A new breakthrough in actives! Physicists drive new developments in next-generation shape-shifting robots

A team of physicists from the University of Bath in the UK recently published in the international scientific journal Science Advances a new method for coating soft robots with materials so that they can move and operate more efficiently. , which is tantamount to a new study that may lead to the emergence of the next generation of shape-shifting robots.

The most eye-catching aspect of this study is the major breakthrough made by the researchers in active substances, which will also become a key turning point in the design of future robots. Once such design concepts are further developed, experts can finally determine the shape, behavior and movement of soft objects through artificial control of the surface activity of the soft object (rather than the object’s innate elasticity).

Basically, the surface of most soft materials shrinks into spheres, like the condensation process of water droplets, because the surface of liquids and soft materials naturally shrink to the smallest surface area. What’s cool, though, is that, by design, actives can completely defy such natural properties. With such technologies and actives, experts expect the next generation of machines to be built from a combination of many individual active units that work together to determine how the machine moves and functions. These next-generation machines will be governed by a central controller that operates in the same way that our human tissues function.

Completely subvert the familiar laws of nature
Through the aforementioned design mechanisms, scientists will be able to create robotic arms composed of flexible materials, powered by robots on the surface of the material. Another possible breakthrough is that the size and shape of Drug Delivery Capsules can be changed by coating a layer of Responsive Materials and active materials on the surface of nanomolecules.

According to members of the research team, what is most interesting about the new study is that it completely upends the way we look at the “familiar laws of nature.” In other words, actives give us new insights into familiar laws of nature. All in all, the researchers see this study as an important and enlightening proof-of-concept, and they have developed a set of theories and simulations that can describe a 3D soft solid with a surface that is actively stressed.

The results show that active stress expands the surface of the material and exerts a pulling force on the solid below, which in turn causes the overall shape to change. The solid shape then changes as the elastic properties of the material change. The research team will now further apply this principle to design more specific robots, as well as to delve deeper into collective behavior and what happens when multiple active solids are stacked together.

Advertisement

Dinosaurs also fight each other, scientists find evidence in the largest triceratops fossil in history

We all know that Triceratops defended territory, fought and defended with three huge horns on top of their heads, and now scientists have found evidence of Triceratops fighting each other through fossil traces.

Triceratops is a plant-eating dinosaur with a total length of about 7 to 10 meters and a weight of 6 to 12 tons. It can be said to be a representative dinosaur of the late Cretaceous period. As the name suggests, Triceratops has three huge horns, which are located in the Above the eye sockets of the eyes and the bridge of the nose, many studies over the years have shown that Triceratops fought with the horns on the top of the head, and now Italian scientists have more direct evidence.

D’Annunzio University of Chieti-Pescara, Italy (D’Annunzio University of Chieti – Pescara) inspected the largest Triceratops fossil in history “Big John Big John)” and found a large hole on the right side of Big John’s neck, presumably injured by a similar species.

The Big John fossil is 66 million years old and is 8 meters high. The skull is 2.62 meters long and 2 meters wide. The two longest horns are about 1.1 meters long and over 30 cm wide, enough to withstand 16 tons of pressure. It was bought by an anonymous American collector on October 21 last year at Drouot, an auction center for art and antiques in Paris.

A team from the University of Chiedi-Pescara, Italy, found bone growth and signs of inflammation at the edge of the wound, showing that John was severely injured during his lifetime, and the wound was partially healed before his death, but why was John injured? The team speculated that it was another Triceratops, because no matter the size of the wound or the shape of the lesions, all the signs were completely consistent with the “horns” of the Triceratops, representing that Big John was fighting another Triceratops, and the opponent’s long horns stabbed the giant. John’s neck.

It’s just that the team doesn’t know whether the other Triceratops is “he” or “she”, and why they fight each other. After all, both male and female Triceratops may have horns. Unlike moose, only males can grow antlers. Male moose can grow antlers. To mate with a female, you also need to compete fiercely with other males. Scholar Ruggero D’Anastasio points out that other cases need to be studied to understand Triceratops’ behavior, but as far as he knows, other dinosaurs don’t fight each other.

Can’t get darts over coffee with friends? Study: False security infections increase risk of infection

Knowing that there is an epidemic, reducing human contact is the most effective way, but people have minimized social activities. The key to why the virus spreads so quickly may be that the risk awareness of relatives and friends is too low. A Spanish study found that people have a false sense of security in relatives and friends, thinking that those closest and safest may actually be at greatest risk.

