700 million light years

On August 6, 2019, the US Newsweek website reported that scientists found a supermassive black hole with a mass of 40 billion times that of the Sun in a cluster of 700 million light years away from the Earth. If it is finally confirmed, it will be the largest supermassive black hole in a region with a radius of 1 billion light years.

The researchers said: “This is the largest mass black hole directly detected in the local universe. Considering the nature of the galaxies in which it is located, this is 4 to 9 times larger than expected, and it may be caused by two cores. The elliptical galaxies that have been exhausted are merged.”

Marz Mezqua, the author of the research paper and the Institute of Space Science in Spain, said: “The black holes we found are much larger than expected. It is so huge because it is natural, or because of certain conditions. It’s been so big in a billion years, and we don’t know it yet.” The study was published in the journal Astrophysics.

7 kg
Recently, an international paleontologist group discovered an ancient parrot fossil weighing 7 kilograms, which weighs twice as much as the heaviest known parrot, the cockatoo (called “kakapo” by New Zealanders).

This giant parrot named Hercules lived in New Zealand (Miocene) 19 million years ago. This parrot is about 1 meter high and weighs about 7 kilograms. Like the cockatoo parrot, it is also a member of an ancient New Zealand parrot group that looks more primitive than the parrots that are now breeding in Australia and other continents. “New Zealand is known for its giant birds,” said Dr. Trevor Worthy, a paleontologist at Flinders University. “But no one has found an extinct giant parrot anywhere.”

University of New South Wales professor Mike Archer said: “‘Hercules is the largest parrot in history, and there is no doubt that its huge parrot mouth can swallow anything it wants to eat, so its The type of food is likely to be more than the traditional parrot food variety, and may even be other parrots.” The study was published in the journal Biology Express.

On July 25, 2019, an asteroid about 100 meters long passed by the earth. The nearest distance was about 70,000 kilometers, which is about 1/5 of the distance between the earth and the moon. This asteroid is called “2019 OK”. It was only discovered by astronomers until the day before it was close to Earth. Of course, now “2019 OK” will not pose any threat to the earth. But if it collides with the Earth, its power is enough to destroy a city.

Originally, “2019 OK” was visible at night, and as it approached the Earth, it was observed with a regular binocular to move slowly in the sky. But three days before the Earth, the brightness of this asteroid suddenly decayed to one thousandth, and the difficulty of observation became very large. In fact, before becoming a near-Earth asteroid, “2019 OK” was photographed by other telescopes, but it was obvious that people had not noticed its importance at that time. But these early images did help astronomers determine the orbit of the asteroid. The “2019 OK” runs on a highly elliptical orbit with a revolution period of about 2.7 years and will not approach the Earth again for at least 200 years

The feather structure of modern birds is very complicated, and it is divided into many structures such as feather shaft, feather branch and feather branch. Fossils show that many dinosaurs have only simple hairy feathers, and these simple feathers only provide insulation.

“The first complex feather appeared on a small raptor dinosaur that glides like a squirrel on a prehistoric treetop.” The lead author of the study, Scott Browns, a researcher at the Metz Brown Museum of Natural History. Dr. said, “We studied how dinosaurs evolved from simple insulation feathers to feathers that can be used for gliding.” His team found that during the evolution, the feathers of dinosaurs gradually became larger, stronger, and flatter. Like a gorgeous fan, it grows on the dinosaur’s arms and tail, mainly for swinging courtship, which plays a big role in the evolution of birds. This study provides new clues to the evolution of dinosaurs to birds, but there are still many mysteries in the study of fossil feathers in paleontology. The study was published in the journal Evolution.

A recent study published in the journal Depression and Anxiety showed that eating chocolate, especially dark chocolate, may reduce the clinical manifestations of depression. Chocolate contains many psychoactive ingredients that can excite people. It also contains phenethylamine, a neuromodulator that is thought to be important for regulating mood. But experimental evidence suggests that emotions improve only when chocolate is delicious and enjoyable, suggesting that enjoying the chocolate experience is an important factor, not just a component.

Dr. Sarah Jackson of University College London and her colleagues have conducted a series of studies and surveys and found that people who have eaten dark chocolate in two days have a lower probability of clinical manifestations of depression than those who do not eat chocolate at all. %. Dr. Sarah said: “We still need further research to prove its causal relationship. It may be that depression causes people not to eat chocolate, or there are other factors that make people not eat black chocolate, but they are not easy to be depressed.”

On April 16, 2019, the University of Washington published an experiment in the scientific report of Nature: The three used only the brain to collaborate on a game similar to Tetris. This marks a further step in our communication with ideas.

