The first convertor transformer using China-made on-load tap changers have successfully been put into operation on Sunday at a crucial west-to-east power transmission project located in South China's Guangdong Province, according to a report published by xinhuanet.com. 

Feng Dong, a senior executive at a subsidiary of the China Southern Power Grid, was quoted by the report as saying that China had completed the technological breakthrough from scratch in field of convertor transformer on-load tap changers, and has achieved full localization of components and other products' industrial chains.

This marks the fact that China has officially broken through the restrictions of this core technology in high-end electric equipment, Feng said.

Previously, long-distance, large capacity and high voltage direct current facilities are required for the transmission of electricity from western to eastern areas in China, and both terminals for transmitting and receiving power need to use the equipment of converter transformer that weighs more than 300 tons.

On-load tap changers of a convertor transformer are used to adjust the voltage, power load and current, similar to the function of a gearbox in a car. 

Deng Jun, a senior technical expert at the aforementioned company, also said that an on-load tap changer of a convertor transformer has about 1,000 components, and is a highly complex and sophisticated piece of equipment.

According to the Xinhua report, this technology used to be grasped by only a few overseas companies, and when technical fault took place previously, Chinese companies had no choice but to replace the products with imported goods of the same model, whose ordering cycle took about three to four months, thus posing challenges to the safety of power operation in the country. 

The report also cited a deputy general manager of the company as saying that the company has established a team in partnership with upper stream and downstream companies along the industrial chains. 

After more than two years' of efforts, the team has broken through vacuum switch tubes and other technical bottlenecks to successfully research the large capacity convertor transformer on-load tap changer with rated capacity of 6,000 kilovolt-ampere, maximum voltage of 6,000 volt and maximum rated current of 1,300 ampere.

Using the domestically made on-load tap changers could save nearly 40 million yuan ($5.56 million) In the building of ultra-high voltage direct current power transmission projects, the manager said. 

China successfully sent the Land Exploration-4 01 satellite, the world's first high-orbit synthetic aperture radar (SAR) satellite, into a preset orbit via a Long March-3B carrier rocket from the Xichang Satellite Launch Center in Southwest China's Sichuan Province at 1:26 am on Sunday.

The Global Times learned from the China National Space Administration (CNSA) which oversaw the organization of the launch and manages the satellite program, that the newly launched satellite is the world's first high-orbit SAR satellite that has entered the engineering implementation phase. Able to provide all-weather and all-day observation of China's territory and surrounding areas, it will further improve the country's space-based disaster monitoring system and is of great significance for comprehensively boosting the country's disaster prevention, reduction, and relief capabilities.

The Land Exploration-4 01 satellite is a remote sensing research satellite listed in the country's Medium and Long Term Development Plan for Civilian Space Infrastructure (2015-2025.)

The satellite operates in an inclined geosynchronous orbit and is equipped with a synthetic aperture radar payload with high resolution, wide coverage, multiple modes, and lightweight advantages, the CNSA revealed.

Compared with low-orbit satellites and optical satellites, the Land Exploration-4 01 satellite combines the advantages of a short revisit period and large imaging swath in high-orbit observation with the advantages of microwave observation that is not limited by weather conditions (all-weather) and not limited by lighting conditions (all-day), which can improve the accuracy and efficiency of identifying abnormal changes in weather and enhance the nation's comprehensive disaster prevention and control capabilities, the CNSA said in a press release sent to the Global Times on Sunday.

With the satellite now in orbit, it will enrich China's key regional observation methods and provide all-weather and all-day observation of China's territory and surrounding areas, meeting the needs of disaster prevention and reduction, earthquake monitoring, land and resources surveying, as well as applications in industries such as the marine, water conservancy, meteorology, agriculture, environmental protection, and forestry industries, according to the press release.

State departments led by China's Ministry of Emergency Management, including the Ministry of Natural Resources, Ministry of Water Resources and China Meteorological Administration, are key users of the satellite and they will carry out construction of ground systems and operation systems according to their specific needs.

The satellite was developed by the China Academy of Spacecraft Technology (CAST.)

This was the second disaster prevention-related satellite launched within a week by China, following the codenamed Environmental Surveyor 2F, launched by a Long March 2C rocket from the Taiyuan Satellite Launch Center in North China's Shanxi Province on Wednesday.