Previous research has found that people tend to feel safe when they are in a close relationship with someone, which can lead to emotional rather than rational decisions. Confirming this intimacy paradox during the pandemic, researchers in consumer behavior and business psychology at Universidad Carlos III de Madrid, Spain, conducted five different online experiments with Americans during the pandemic. Each experiment pointed to the same result, that people may be less willing to take public health precautions to protect against COVID-19 when friends are present, or even just remembered. Even when they know that they may be infected by a friend, people’s risk awareness will suddenly decrease, and they think that the chance of reinfection from relatives and friends is less than that from strangers.

The researchers call this the friend shield effect, and the more conservative people are, the more distant they are. The study also found that people not only trust friends more, but also members of the same group, such as supporters of the same team, even strangers.

Limiting interaction with close friends and family is a common protective measure to reduce the risk of spreading the virus. “Anyone can be infected with the coronavirus, friend or foe, acquaintance or stranger, but paradoxically, the more we assume that people like us won’t infect us, the more likely we are to be infected by them,” the researchers said. infect.”

For most people, it may be thought that self-threat only comes from others, when the risk is associated with something positive like friends, the risk no longer seems to be threatening, so most people think that even when the epidemic is at its worst, going with friends is the most favorite. The number of coffee shops is also reasonable, which can explain why people have epidemic prevention awareness, but this self-awareness is not reliable, and it is difficult to rely on personal prevention for virus transmission.

“Friends and family can provide comfort, but it is unreasonable and dangerous to believe that they will protect you from COVID-19,” the researchers said. Worrying about the friend shield effect trend may exacerbate a false sense of security and lead to future contagion expansion. Some national public health guidelines encourage people to limit interactions to close circles of friends, but the researchers hope the study will provide evidence for future public health policy reminding people to be careful even with close friends. The research was published in the journal Experimental Psychology.

70% of the population is infected with three doses of vaccine firewall, Denmark returns to normal life

Compared with the closure of Shanghai, Taiwan is facing a new wave of epidemic threats. Denmark, which is far away in northern Europe, has relaxed all entry regulations and welcomes foreigners to travel. Denmark’s confidence comes from complete medical data showing that during the Omicron epidemic in the past five months, 70% of Denmark’s population has been infected with the virus. Coupled with the high vaccination rate, the virus does not pose any threat to Denmark. People don’t have to wear masks, and vaccine passports can be lost. On the other hand, return to normal life.

The Danish Institute of Infectious Diseases, based on serum antibody data from 17 to 72 years old, found that from early November to the end of March, 70% of adults were infected with Omicron, which is equivalent to 3 million positive results for a population of 5.8 million. After excluding reinfection, about 50% of the population Tested positive. A third dose of the vaccine provides adequate protection, according to medical data from Danish research institutes.

Immediately after the third dose, the vaccine provided up to 90.2% protection from hospitalization, and the risk of contracting Omicron was reduced by nearly 50%, the report noted. Four months later, it still provides up to 77.3% protection against severe disease. More than two-thirds of Denmark’s vaccines are Pfizer BioNTech, with the rest Moderna. Denmark has nearly 49,000 cases and only 16 people with severe symptoms.

Denmark opened a third dose for people over 40 in December last year and citizens over 18 at the end of January this year, but authorities said they would not allow boosters under 18, citing the belief that young people are less likely to be vaccinated or infected with the coronavirus. High immunity. The vaccine for children aged 5 to 11 was launched in November last year, and the current goal is to finish two doses.

Currently, 80.8% of the population in Denmark receives two doses of the vaccine, and 61.5% of the population is receiving the third dose. As of March this year, Denmark was among the top three countries with the highest third-dose vaccination rate among countries with a population of more than 2 million. The highest is Chile at 75%, followed by Singapore at 67%, and Italy is the same as Denmark.

The Danish government said the number of new daily cases had now dropped sharply as Denmark gained a high level of immunity, aided by a vaccination program, and declared that the new crown pneumonia no longer poses a threat to society. Denmark ended all epidemic prevention restrictions as early as February 1 and was the first EU country to lift all COVID-19 travel restrictions.

At the end of March, the Danish authorities announced that they would no longer take COVID-19 measures for travelers entering third countries. They do not need to show proof of valid vaccination, recovery or testing, and Denmark does not need to wear masks indoors except in medical institutions. Sweden and Norway have also lifted all epidemic prevention restrictions and welcomed foreigners into the country. Iceland also recently lifted all entry requirements.

But the epidemic prevention measures are not cancelled forever. The Danish Minister of Health said, “We assure the citizens of Denmark that we will only implement restrictions when it is really necessary, and we will lift them as soon as possible. This is what is happening now.” He also reminded , No one knows what will happen in the future. If a new variant virus appears, epidemic prevention measures will be restarted in a short time.

