SciTech Briefs

Human infant brain flexibility attributed to neuron movement

A human infant’s brain remains malleable for a few months after birth, and the mass migration of a large group of nerve cells may be the explanation. Before birth, most of the brain’s nerve cells, called neurons, move to the frontal lobe of the brain. As an infant interacts with the world around them, the neurons react and link together, forming circuits that are malleable. This newly discovered mass migration of neurons may explain why the circuits remain so malleable within the first few months.

“In the first six months, that’s kind of [infants’] critical period when they slowly develop their response to [their] environment. They start to engage with emotions,” says Eric Huang, a neuropathologist at the University of California, San Francisco and co-author of the study. “Our results provide a cellular basis for postnatal human brain development and how cognition might be developed.”

When examining slices of postmortem infant brains under an electron microscope, the researchers found a group of cells making migration proteins. To confirm this, they tagged the cells with a virus containing a glowing protein and observed the neurons’ migration through the brain. The research was published in Science.

Source: Science News

Hurricane Matthew travels Caribbean to coastal U.S.

Hurricane Matthew, which began as a tropical cyclone and transformed into the first Category 5 Atlantic hurricane since 2007, is now making its way up the southeast coast of the United States. Hurricane Matthew originated on Sept. 22 from a tropical wave off Africa and developed into a tropical storm a week later.

On Sept. 29, it became classified as a hurricane, reaching peak strength as a Category 5 the next day. The hurricane made landfall in Haiti and Cuba on Oct. 4 as a Category 4 hurricane.

The storm has killed hundreds of people in the Caribbean Islands, including Haiti, Jamaica, The Bahamas, Cuba, and Dominican Republic. Hurricane Matthew made landfall near Florida on Oct. 7. So far, at least six people in Florida have died, with over 2 million urged to evacuate. The storm is currently making landfall in South Carolina as a Category 1 hurricane after having passed through Florida and Georgia. Serious concerns include flooding. “It’s not just about the beaches. It’s (also) inland where we can have loss of life,” said North Carolina Gov. Pat McCrory during a Saturday morning news conference. As of Sunday morning, the death toll in North Carolina has risen to seven.

Source: CNN

Gecko’s adhesive pads hold key to rapid evolution

Researchers lead by Timothy Higham, an associate professor of biology at the University of California, Riverside, have studied a species of gecko that may explain where a gecko’s adhesive toe and finger pads evolved from. The researchers were examining a genus of dwarf gecko when they came across Gonatodes humeralis in South America. They found that the gecko had microscopic hairs, called setae, underneath its toes, giving it the ability to cling to smooth surfaces, unlike other Gonatodes geckos that rely on complex toe structure.

“In the lab, this gecko can climb smooth vertical surfaces using its incipient adhesive system,” Higham said. This is made possible through the attractive van der Waals forces between the setae and the surface. “The relatively simple adhesive system of the G. humeralis is indicative that slight modifications in form can dramatically influence functional outcomes and the ecological niches that can be exploited.” The research also indicates that the adhesiveness of geckos occurred gradually, suggesting that subtle morphological changes can result in rapid evolution.

The results of the study were published in the Biological Journal of the Linnean Society.

Source: Science Daily

Theory that ancient Earth warmed through methane incorrect

About a billion years ago, our sun was 10-15 percent dimmer than it is today — not enough to warm a planet for the microscopic bacteria developing in the ocean. Atmospheric scientists believed it was the greenhouse gas methane, which traps heat 34 times better than carbon dioxide, that kept enough heat trapped in the atmosphere to keep oceans liquid instead of freezing over.

However, a new modeling study from the Alternative Earths team of the NASA Astrobiology Institute has a different idea. “A proper accounting of biogeochemical cycles in the oceans reveals that methane has a much more powerful foe than oxygen,” said Stephanie Olson, a member of the Alternative Earths team and lead author of the new study. “You can’t get significant methane out of the ocean once there is sulfate.” It is hypothesized that sulfate first appeared after oxygen was introduced into the atmosphere, triggering oxidative weathering of rocks. Sulfate not only limits the production of methane, but it also destroys it directly. Now scientists must revisit what gas could have the same effect.

The study was published in the Proceedings of the National Academy of Sciences.

Source: Science Daily

New, prehistoric shark related to Megaladon found

Scientists have discovered a new species of prehistoric shark that poses more questions than it answers in regards to relating prehistoric sharks to modern ones. This shark is presumed to be over 20 million years old and believed to have grown 12 feet in length, which is still smaller than our own great white shark.The shark, called Megalolamna paradoxodon, is a descendent of Megalodon, an ancient shark that grew to around 60 feet. However, 45 million years separate the two, leaving a large gap of time in the fossilization record.

Scientists have found fossilized teeth of Paradoxodon on the east and west coast of North America, the coast of Japan, and in South America. Although the fossilized teeth bare some resemblance to the teeth of modern sharks, such as the salmon shark, the relationship is unlikely. Scientists have determined that Paradoxodon belongs to the Otodus genus of sharks. Megalodon had previously been classified in the Carcharocles genus, but this is the first concrete evidence to suggest this might not be the case.

The findings were published in the journal Historical Biology.

Source: Popular Mechanics

Facebook Messenger app gets encryption

One of Facebook’s distinguishing features is its private messaging app, Facebook Messenger. Recently, Facebook has introduced “Secret Conversation” to all 900 million Facebook Messenger users. Although messages were already secure, Secret Conversation ensures that messages can be encrypted from one device to another, with not even Facebook or law enforcement and intelligence agencies monitoring them.

When a user first receives an encrypted conversation on Facebook Messeger, a description states, “Your messages are already secure, but secret conversations are encrypted from one device to another. You can choose to make these messages disappear, and you can still report conversations even after a short time after the messages have disappeared.”

Facebook Messenger is only one of the most recent apps utilizing encryption to increase the security of messages while also mandating that the new layer of encryption must be mannually enabled for each conversation; others include WhatsApp and the Signal app.

Source: WIRED