Also developed by CAST in Beijing, the satellite is tasked with using its synthetic aperture radar to obtain images and data to support disaster prevention and mitigation, ecological monitoring and emergency response efforts. Its users are the Ministry of Emergency Management and the Ministry of Ecology and Environment.

On Sunday, space industry observers hailed the country's innovative strength in the space domain, which they say has been increasingly creating value in civilian applications and shows that the country's space development upholds the concept of "putting people first."

During the recent heavy rainfall that impacted the Beijing-Tianjin-Hebei region in North China as well as Northeast China's Heilongjiang and Jilin provinces, 16 satellites, including Gaofen-3 remote sensing satellites, were deployed to provide rapid imaging services to assist disaster monitoring, according to the state-owned aerospace giant China Aerospace Science and Technology Corporation (CASC) on Saturday.

The CASC told the Global Times on Sunday that these near real-time satellite images taken over the hardest-hit flood areas have provided scientific data services to support disaster relief work.

Three men from Southwest China’s Guizhou Province who attempted to illegally cross the border into Myanmar to engage in telecom fraud have been handed prison sentences ranging from four to six months, a local intermediate people’s court announced on Monday. 

Before the three men surnamed Wu, Huang and Yang were apprehended by police in Southwest China’s Yunnan Province when they attempted to illegally cross the border into Myanmar this February, it was discovered that the group had already crossed the border and entered Myanmar on multiple occasions.  

Wu had successfully illegally crossed the border between China and Myanmar in July of 2019, October of 2019, March of 2020 and October of 2020. He was rejected by the local crime syndicates there because he could not type and was unable to be part of the syndicate’s local telecom fraud operations. 

Huang also illegally crossed the border between China and Myanmar in January of 2019, July of 2019 before being apprehended when he attempted to cross the border in August of 2020. 

Yang illegally crossed the border in March of 2019. He illegally crossed the border again in May of 2020 but turned himself in December of 2020 upon returning to China. 

The three defendants had planned to travel to Myanmar together in February but were discovered on route in Yunnan. 

Their behaviors violated the laws and regulations governing border management and committed the crime of illegal border crossing. 

According to China’s Criminal Law, Wu was sentenced to six months in prison and was fined 7,000 yuan ($965). Huang was handed five months in detention and was fined 6,800 yuan while Yang was sentenced to four months detention and fined 6,800 yuan. 

The local judge noted in the decision that the public must remain vigilant to the pitfalls of high-paying jobs abroad and that overseas jobs should be sought through normal employment channels.

A wandering baby Jupiter could help explain why there are no planets closer to the sun than Mercury and why the innermost planet is so tiny, a new study suggests.

Jupiter’s core might have formed close to the sun and then meandered through the rocky planet construction zone. As the infant Jupiter moved, it would have absorbed some planet-building material while kicking out the rest. This would have starved the inner planets — Mercury, Venus, Earth and Mars — of raw materials, keeping them small and preventing any other planets from forming close to the sun, say planetary scientist Sean Raymond and colleagues online March 5 in Monthly Notices of the Royal Astronomical Society.
“When I first came up with it, I thought it was ridiculous,” says Raymond, of the Laboratory of Astrophysics of Bordeaux in Floirac, France. “This model is kind of crazy, but it holds up.”

Rocky planets snuggled up to their suns are common in our galaxy. Many systems discovered by NASA’s Kepler space telescope have multiple planets — several larger than Earth — crammed into orbits smaller than Mercury’s. Though Kepler is biased toward finding scrunched-up solar systems, researchers wonder why there is a large gap between the sun and Mercury.

Scientists suspect that the inner planets of our solar system formed 4.6 billion years ago from a belt of debris that stretched between the current orbits of Venus and Earth. Mercury and Mars were built out of material along the edges of this belt, which explains why they are relatively small. Jupiter, traditionally thought to have formed much farther out, gets the blame for creating the belt’s outer edge. What shaped the inner edge has remained difficult to explain (SN Online: 3/23/15).

Raymond and colleagues ran computer simulations to see what would happen to the inner solar system if a body with three times the mass of Earth started inside Mercury’s orbit and then migrated away from the sun. They found that if the interloper didn’t move too fast or too slow, it would sweep clean the innermost parts of the disk of gas and dust that encircled the young sun and leave just enough material to form the rocky planets.