Scientists may detect intermediate-mass black hole in Andromeda Galaxy

There are many “stellar-mass” black holes in the universe, up to tens of times the mass of the sun (M☉), which are formed by the collapse of massive stars. There are also easier-to-observe “supermassive” black holes, millions to billions of times the sun’s size, located at the centers of galaxies, the cause of which has not yet been determined. Due to the huge mass difference between the two, basically stellar-mass black holes do not have enough time to evolve into supermassive black holes that existed in the early universe. There is an argument that the “seed” for the formation of supermassive black holes is between 102~5 M☉, which is the so-called “intermediate mass” black hole.

Although potentially an important key to the evolution of supermassive black holes, intermediate-mass black holes have yet to be proven. The best way to measure the mass of a black hole is to observe the motion of surrounding stars, but it is not applicable to intermediate-mass black holes, because the gravitational influence range is smaller than that of super-massive black holes, and it does not have companion star behavior for reference like stellar-mass black holes. The authenticity of intermediate-mass black holes is the direction that scientists have been striving for in recent years.

Recently, a research team used the Hubble Space Telescope and the Gemini Observatory Spectrometer to study the most massive star cluster B023-G078 in the Andromeda Galaxy (M31), and to analyze whether the dense and massive objects in the center of the cluster are intermediate-mass black holes by stellar motion. The team used Jeans anisotropic modeling to calculate the velocities of several stars within a cluster, depending on the mass and size of the central object. The best fitting model found has a mass of 9×104 M☉, which is the range of intermediate-mass black holes.

But the research team cannot rule out that the central mass is produced by a multi-stellar-mass black hole, which can be verified using a higher-resolution spectrometer. The stars in the B023-G078 cluster have a wide distribution of metallicity, and the team believes that it may be the remnant of a small galaxy that merged with Andromeda to form a stripped nuclear star cluster. Combining the observations of stellar abundance with the central mass of the stellar velocity fit, the research team tends to believe that the cluster does indeed have an intermediate-mass black hole.

Just manned back to Earth, Russia threatens to withdraw from the International Space Station again

A few days ago, Russia just used the Soyuz spacecraft to bring 3 astronauts back to Earth from the International Space Station, showing that the cooperation between the United States and Russia on the International Space Station does not seem to be affected by the Russian-Ukrainian war. Rogozin suddenly reiterated his words to withdraw from the International Space Station until Western countries lift illegal sanctions against Russia.

When Russia raised troops to invade Ukraine, the United States, Japan, Canada and several European Union countries also began to impose sanctions on the country. In the face of counterattacks from Western countries, Russia also made all-out countermeasures, such as space cooperation. Refusing to use Russian rockets to launch scheduled missions, refusing to sell rocket engines to the United States, threatening to withdraw from the International Space Station, putting the facility at risk of falling, etc.

At 3:21 am Eastern Time on March 30th, American astronaut Mark Vande Hei and 2 other Russian astronauts Anton Shkaplerov and Pyotr Dubrov returned to Earth on the Russian Soyuz MS-19 spacecraft, which originally dispelled Russia’s withdrawal from international space. Rumors of the station, I did not expect that on April 2, Dmitry Rogozin tweeted in Russian on his personal Twitter, two of which wrote “The purpose of their sanctions is to stifle the Russian economy, make the people fall into despair and starvation, and make our country submit”, ” They will not succeed, but their intentions are clear”, adding that “only if the illegal sanctions are lifted completely and unconditionally by the West, the ISS and other joint project cooperation will return to normal.”

Roscosmos will report to Russian authorities shortly when Roscosmos ends the ISS partnership, Dmitry Rogozin said, though Dmitry Rogozin’s tweet doesn’t necessarily mean the ISS is at risk of immediate disbandment, after all, he is a politically rhetorical politician But obviously as long as Western countries continue to sanction Russia, the threat to the International Space Station cannot be taken lightly.

At the same time, NASA remains committed to completing a space barter agreement with Russia for Russian astronaut Anna Kikina to participate in the Crew-5 mission launched in September this year, and NASA astronauts (according to “Spacenews”). reported that Frank Rubio may be involved in the Soyuz MS-22 mission also launched in September.

But NASA admits that the deal is still awaiting approval from the Russian government and that time is running out.

