, mimicking the way that neurons fire naturally.

The rats were able to walk 1,000 steps without failure and were even able to climb staircases. “We have complete control of the rat’s hind legs,” EPFL neuroscientist Grégoire Courtine said in a news release. “The rat has no voluntary control of its limbs, but the severed spinal cord can be reactivated and stimulated to perform natural walking.”

If they can successfully adapt this for use on humans, this could benefit so many people.  Science-continuing to advance understanding and making lives better.

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Bob Carroll of The Skeptic’s Dictionary asks a few questions in an entry on Political Skepticism

Most skeptics don’t do politics unless religion is involved. Some don’t do religion unless politics is involved. Most skeptics, however, whether they do politics or religion, claim to be involved in some sort of consumer protection. They have no problem with criticizing and debunking various so-called alternative health practices. People are risking their lives and wasting their money on treatments that provide false hope at worst and some sort of placebo effect at best. Most skeptics have no problem with criticizing and debunking pseudoscientific ideas such as perpetual motion machines, free energy claims, and junk science programs that promise to unleash all that potential you have in your brain, your heart, or your body. People are wasting their time and their money on programs and devices that have no plausible scientific support. Most skeptics have no problem criticizing and debunking people who claim to be psychic. People are being emotionally manipulated at great expense by those who claim to get messages from the dead or see into the future. So why–when people are being manipulated, robbed, or physically and emotionally abused by those cloaked in the authority of religion or the state–do some skeptics balk at going there to criticize and debunk? One answer is tradition: skeptics have traditionally focused on exposing psychic fraud, paranormal mischief, and pseudoscientific quackery. In any case, there are only a few prominent skeptics who stay away from anything to do with religion, but most still do not spend much time scrutinizing the political scene for deception, fraud, abuse, unethical extortion of money, and lies that do much more damage to us than all the psychics, supplement pushers, cancer quacks, detoxers, and promoters of brain-enhancing exercises put together.

[…]

Where are the skeptics questioning the long-term effects of creating a nationwide militarized network of local police departments that not only monitor our every move, but are prepared to turn against our own citizens? What kind of Homeland Security is that? Add to all this the federal government’s monitoring of phone conversations that have nothing to do with national security or terrorism and what do you have? A recipe for a very dark future, all begun under the guise of protecting us from foreign enemies–those terrorists who “hate our freedom.

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Police Militarization Infographic

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