Raymond and colleagues also discovered that young Jupiter could have corralled enough debris to form a second core — one that got nudged away from the sun as Jupiter migrated. This second core could be the seed from which Saturn grew, the researchers suggest. Jupiter’s gravity could have dragged debris to the asteroid belt, too. Raymond says that might explain the origin of iron meteorites, which some researchers argue should have formed relatively close to the sun.
Jupiter plowing through the inner solar system sounds plausible, says Sourav Chatterjee, an astrophysicist at Northwestern University in Evanston, Ill. “But there are several ways this can go wrong.”

Building a giant planet core inside the orbit of Mercury is not hard, he says. Pebbles and boulders in the nascent solar system probably drifted inward. They could have piled up close to the sun where solar magnetic fields created turbulence that trapped infalling material. If just a fraction of this debris stuck together, a rocky orb a few times as massive as Earth could form.

Having proto-Jupiter wander to the outer solar system, however, is asking a lot, says Chatterjee. Gravitational interactions with spiral waves in the disk that surrounded the sun can propel a newborn planet either inward or outward. But how fast, how far and in which direction the planet travels depends on properties such as disk temperature and density, which Raymond and colleagues readily acknowledge. Their simulations assume and simplify disk characteristics to see if building the solar system inside-out is even plausible.

“We’re building up a logical chain that shows [this idea] is not completely crazy,” Raymond says. “We’re not saying it happened. Just if it happened, what would it do?”

The last of a group of dense minerals that make up much of Earth’s crust and upper mantle has been found tucked inside a meteorite that slammed into Australia 135 years ago. The newly discovered mineral, a variety of majorite, is potentially abundant in sinking tectonic plates and could help illuminate the behavior of the deep Earth, its discoverers say.

Each identical component of this mineral contains 32 magnesium atoms, 32 silicon atoms and 96 oxygen atoms arranged in a distorted cube. Natural samples of MgSiO3 tetragonal garnet, the mineral’s scientific moniker, had eluded scientists since the mineral was first artificially produced in 1985.
Naotaka Tomioka, a mineralogist at the Kochi Institute for Core Sample Research in Japan, and colleagues discovered 0.5-micrometer-wide grains of the mineral in a slice of the 19th century meteorite. While many minerals found in meteorites form when slamming into Earth, the new mineral formed in space when two asteroids collided at a relative speed of about 2 kilometers per second, the researchers report online March 25 in Science Advances.

One challenge remains for the researchers: As discoverers of the mineral, they now get to name it.

Thousands of national parks have been established around the world to preserve wildlife. But towns, farms, ranches and roads have grown up around many of these parks, creating islands of wilderness in a sea of humanity. If the creatures inside are to thrive, they need ways to travel between the islands, contends “Wild Ways,” a new documentary from the TV series NOVA.

Isolation can be especially troublesome for large predators, such as lions, that live alone or in small groups. In some areas of Africa, lions can move between populations to avoid inbreeding. But some lions, such as the few in Tanzania’s Ngorongoro Crater, are cut off from other groups. In such populations, cubs are born smaller, die younger and are more susceptible to disease. And drought or overhunting could easily wipe them out, the show notes.
To connect these smaller populations, conservationists are now building wildlife corridors between parks. One of the most ambitious projects is the Yellowstone to Yukon Conservation Initiative, which aims to create connections between grizzly bears in the Canadian Arctic and the western United States. Other large wildlife corridors are being planned in Central America, eastern Australia and the Himalayas. But there are often roadblocks. It can be difficult to persuade people to spend money on wildlife, and it can be even harder when those animals kill livestock or humans.

“It is important that we provide incentives for local communities, in particular, who should now look at wildlife as some form of economic asset to themselves,” says Simon Munthali of the Kavango-Zambezi Transfrontier Conservation Area, which is attempting to connect parks in five countries across southern Africa. With the right incentives, people will be more accepting of wildlife moving across land and may even benefit from it, he says in the documentary. Botswana, for instance, has developed a large ecotourism industry that provides jobs and money for local people, motivating animal protection.

The documentary is a bit too optimistic about the removal of hurdles that stand in the path of wildlife corridors, especially in the American West, where there is ongoing debate about how to manage public lands. And then there is the question of whether these corridors can be created fast enough to save the world’s dwindling animal populations. But, as Michael Soulé, one of the founders of the field of conservation biology, says: “It’s our last chance to protect the diversity of life on Earth.” “Wild Ways” makes a convincing case that we should be willing to try.