Milestone 6 reached ahead of schedule, Webb telescope completes multi-instrument calibration

Hot Topics in Space Science – The James Webb Space Telescope has been arranged quite smoothly. NASA announced on April 1 that the telescope has completed the sixth stage of the 7 major configuration process ahead of schedule. Among them, 3 of the 4 scientific instruments have been calibrated, and the rest of the mid-infrared Imaging-Spectroradiometer (MIRI) calibration work prepares the universe for observation.

The Webb Space Telescope adopts an avant-garde design. The huge main mirror is cut into 18 separate mirrors in order to be stuffed into the rocket payload bay. For this reason, the Webb Space Telescope launches into space and unfolds a series of 7 large mirrors that last longer than previous space telescopes. Configuration process, these steps are:

• Segment Image Identification
• Segment Alignment
• Image Stacking
• Coarse Phasing
• Fine Phasing
• Multi-instrument field of view alignment
• Iterative calibration for final correction

After completing the precise phase adjustment, the telescope NIRCam instrument was aimed at the star 2MASS J17554042+6551277 (also known as TYC 4212-1079-1), which is about 2,000 light-years away from us and 16 times brighter than the sun. The most intense infrared image of a star.

After that, the telescope further completed the calibration of the remaining three scientific instruments, and on April 1, NASA announced that the sixth stage of the configuration process had been completed ahead of schedule. The near-infrared camera (NIRCam) is already aligned with the mirrors of the telescope, and since the previous calibration was so precise, no additional secondary mirror adjustments were required before the seventh and final stages.

All scientific instruments are left with the Mid-Infrared Imaging-Spectrometer (MIRI) waiting to complete the calibration. The NASA team is waiting for it to cool down to a working temperature of minus 266°C, which is expected to take several weeks. The telescope will then enter the seventh stage of the configuration process, the final milestone before the Webb telescope is fully operational.

Astronomers are waiting for the Webb telescope to unlock the secrets of dark matter, analyze exoplanet atmospheres for signs of life, and try to find the universe’s first stars.

6 hours to generate deadly poison: AI that must not be abused

Many people feel that it is not easy to make drugs, and at least knowledge of chemistry is required. But what if you ask artificial intelligence to help? And what the AI ​​system “makes” is not drugs but poison.

The paper in Nature Machine Intelligence with Fabio Urbina as the first author mentions that his company, Collaborations Pharmaceuticals, recently released a machine learning model for predicting toxicity. Invited to the Swiss NBC (Nuclear, Biological and Chemical) Conservation Institute meeting to discuss the development of tools that cutting-edge chemistry and biotechnology could have an impact on, Collaborations Pharmaceuticals was invited to talk about the potential misuse of AI technologies.

Urbina said the issue didn’t seem to have been thought of before because decades of machine learning models have discovered new druggable molecules, and the use of computers and artificial intelligence is about improving human health, not destroying it. Collaborations Pharmaceuticals decided to explore how to use AI to design toxic molecules, previously designing a commercial de novo molecule generation model called MegaSyn, using machine learning models to predict biological activity and find new therapeutic inhibitors for human disease targets.

Such generative models typically penalize predicted toxicity and reward predicted target activity, then adjust the guidance model to reward both toxicity and biological activity, and train AI using public repositories of molecules. The adjusted underlying generative software is built on readily available open-source software, and in order to narrow down the molecular scope, the generative model is pushed towards compounds such as the nerve agent VX.

VX is a man-made chemical warfare agent of nerve agent (chemical warfare agent: the purpose of war, with severe toxicity, large-scale poisoning or killing enemy humans, animals and plants and other chemical substances), strong toxicity and rapid action, 6~10 mg of VX particles is enough fatal. The new model generated 40,000 molecules within 6 hours of starting the server. Artificial intelligence not only designed VX, but also designed many known chemical warfare agents, and also designed many new molecules that seem to be equally reasonable. According to the predicted value, the new molecules are more toxic than known chemical warfare agents.

The repositories for training AI do not include these nerve agents, but reversing the machine learning model turns a harmless generative model from a useful medical tool into a lethal molecular generator. Models created to avoid toxicity become “double-edged”. The better a researcher can predict toxicity, the more effective a generative model will be at guiding the design of new molecules in a chemical space that is largely composed of lethal molecules.

Collaborations Pharmaceuticals did not evaluate the synthesizability of the model-generated virtual molecules, nor did they explore how to manufacture them, but the process has an off-the-shelf business model and open-source software. While they also didn’t physically synthesize any molecules, there are hundreds of commercial companies around the world that do.

This proves one thing: non-humans can make lethal chemical weapons.

