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Black Hole in the Flesh


“We have seen the gates of hell at the end of space and time,” said astrophysicist Heino Falcke of Radboud University in Nijmegen, the Netherlands, at a press conference in Brussels. “What you’re looking at is a ring of fire created by the deformation of space-time. Light goes around, and looks like a circle."

Nearly a century ago, German physicist Karl Schwarzschild came up with a solution for Einstein’s equations in general relativity and suggested that within a certain distance of an infinitesimal point of mass, gravity should be so strong it would stop anything from escaping; in other word, black holes should exist. Since then, astronomers have found binary systems, such as Cygnus X-1, where a star orbits an unseen, denser object that resembles a black hole, but scientists haven’t been able to directly detect the existence of black hole. One of the biggest challenge was the event horizon of the black hole, a surface beyond which gravity is so strong that nothing that crosses it, even light, can ever climb back out.
 
But the holes can nevertheless be seen. As they consume matter that strays too close, they squeeze it into a superheated disk of glowing gas. This is finally observed by the Event Horizon Telescope (EHT) by coopting most of the millimeter-wave telescopes worldwide and combining their data. The telescopes they used stretched from Hawaii to Arizona, Mexico to Spain, and Chile to the South Pole.
 
The black hole captured, known us the M87*, lies at the heart of the galaxy Messier 87. It’s 55 million light years away from us and has 6.5 billion times the mass of our sun. Yet its event horizon is only 40 billion kilometers across—about four times the diameter of Neptune’s orbit. That’s one of the reason why the black hole was so hard to observe; it is the equivalent of resolving the shape of a doughnut on the Moon.
 
Nevertheless, the feat of photographing the black hole is achieved. Now scientists are already moving on and turning their attention to the Sagittarius A*, the black hole that is in the center of our Milky Way. Because Sagittarius A* is nearly 1,000 times smaller than the M87 black hole, matter orbited it many times during each observing session, producing a rapidly changing signal rather than a steady one, says Luciano Rezzolla, a theoretical astrophysicist at the Goethe University Frankfurt in Germany and a member of the EHT team. That makes the data more complicated to interpret, but also potentially richer in information.
 

Science called out on Twitter by Dan Singleton

 
Last week, #ChemTweets celebrity, Prof. and Chair Dan Singleton at Texas A&M called out an obvious mechanistic mistake of a paper published on Science
Any people who know basic orgo would recognize that primary cation is unstable to act as an electrophile. So how did editors and reviewers for Science, reporters at C&EN who highlighted the work, scientists who applauded the discovery, and everyone who read the paper and the reports totally ignore the mistake? The paper wouldn't be on Science if it didn't propose this mechanism as a major advance in chemistry. But the major "advance" here is denying our basic understanding of chemical structure.

"So how is it that Science published something that is fully the organic chemistry equivalent of a flat earth? It must have received great reviews. Dear Reviewers: what were you thinking? Dear Editor: If this had come to me back when I was an editor for JOC, I would have absolutely positively rejected it without review. But then, I am an organic chemist so I guess that helps. [...] At a basic level, the paper reports a mechanism that would be unacceptable in any undergraduate organic course. Although the paper’s reaction happens whatever the mechanism, it should be clear that the mechanism was key to its publication. The mechanism is emphasized in the paper’s title, in the heart of the paper, and in every commentary. This is as it had to be to get published in Science and get press, and I could imagine it affecting patent rights. That is because the same reaction could already be accomplished by a free radical mechanism. The new conditions and catalyst appear to be more efficient, but optimized efficiency alone does not get you patents and does not get you into Science. The paper needed the impossible mechanism."

I think here is a good place to talk about the fetish toward high-impact journals in science. Science needs to have places for highly influential works, but just being on a high-impact journal does not justify the paper in any way. In fact, high-impact journals have higher retraction rates. Too often researchers want their paper to raise eyebrows so they make a lot of false assumptions and push things too far. This is not to say that science should not strive to develop as fast as possible. This is about pushing the boundary forward in a scholarly way. A good scientist should try their best to be confident of the result and rigorous with the logic. A study is valuable because it does fantastic science, not because it's on a top-notch journal or has some famous name on it. We need to fight the imperfection of science by being critical with every paper we read and reading from a wide range of journals, not just the well-known brands.

It's time to ask yourself: if you read the paper without knowing this, will you notice the mistake and call it BS? Or will you just be amazed by the mechanism because it's on the trustworthy Science? That's what distinguishes good scientists from normal ones. 

This singing mouse’s brain could reveal keys to snappy conversation, Science


Human conversations are extremely complicated, not just because we are able to carefully plan our words and adjust them on the fly, but also because we need to direct our vocal muscles to spit them out at socially appropriate moments. In human conversation, it normally takes 200 milliseconds on average for a person to respond in a conversation. However, most of the lab mouse used today lack this vital skill. They are able to do a little singing, but the songs are relatively disorganized and unpredictable, and moreover, they never take turns when singing.
 
Recently, experiments on a different type of singing mouse, Alston’s singing mouse, changed the whole story. Each of the Alston’s singing mouse has its own repertoire, and “We can recognize this one particular song and say, ‘Ah, that’s Ralph.’” says Michael Long, a neuroscientist at the New York University School of Medicine in New York City. What is even more amazing about this kind of mouse, is that it takes turn singing. When a male mouse enters a chamber adjacent to another male and can hear its neighbor sing, it precisely times its own songs to avoid overlap with the neighbor; it starts about half a second after the other mouse finishes. The mouse with a neighbor also sings four times as much as when it is alone, the researchers found.
 
Many studies have shown that animal vocalizations originate in deep, evolutionarily ancient parts of the brain—so-called subcortical structures. But in this study, researchers revealed that there is also a separate structure in a higher region called the motor cortex acted like an orchestra conductor, turning the songs on and off based on social cues. The researchers first identified the orofacial motor cortex (OMC) that, when stimulated, caused the mouse to flex its vocal muscles. When they put a cooling device over that region to slow down its neural activity, the mouse took longer to reach the end of its song. Then the scientists gave the mouse a drug that completely inactivated the OMC—the vocalizations were evidently produced elsewhere in the brain, and observed in the mouse that hearing another mouse’s song no longer increased their own singing.
 
Alston’s singing mouse is “a new, potentially interesting model for vocal communication,” says Karel Svoboda, a neuroscientist at the Howard Hughes Medical Institute's Janelia Research Campus in Ashburn, Virginia. Still, he says, “We need to know a lot more.” Furthermore, exploring the speaking mechanism of this mouse could potentially provide insights into preventing autism, a disorder that can limit a person’s ability to communicate.

Neotropical singing mice (Science Magazine)
New human species found in the Philippines
Quote of the week: If you see a bald eagle in the zoo, you are actually seeing the symbol of freedom in captivity.
ISP Sci. Rev. 15 (2019)
Editor: Shiwei Wang, Rossoneri Jing
Integrated Science Program
Northwestern University






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