Parasitic worms may hold the secret to soothing inflamed bowels.

In studies of mice and people, parasitic worms shifted the balance of bacteria in the intestines and calmed inflammation, researchers report online April 14 in Science. Learning how worms manipulate microbes and the immune system may help scientists devise ways to do the same without infecting people with parasites.

Previous research has indicated that worm infections can influence people’s fertility (SN Online: 11/19/15), as well as their susceptibility to other parasite infections (SN: 10/5/13, p. 17) and to allergies (SN: 1/29/11, p. 26). Inflammatory bowel diseases also are less common in parts of the world where many people are infected with parasitic worms.
P’ng Loke, a parasite immunologist at New York University School of Medicine, and colleagues explored how worms might protect against Crohn’s disease. The team studied mice with mutations in the Nod2 gene. Mutations in the human version of the gene are associated with Crohn’s in some people.

The mutant mice develop damage in their small intestines similar to that seen in some Crohn’s patients. Cells in the mice’s intestines don’t make much mucus, and more Bacteroides vulgatus bacteria grow in their intestines than in the guts of normal mice. Loke and colleagues previously discovered that having too much of that type of bacteria leads to inflammation that can damage the intestines.
In the new study, the researchers infected the mice with either a whipworm (Trichuris muris) or a corkscrew-shaped worm (Heligmosomoides polygyrus). Worm-infected mice made more mucus than uninfected mutant mice did. The parasitized mice also had less B. vulgatus and more bacteria from the Clostridiales family. Clostridiales bacteria may help protect against inflammation.
“Although we already knew that worms could alter the intestinal flora, they show that these types of changes can be very beneficial,” says Joel Weinstock, an immune parasitologist at Tufts University Medical Center in Boston.

Both the increased mucus and the shift in bacteria populations are due to what’s called the type 2 immune response, the researchers found. Worm infections trigger immune cells called T helper cells to release chemicals called interleukin-4 and interleukin-13. Those chemicals stimulate mucus production. The mucus then feeds the Clostridiales bacteria, allowing them to outcompete the Bacteroidales bacteria. It’s still unclear how the mucus encourages growth of one type of bacteria over another, Loke says.

Blocking interleukin-13 prevented the mucus production boost and the shift in bacteria mix, indicating that the worms work through the immune system. But giving interleukin-4 and interleukin-13 to uninfected mice could alter the mucus and bacterial balance without worms’ help, the researchers discovered.

Loke and colleagues also wanted to know if worms affect people’s gut microbes. So the researchers took fecal samples from people in Malaysia who were infected with parasitic worms.

After taking a deworming drug, the people had less Clostridiales and more Bacteriodales bacteria than before. That shift in bacteria was associated with a drop in the number of Trichuris trichiura whipworm eggs in the people’s feces, indicating that getting rid of worms may have negative consequences for some people.

Having data from humans is important because sometimes results in mice don’t hold up in people, says Aaron Blackwell, a human biologist at the University of California, Santa Barbara. “It’s nice to show that it’s consistent in humans.”

Worms probably do other things to limit inflammation as well, Weinstock says. If scientists can figure out what those things are, “studying these worms and how they do it may very well lead to the development of new drugs.”

Before anybody even had a computer, Claude Shannon figured out how to make computers worth having.

As an electrical engineering graduate student at MIT, Shannon played around with a “differential analyzer,” a crude forerunner to computers. But for his master’s thesis, he was more concerned with relays and switches in electrical circuits, the sorts of things found in telephone exchange networks. In 1937 he produced, in the words of mathematician Solomon Golomb, “one of the greatest master’s theses ever,” establishing the connection between symbolic logic and the math for describing such circuitry. Shannon’s math worked not just for telephone exchanges or other electrical devices, but for any circuits, including the electronic circuitry that in subsequent decades would make digital computers so powerful.

It’s now conveniently a good time to celebrate Shannon’s achievements, on the occasion of the centennial of his birth (April 30) in Petoskey, Michigan, in 1916. Based on the pervasive importance of computing in society today, it wouldn’t be crazy to call the time since then “Shannon’s Century.”