While knowledge of chemistry or toxicology is currently required to generate toxic substances or biological agents that can cause significant harm, the addition of machine learning models greatly reduces the technical threshold and may only require the ability to code and understand the output of the model. Commercial tools, open-source software tools, and public repositories are all available for unsupervised use, and the use of artificial intelligence to generate models of harmful molecules appears to be a “Pandora’s box.” These molecules can be easily removed, but not how they were created.

Clearly, ways must be found to avoid AI misuse. Urbina believes that AI chemical warfare isn’t going anywhere anytime soon, but it is a possibility. MegaSyn is a commercial product that can control who can access it, and restrictions may be added in the future. Like the OpenAI “GPT-3” language model, although it can be used at any time, it can also cut off users’ access rights.

Urbina also mentioned that universities should also redouble their efforts to train science students in ethics, which can be extended to other disciplines, especially computer science students, to make them aware of the potential for artificial intelligence abuse. This attempt seems to once again confirm a sentence: technology is innocent, whether it benefits or does evil, depending on the purpose of the user.

Astronomers discover protoplanetary disk in Orion molecular cloud

Using the Very Large Array (VLA) and the Atacama Large Millimeter and Submillimeter Array (ALMA), astronomers detected 97 disks of gas and dust around young protostars in the constellation Orion. Orion is not only the brightest constellation in the winter sky, but also the star-forming region closer to Earth.

The researchers said that the gas and dust clouds collapse to form stars under their own gravitational instability. The collapsed material is affected by the initial angular momentum. Most of the material in the cloud will form a disk, and the material will be accreted to the star through the disk, and the planets are also in the disk. If we can understand the characteristics of the entire evolution process, it will be an important key to unravel the formation of planets.

About 1,400 light-years from Earth, this molecular cloud in the constellation Orion is a massive star-forming region. Dust around young stars blocks most of the star’s visible light, and radio waves can travel through the dust clouds to learn more about young star systems. Astronomers analyzing VLA and ALMA data, known as VANDAM, is the largest ever survey of young stars.

The survey measured the size and mass of many young protoplanetary disks and compared them with older protoplanetary disks studied by ALMA, and found that new protoplanetary disks are larger than older protoplanetary disks at the same size. This result is actually quite reasonable, because the star will capture nearby material and make the surrounding disk smaller, but it means that the young disk has more material to form planets, and the largest planets in the planetary system may have formed around very young stars.

Older protoplanetary disks usually have rings and significantly less material inside them. These gaps are usually regions where planets are forming, but may also be disk resonance structures, where the gaps are formed by the gravitational pull of young planets, similar to Jupiter in the asteroid belt. Create track clearance. The research team found a similar gap structure in a protoplanetary disk that was only 100,000 years old. The time was unexpectedly early. The researchers said that in the first 1 million years of the system, the disk structure was similar to the older disk. The survey saw that some systems have very different shapes. Irregular, it is suspected that the system may be young, so that the disk has not yet formed, or maybe even the protostar has not fully formed. The research was published in The Astrophysical Journal.

The downpour in space reveals a new mechanism that promotes “electronic rain”

Charged particles will normally accumulate in the magnetosphere around the earth and participate in the process of producing the earth’s auroras. A new study by the UCLA team points out that a type of electromagnetic wave in the radiation belt around the earth can trigger a larger “electron rain”, which may become an invisible way to damage satellites or human safety in future space travel if not careful.

The magnetosphere around Earth is full of electrons or other charged particles, known as the Van Allen radiation belt, in which electrons travel in a Slinky-like spring, bouncing back and forth between the north and south poles, when the solar wind or the sun Storms can blow these particles into Earth’s atmosphere and cause auroras.

Under certain conditions, whistler waves are generated in the radiation belt to excite plasma electrons and accelerate them. Recently, a UCLA team combined data from the ELFIN satellite and NASA THEMIS probe to find that another form is larger. The new mechanism for the range “electron rain” comes from whistling waves, which accelerate electrons and fall out of the Van Allen radiation belt. Compared to normal electron rain, the electron rain accelerated by whistling waves moves. Faster and with greater reach.

The researcher Vassilis Angelopolous explained that the Van Allen radiation belts can be imagined as “space reservoirs” filled with electrons. When the reservoir is full, the electrons will descend in a spiral manner to prevent overflow; but when the reservoir rushes a big wave, the shaking electrons will overflow. “Electron rain” forms at the edges.

The team further showed that during the Earth’s magnetic storm, this type of radiation will significantly intensify the impact on the earth, causing hidden harm to satellites, probes, and astronauts. However, the current space weather prediction model has not yet included the electron rain caused by whistling waves. Missing out reduces prediction accuracy.

The new paper was published in the journal Nature Communications.