Scientists make new find in photos of freakish shark

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  A giant deep-sea isopod or Bathynomus giganteus.REUTERS

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Researchers studying photos of a rare goblin shark hauled up in the Gulf of Mexico last month say they've spotted something just as exciting—and just as weird-looking—in the shrimpers' catch.

Mixed in with the shrimp are unusually large numbers of giant isopods, a deep-sea creature that resembles a cat-sized woodlouse, reports the Houston Chronicle, which has a photo gallery of the catch.

Scientists believe their presence, along with that of the goblin shark, indicates that the trawler passed over a "whalefall"—a decaying whale on the ocean floor, perhaps as much as a mile below the surface.

Entire ecosystems can spring up around the dead whales, living off the carcass for decades. "While I think (the) goblin shark is cool and all, look at all those freakin' giant isopods!" tweeted marine biologist Andrew Thaler, who plans to seek funding to send a submersible to the site.

If his team makes it there, they may encounter the same goblin shark: The captain who caught it says he returned the strangest creature he's encountered in his 50 years of shrimping to the Gulf after taking photos.

"Anything that's alive we try to put back in the ocean," he tells CNN

Human brain microchip is 9,000 times faster than a PC

Despite advances in computing, today's computers remain far less efficient than the 3-lb. hunk of matter in our skulls. But a new microchip modeled on the human brain is much faster and more efficient than a typical computer, researchers report.

The microchip called "Neurogrid" could open up windows into understanding the human brain and developing new forms of computing patterned after brain circuits. Researchers are now investigating how these chips could be used to control prosthetic limbs.

"From a pure energy perspective, the brain is hard to match," Kwabena Boahen, the bioengineer at Stanford University who led the chip's development, said in a statement. Not only are personal computers slower, they take 40,000 times more power than the brain to run, Boahen said. 

Neurogrid consists of 16 custom-designed Neurocore chips in a device the size of an iPad, which can simulate 1 million neurons and billions of synapses, or brain connections. That's a vast improvement over previous brain simulations, but still only a fraction of the roughly 80 billion neurons in a human brain, researchers said.

Neurogrid uses about 9,000 times less power than a typical PC, by having synapses share hardware circuits, and about the same amount of power as a tablet.

In addition to modeling the human brain, Boahen is working with other Stanford researchers to adapt Neurogrid for controlling prosthetic limbs for paralyzed people. The chip would translate brain signals into movements of the limb, without overheating the brain. Another possible application is using Neurogrid to control humanoid robots.

Currently, programming the chip requires an understanding of how the brain works. But Boahen wants to create a "neurocompiler" that would let engineers and computer scientists with no neuroscience knowledge to program Neurogrid.

The Stanford team's work is just one of many efforts to model the human brain using computers. The European Union'sHuman Brain Project aims to simulate a human brain on a supercomputer. The U.S. BRAIN Initiative (short for Brain Research through Advancing Innovative Neurotechnologies) takes a more general approach, developing new tools for measuring neuron and brain circuit activity.

IBM's SyNAPSE project (short for Systems of Neuromorphic Adaptive Plastic Scalable Electronics) aims to design chips, called Golden Gate chips, modeled after the vast number of connections among neurons in the brain that help it solve problems efficiently. Each Golden Gate chip consists of 256 digital neurons with 1,024 digital synapses each, and the company plans to increase these numbers.

Germany's Heidelberg University has its BrainScales project, which aims to create analog chips that mimic neurons and synapses that could model drug interactions at a faster rate than currently possible. Researchers have developed the HICANN chip (short for High Input Count Analog Neural Network), which can simulate 512 neurons with 224 synapses each, which they also plan to expand soon.

These various efforts have made different trade-offs in capability and performance, but Neurogrid was the most cost-effective, Boahen said.

The prototype Neurogrid chip cost about $40,000 to make, but researchers hope to cut the cost 100-fold using modern manufacturing techniques. Even so, modeling the human brain at the same energy efficiency remains a major challenge, according to researchers.

Sex after a heart attack: Is it safe?

For most patients, having a heart attack can be a frightening, life-changing experience.  Many heart attack survivors are reluctant to engage in any physical activity in the days and weeks following their event.  However, it is essential that patients begin to resume normal activity in order to manage risk factors and avoid developing a sedentary lifestyle.  Avoidance behaviors, while common in heart attack survivors, may lead to anxiety and depression, and can actually hamper recovery.

As a general rule, if you can climb one flight of steps without developing chest pain or shortness of breath, you are ready to resume sexual activity.   Most patients can resume intercourse within a week of a major cardiac event.  However, there are a few other factors to consider when developing a timetable for safely resuming sex.

Some heart attack patients most undergo some type of procedure to restore blood flow to the heart.  The type of procedure used to restore blood flow will play a role in determining when it is safe to resume sexual activity.  

If a patient has a catheter-based stenting procedure (where a small metal tube is inserted into a heart artery through a puncture site in the groin or arm) sexual activity may be resumed as soon as the site heals—usually within a week or so.  If an open-heart procedure such as bypass surgery is required, the patient will need to wait 6-8 weeks in order to allow the wounds in the breastbone to heal properly.  

Some patients recovering from heart attacks may be on medicines that can worsen conditions like erectile dysfunction (ED).  In addition, many men with heart disease also have ED.  For men who wish to take medication for ED, it is essential to discuss all of your medicines with your physician.  If you are taking nitrates to treat chest pain, it is not safe to use medications for ED.  

While most patients worry about the safety of having sex after suffering a heart attack, the reality is that only 1 percent of all heart attacks occur during intercourse.  In fact, the risk for having a heart attack during sex is the same for men whether or not they have coronary artery disease at all.  

Having a sedentary lifestyle increases the risk slightly, but having sex regularly decreases the risk for heart attack likely due to an increase in exercise capacity.  In a study conducted by the American Heart Association, only 0.6 to 1.7 percent of heart attack-related deaths occurred during sex, and of these, nearly 75 percent were in men who were involved in extramarital sexual activities in unfamiliar surroundings with younger partners.  

Communication with both your partner and physician plays a key role in recovery and in understanding when it is safe to resume sexual activity.  It is imperative for doctors and patients to feel comfortable discussing sex after heart attack—don’t be embarrassed.  In addition, speaking with your significant other about your fears concerning sex after a cardiac event can be a good way to begin recovery.  

The bottom line is: It is safe to have sex after suffering a heart attack for the majority of patients.  If you develop chest pain or shortness of breath during sexual activity it is important to stop immediately and contact your doctor to discuss your symptoms further.  In addition, if you develop symptoms that do not go away after stopping intercourse, contact 911 immediately and seek evaluation in an emergency room.   

Dr. Kevin Campbell is an assistant professor of medicine in the division of cardiology at University of North Carolina at Chapel Hill. For more from Dr. Campbell, visit his website DrKevinCampbellMD.com.