“It is no exaggeration,” wrote Golomb, “to refer to Claude Shannon as the ‘father of the information age,’ and his intellectual achievement as one of the greatest of the twentieth century.”

Shannon is most well-known for creating an entirely new scientific field — information theory — in a pair of papers published in 1948. His foundation for that work, though, was built a decade earlier, in his thesis. There he devised equations that represented the behavior of electrical circuitry. How a circuit behaves depends on the interactions of relays and switches that can connect (or not) one terminal to another. Shannon sought a “calculus” for mathematically representing a circuit’s connections, allowing scientists to be able to design circuits effectively for various tasks. (He provided examples of the circuit math for an electronic combination lock and some other devices.)

“Any circuit is represented by a set of equations, the terms of the equations corresponding to the various relays and switches in the circuit,” Shannon wrote. His calculus for manipulating those equations, he showed, “is exactly analogous to the calculus of propositions used in the symbolic study of logic.”

As an undergraduate math (and electrical engineering) major at the University of Michigan, Shannon had learned of 19th century mathematician George Boole’s work on representing logical statements by algebraic symbols. Boole devised a way to calculate logical conclusions about propositions using binary numbers; 1 represented a true proposition and 0 a false proposition. Shannon perceived an analogy between Boole’s logical propositions and the flow of current in electrical circuits. If the circuit plays the role of the proposition, then a false proposition (0) corresponds to a closed circuit; a true proposition (1) corresponds to an open circuit. More elaborate math showed how different circuit designs would correspond to addition or multiplication and other features, the basis of the “logic gates” designed into modern computer chips.

For his Ph.D. dissertation, Shannon analyzed the mathematics of genetics in populations, but that work wasn’t published. In 1941 he began working at Bell Labs; during World War II, he wrote an important (at the time secret) paper on cryptography, which required deeper consideration of how to quantify information. After the war he developed those ideas more fully, focusing on using his 1s and 0s, or bits, to show how much information could be sent through a communications channel and how to communicate it most efficiently and accurately.

In 1948, his two papers on those issues appeared in the Bell System Technical Journal. They soon were published, with an introductory chapter by Warren Weaver, in a book titled The Mathematical Theory of Communication. Today that book is regarded as the founding document of information theory.

For Shannon, communication was not about the message, or its meaning, but about how much information could be communicated in a message (through a given channel). At its most basic, communication is simply the reproduction of a message at some point remote from its point of origin. Such a message might have a “meaning,” but such meaning “is irrelevant to the engineering problem” of transferring the message from one point to another, Shannon asserted. “The significant aspect is that that actual message is one selected from a set of possible messages.” Information, Shannon decided, is a measure of how much a communication reduces the ignorance about which of those possible messages has been transmitted.

In a very simple communication system, if the only possible messages are “yes” and “no,” then each message (1 for yes, 0 for no) reduces your ignorance by half. By Shannon’s math, that corresponds to one bit of information. (He didn’t coin the term “bit” — short for binary digit — but his work established its meaning.) Now consider a more complicated situation — an unabridged English dictionary, which should contain roughly half a million words. One bit would correspond to a yes-or-no that the word is in the first half of the dictionary. That reduces ignorance, but not very much. Each additional bit would reduce the number of possible words by half. Specifying a single word from the dictionary (eliminating all the ignorance) would take about 19 bits. (This fact is useful for playing the game of 20 Questions — just keep asking about the secret word’s location in the dictionary.)

Shannon investigated much more complicated situations and devised theorems for calculating information quantity and how to communicate it efficiently in the presence of noise. His math remains central to almost all of modern digital technology. As electrical engineer Andrew Viterbi wrote in a Shannon eulogy, Shannon’s 1948 papers “established all the key parameters and limits for optimal compression and transmission of digital information.”

Beyond its practical uses, Shannon’s work later proved to have profound scientific significance. His math quantifying information in bits borrowed the equations expressing the second law of thermodynamics, in which the concept of entropy describes the probability of a system’s state. Probability applied to the ways in which a system’s parts could be arranged, it seemed, mirrored the probabilities involved in reducing ignorance about a possible message. Shannon, well aware of this connection, called his measure entropy as well. Eventually questions arose about whether Shannon’s entropy and thermodynamic entropy shared more than a name.

