Thanks to the wonder of 3D printing, scientists have managed to create a real, working heart — out of a patient's own cells.
The heart measures about 2.5 centimeters long, which is around "the size of a rabbit's heart," Bloombergreports. Although it's certainly too small to function as a human heart, it was printed using an ink made from a patient's biological materials, meaning it's an exact match for the patient in question.
A process like this, which converts fatty tissue from the patient into stem cells and the so-called "bio ink," could be used to print tissue to patch diseased hearts, or even replace a heart entirely. Because it's made from each individual patient, the risk of an organ rejection is greatly lessened, said Tal Dvir, a professor at Tel Aviv University who directed the project.
This medical breakthrough was published on Monday in the journal Advanced Science, where it laid out the possibility of "personalized tissues and organs" being custom-printed for patients who need them, rather than those patients relying on organ donors.
While the tiny version of the heart took about three hours to print, it's estimated that a human-sized one could take a full day, and would require many more cells from the patient. But it's worth exploring whether these 3D-printed tissues could practically serve to replace a diseased heart with "something that works," Dvir said.
The coldest place on Earth is really, really cold.
In 2013, scientists pinpointed the lowest temperatures on Earth, in eastern Antarctica close to the South Pole, where the thermometer plunged to an almost inconceivably frigid negative 135 degrees Fahrenheit. But in a new study published in the journal Geophysical Research Letters this week, scientists have proven that it can get even colder.
The study was led by the National Snow and Ice Data Center (NSIDC) at the University of Colorado at Boulder, which analyzed new data from NASA satellites and discovered temperatures as cold as negative 144 degrees Fahrenheit in that same region in Antarctica.
But it's not as simple as that — as it turns out, temperatures that cold start to do funny things to "the limits of thermodynamics," IFL Sciencereported. Even though the open air can be slightly warmer, colder air is heavier and can sink into "pockets" near the surface of the uneven terrain in that area. These "pockets" can only form under very dry conditions, when there's little to no water vapor in the air to trap heat.
The NSIDC plans to place instruments near the South Pole to confirm this study's results, but scientists believe that this may well be the very coldest temperature possible on the surface of the Earth.
It's time to think up another nonsensical combination of capital letters, special symbols, and random numbers.
Twitter announced in a blog post Thursday that a glitch had caused users' passwords to be revealed in plain text in its internal systems. The bug has been fixed, Twitter said, but "out of an abundance of caution" it is recommending that users consider changing their account passwords. "Our investigation shows no indication of breach or misuse by anyone," the company added.
The social network explained that user passwords are obscured from internal view using a tool known as bcrypt, which replaces passwords with random arrangements of numbers and letters. A glitch resulted in the passwords being written in their actual state in an internal log.
"We found this error ourselves," Twitter clarified, and the service has already removed all passwords from its internal logs. Twitter has more than 330 million users worldwide. Read the company's full announcement here. Kimberly Alters