“Human beings are social animals. We communicate and cooperate to solve problems that cannot be solved by ourselves,” said author Rajesh Rao. “We want to know if a group of people can only use the brain to cooperate, so we This experiment was proposed: two people to help a third person complete the task.”

This game is similar to Tetris, with an irregularly shaped square at the top of the screen and an incomplete bottom line at the bottom. The two “senders” can see the full screen, but they can’t control the box; the “recipient” can only see the square, and its task is to rotate the square to fill the bottom line to complete the game. All three participants are in different rooms and cannot be directly connected to each other. Each “sender” needs to decide whether or not to rotate the box, and then pass the information through the brain to the “recipient” brain via the Internet.

On both sides of the “Sender” screen, buttons with “Yes” and “No” indicate whether the box needs to be rotated, where “Yes” flashes 17 times per second, and “No” flashes 15 times per second. When the “sender” decides whether or not to rotate the square, just focus on the corresponding button, their brainwaves will have fluctuations in the corresponding frequency, and then the inductive helmet worn on their head will convert it into the corresponding The signal is passed to the “recipient”.

“On the receiver side, we placed a racket-shaped electrode directly behind the brain and directly stimulated the optic nerve cells through electromagnetic induction.” Co-author Andrea Stocco said: “We are basically ‘spoofing The neurons in the brain make them mistakenly think that the eye has received the light signal. If the received signal is “yes”, the “recipient” will see a bright flash, otherwise nothing will be seen. The receiver can then decide whether to rotate the square in the same way.

On average, the probability that the game can be successfully completed is around 81%. The research team also tested the case of a “savior” in the two “senders”, which caused the computer to randomly change its decision. After several rounds of gameplay, the “recipient” will learn to favor the information conveyed by another “sender”. Although the current experiment is still very simple, the research team hopes that these results will pave the way for future brain-brain interfaces, enabling people to use brain collaboration to solve problems that cannot be solved by themselves.

If you stick something to the wall with a strong glue, you can appreciate the disappointing of the existing adhesives – the adhesion may be good, but it is irreversible. After sticking, you will often find that the position of the paste is a little bit awkward, although the old strip can also be removed from the wall, but after adjusting the position, it basically has no stickiness. Either tolerate the mistake or start a new one with a new one.

Professor Yang Wei from the Department of Materials Science and Engineering and the Department of Chemistry and Biomolecular Engineering at the University of Pennsylvania has experience in turning natural creations into laboratory results. Her research center is dedicated to applying biomimetic properties to design and architecture. “Gecko can repeatedly stick the limbs to the surface of the object. This process is reversible, but the adhesion is very low.” Professor Yang said, “The vacuum suction cup has enough adhesion, but it must carry a heavy vacuum pump.”

Finally, the research team found a solution from the snail’s mucus. The snail’s viscous secretions become rubbery in the case of damp and watery, and then enter the tiny holes on the seemingly smooth attachment surface. When the water is reduced, it will gradually become rigid, thus locking on the attachment surface. Provides strong adhesion. This process can be reversed when the mucus becomes wet again, allowing easy detachment from the surface of the attachment. Based on this principle, they found that a hydrogel made of polyhydroxyethyl methacrylate polymer can achieve the same effect. Future researchers also want to find or design adhesives that respond to changes in pH, specific chemicals, light, heat, or electricity, thereby broadening the potential applications of reversible bonding.

KLM and Delft University of Technology teamed up at the 2019 International Air Transport Association Annual Conference to unveil an innovative aircraft concept called “Flying-V.” This is a V-shaped aircraft, and this different futuristic shape will make the Flying-V lighter and more aerodynamic.

The team of designers said that the new shape will make the aircraft’s fuel consumption 20% less than the current state-of-the-art Airbus A350. Although it is not as long as the A350, it maintains the wingspan, passenger capacity and cargo capacity comparable to the A350. “The Flying-V is smaller than the A350, and its unique design makes it less resistant to flying. This means that Flying-V requires less fuel when the flight distance is the same.” Project leader Dr. Roelof Vos) said. In the current design, the aircraft uses the most fuel-efficient turbofan engine in the existing engine, and the fuel still uses traditional aviation kerosene, but it can quickly adapt to innovations in the field of propulsion systems—for example, switching to an electric turbofan fan engine .

The Flying-V proportional aircraft model and the full-size model inside part of the fuselage will be officially unveiled at the KLM Experience Day on October 100, 2019, when KLM’s 100th anniversary. According to CNN, the complete aircraft is expected to be put into use between 2040 and 2050.