Shannon apparently wasn’t sure. He told one writer in 1979 that he thought the connection between his entropy and thermodynamics would “hold up in the long run” but hadn’t been sufficiently explored. But nowadays a deep conceptual link shows up not only between Shannon’s information theory and thermodynamics, but in fields as diverse as quantum mechanics, molecular biology and the physics of black holes.
Shannon’s understanding of information plays a central role, for instance, in explaining how the notorious Maxwell’s demon can’t violate thermodynamics’ second law. Much of that work is based on Landauer’s principle, the requirement that energy is expended when information is erased. In developing that principle, Rolf Landauer (an IBM physicist) was himself influenced both by Shannon’s work and the work of Sadi Carnot in discerning the second law in the early 19th century.

Something Shannon and Carnot had in common, Landauer once emphasized to me, was that both discovered mathematical restrictions on physical systems that were independent of the details of the system. In other words, Carnot’s limit on the efficiency of steam engines applied to any sort of engine, no matter what it was made of or how it was designed. Shannon’s principles specifying the limits on information compression and transmission apply no matter what technology is used to do the compressing or sending. (Although in Shannon’s case, Landauer added, certain conditions must be met.)

“They both find limits for what you can do which are independent of future inventions,” Landauer told me. That is, they have grasped something profound about reality that is not limited to a specific place or time or thing.

So it seems that Shannon saw deeply not only into the mathematics of circuits, but also into the workings of nature. Information theorist Thomas Cover once wrote that Shannon belongs “in the top handful of creative minds of the century.” Some of Shannon’s original theorems, Cover noted, were not actually proved rigorously. But over time, details in the sketchy proofs have been filled in and Shannon’s intuitive insights stand confirmed. “Shannon’s intuition,” Cover concluded, “must have been anchored in a deep and natural theoretical understanding.” And it seems likely that Shannon’s intuition will provide even more insights into nature in the century ahead.

A decent office scanner has beaten X-ray blasts from multimillion-dollar synchrotron setups in revealing how air bubbles kill plant leaves during drought.

Intricate fans and meshes of plant veins carrying water are “among the most important networks in biology,” says Timothy Brodribb of the University of Tasmania in Hobart, Australia. When drought weakens the water tension in veins, air from plant tissues bubbles in, killing leaves much as bubble embolisms and clots in blood vessels can kill human tissue. As climate change and population growth increase risks of water shortage, Brodribb and other researchers are delving into the details of what makes some plants more resistant than others to drought.
The high energy of X-rays destroys delicate leaf tissue. So, based on a chat with microfluidics specialist Philippe Marmottant of the French National Center for Scientific Research, Brodribb tried repeatedly scanning a leaf with a light source below it to reveal darkening lines as air bubbles shot through the veins. A microscope or scanner proved perfect. Tracked this way, an invasion of killer bubbles “looks like a lightning storm,” he says.

He was surprised to see that bigger veins, despite their robust looks, fail before tiny ones (blue indicates earliest failures; red, the latest), as seen in an oak leaf (lower right) and Pteris fern (top). And networks in ferns with simpler branching patterns, as in the Adiantum ferns at bottom left, crash quickly.

This system of visualizing plant plumbing gave better resolution than expensive and elaborate X-ray techniques had, Brodribb, Marmottant and Diane Bienaimé report online April 11 in the Proceedings of the National Academy of Sciences.

Something catapulted a pair of stars from the outer rim of our galaxy, but astronomers aren’t sure what. A binary star known as PB 3877 is rocketing away at about 2 million kilometers per hour — possibly fast enough to escape the galaxy’s gravitational pull — and all the usual explanations for such speedy stars fall short. Astrophysicist Péter Németh of the University of Erlangen-Nuremberg in Germany and colleagues report the discovery in the April 10 Astrophysical Journal Letters.

Many galactic escapees get kicked out after a close brush with the supermassive black hole in the Milky Way’s center. But PB 3877, first noticed in 2011 and currently about 18,000 light-years away in the constellation Coma Berenices, has been nowhere near that behemoth. A supernova could be responsible; it has happened before (SN Online: 3/5/15). But PB 3877 is two stars traveling together. A supernova would have torn the two apart. Németh and colleagues propose that the duo may be left over from a smashup between the Milky Way and a smaller galaxy. If that’s the case, then there might be others like PB 3877 lurking in the galactic outskirts.