Astrophysicists solved a long-standing mystery about black holes, while researchers discovered that cells don’t even need to leave the body for gene editing to work and found a new protein segment that could be targeted to treat autoimmune diseases. It’s from the macro to the micro and all the way back in this week’s coolest scientific discoveries.
What is it? Gene-editing technology holds great promise as a medical treatment, and now Harvard scientist Amy Wagers has taken the field a big step forward: She’s found that cells don’t have to be removed from the body and placed in a petri dish in order for genes to be modified. That kind of work can be done on-site.
Why does it matter? If you want to make tweaks to a genome — say, to develop a treatment for some forms of muscular dystrophy — you’ve got to start in the stem cells, which are the undifferentiated precursor cells that can grow into many different kinds of cells. And researchers practicing the current state of the art must remove stem cells from a patient’s body, alter them genetically, and then put them back. It’s a delicate process that involves some risk: “When you take stem cells out of the body, you take them out of the very complex environment that nourishes and sustains them, and they kind of go into shock,” Wagers said. “Making genetic changes without having to do that would preserve the regulatory interactions of the cells — that’s what we wanted to do.”
How does it work? Wagers and her colleagues created a “package” for the delivery of stem cells in the body: an adeno-associated virus, or AAV, that doesn’t cause disease but can “deliver gene-editing cargo into several different types of skin, blood, and muscle stem and progenitor cells,” according to the Harvard Gazette. After realizing success in tests on mice, Wagers said that it could have important implications on human therapies quite soon: “AAVs are already being used in the clinic for gene therapy, so things might start to move very quickly in this area.” Wagers’ research is described further in Cell Reports.
In the near future, the lives of military personnel may be saved by an intriguing form of protective gear that can resist armor-piercing projectiles while weighing less than half as much as equivalent models available today.
What is it? At North Carolina State University, researchers designed an armor that can stop armor-piercing .50 caliber rounds as well as typical steel armor does — but weighs less than half as much. They described their findings in the journal Composite Structures.
Why does it matter? Built around a material called composite metal foam, or CMF, the armor could enable designers to create military vehicles that offer just as much protection as those currently deployed but are much more lightweight — and therefore easier to move around and more fuel-efficient. Professor of mechanical and aerospace engineering Afsaneh Rabiei, who invented CMF, said that the materials also “hold promise for a variety of applications: from space exploration to shipping nuclear waste, explosives and hazardous materials, to military and security applications and even cars, buses and trains.”
How does it work? Metal foam is sort of what it sounds like: hollow metallic spheres made of titanium or stainless steel, embedded in a metallic matrix. Sandwiched between a ceramic faceplate and a thin back plate made of aluminum, the CMF armor was tested with ball rounds and armor-piercing rounds that struck at impact velocities of between 500 and 885 meters per second. Rabiei said, “The CMF armor was less than half the weight of the rolled homogeneous steel armor needed to achieve the same level of protection.”
What is it? A team of astrophysicists from Northwestern University, the University of Amsterdam and the University of Oxford created the most-detailed-ever simulation of a black hole, and in the process solved a long-standing mystery that you have no doubt been wondering about: Does the accretion disk align with the black hole’s equator?
Why does it matter? The accretion disk is the assorted matter that orbits and is eventually sucked into a black hole, and physicists have been trying since 1975 to verify an argument posed by physicists John Bardeen and Jacobus Petterson — that “a spinning black hole would cause the inner region of a tilted accretion disk to align with [the] black hole’s equatorial plane,” according to a release from Northwestern. In finding that yes, the disk aligns with the black hole’s equator, the team “brings closure to a problem that has haunted the astrophysics community for more than four decades,” said Northwestern’s Alexander Tchekhovskoy, who co-led the research.
How does it work? Without luminous accretion disks orbiting around black holes, astronomers wouldn’t even be able to see the objects. For that reason they’re a big deal indeed in astrophysics, and also because they affect the growth and rotation speed of black holes — thereby affecting the black holes’ impact on the galaxies that surround them. Tchekhovskoy et al. were able to model the disks with the help of a whole lot of computing power; read more about their methods in Monthly Notices of the Royal Astronomical Society.
What is it? MIT researchers created a “photonic chip” that uses light rather than electricity to power optical neural networks; it also doesn’t require a lot of power.
Why does it matter? At the frontiers of artificial intelligence, neural networks are human-brain-inspired computer systems that use complex AI algorithms to help with tasks like image identification, operating driverless cars and drug development. Optical neural networks can do jobs like these even faster and more efficiently than their electrical counterparts. But for both optical and electrical neural networks, all this computer thinking comes at a cost — as MIT News explains, neural networks also “eat up tons of power.”
How does it work? Neural network processing uses so much power that key players in this arena — including Google and Tesla — “have developed ‘AI accelerators,’ specialized chips that improve the speed and efficiency of training and testing neural networks,” reports MIT News. This is the technology that the new photonic chips improve upon. Whereas today’s AI accelerators are still mostly electrical chips, MIT’s photonic chip can both “reduce power consumption and chip area” and “scale to neural networks several orders of magnitude larger than its counterparts.” The team explained its findings further in Physical Review X.
What is it? A study by researchers at Texas A&M University homed in on a segment of a human protein called STING that might “hold the key to treating autoimmune diseases and cancer.”
Why does it matter? The discovery of the segment and its function could lead other researchers to developing novel treatments for the aforementioned diseases as well as frontotemporal dementia and could also point the way toward a different understanding of autoimmune diseases and their treatment. “It’s a seemingly small discovery in basic research, but one that could have enormous implications regarding the way diseases are treated in the future,” according to a release from Texas A&M.
How does it work? STING stands for “stimulator of interferon genes” — they’re proteins that get the immune system going in the face of things like viral infection. The scientists zeroed in on a small section of proteins that could be targeted in future drug treatments; for instance, they might be suppressed to prevent unwanted autoimmune reactions. Biochemist and biologist Pingwei Li said, “Our immune system is like an electrical circuit. We discovered that this motif of STING is involved in the activation of the TBK1 [a signaling molecule activated during a viral infection], essentially like a switch that turns the immune system on to produce interferons to fight against viral infections or cancer.” The full paper is in Nature.