China Science & Technology Forum

[Cybernetics]

China's carbon fiber development documentary. Production of T300 to T1000 carbon fiber.

 

[JSCh]

Scientists unlock genetic secrets of the rose
By Angus McNeice | chinadaily.com.cn | Updated: 2018-05-03 01:29

Rosa chinensis in bloom. [Photo provided to chinadaily.com.cn]​

Breakthrough could lead to brighter, more scented blooms

Gardeners could soon be growing genetically engineered roses of new sizes, colors and scents after scientists from Europe and China sequenced the flower’s genome for the first time.

A team of geneticists from the United Kingdom, France, Germany, Huazhong Agricultural University in Wuhan and the Chinese Academy of Agricultural Sciences in Beijing have successfully mapped the 36,377 genes that make up the Chinese rose species Rosa chinensis, commonly known as Old Blush.

Their research has been published in the journal Nature, and the breakthrough means that researchers will now be able to pinpoint genes that control specific traits, opening the door for future strains of genetically engineered roses that are pest-resistant, last longer in the vase, and have a wider diversity of scents and colors.

“The rose is one of the most important flowers in the world,” said Mohammed Bendahmane, a geneticist from ENS Lyon university and lead author on the study. “It has a huge capacity of usage - as a garden flower, as cut flowers, for production of oils for cosmetics and medicinal purposes - it’s a really important species.”

Roses are the best sellers in the international cut flower industry, which is worth around $20 billion annually. Plant geneticist Antoine Larrieu, from Leeds University, one of the report’s co-authors, said now the genome has been mapped, editing tools such as CRISPR/Cas9 could be used to create new strains of roses.

“CRISPR has been used in different plants species like tomato, wheat, rice, and it works really well, we know that it can make very precise modifications in the genome,” Larrieu said. “It has not been used on roses yet, but now we have the reference sequence, it’s just a question of doing it and going through a period of trial and error.”

In roses, Larrieu explained, there is an inverse relationship between scent and color – meaning hybrids with a vivid color usually do not have a potent scent, and vice versa. He said gene editing could potentially resolve this, leading to “very flashy roses that have a very strong scent”.

Rosa chinensis was selected for study, said Bendahmane, because it is one of the original parent roses of most modern varieties. Around 10 species of roses were introduced to Europe in the 18th century, from which around 40,000 species have since been bred.

“Rosa chinensis … was brought to Europe from China by French and British missionaries,” he said. “By sequencing the parents, we can understand the composition of modern roses.”

Jennifer Potter, horticultural historian and author of The Rose: A True History, said that Chinese people were among the first to domesticate roses.

“Chinese roses came into Europe and they brought wonderful new qualities - they had brighter colors, wonderful shiny leaves, a delicate scent, and petals like silk rather than heavy damask,” Potter said.

“And they were recurrent bloomers - that is what was so precious about the Chinese roses. People fell in love with them, they had a massive impact on rose breeding.”

 

[JSCh]

China dives into original eye research using big data
Henry Zheng
2018-05-03 16:15 GMT+8

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China is leading the way in finding the cause of nearsightedness, or myopia, using smart wear and big data to help.

Chinese researchers will head a high-profile international collaboration relying on AI and data analytics to find the mechanism behind environmental factors that cause myopia, according to Xinhua.

Myopia is a growing global concern, especially in East Asia where it affects about 80 percent of 18-year-old students, says a 2012 study in The Lancet. The condition can even lead to more serious diseases such as glaucoma and retinal detachment, eye expert Xu Xun told SCMP.

Conventional wisdom was that reading or staring at screens for too long were the primary culprits, but a growing body of evidence in recent years suggests that exposure to strong or low lighting is linked to eye growth – myopia is the result of a longer eyeball – in children. This has led some to conclude that more time spent outside in natural light would decrease the risk of getting myopia. Therefore, the mechanism pathway of how light intensity contributes to this lengthening will be a target of study.

Although many corrective options such as eyeglasses and contacts have developed over the years, little is known about how environmental factors such as ambient light influence the eye. Previous studies linking less myopia with more time spent outdoors relied on questionnaires, in which people did not accurately recall their experiences, notes research in Investigative Ophthalmology & Visual Science.

Therefore, the collaborative project aims to use smart wear instead of self-reporting to measure a person’s surroundings. The Xinhua article states that a sensor called the “Clouclip,” yunjia in Chinese, will be used to record data.

According to the news agency's website, the “Clouclip” can be attached to the frames of eyeglasses while a person reads or stares at a screen. The product page says that it can detect the brightness of your surroundings, the angle of your head tilt, and time spent outdoors. It even vibrates if you spend too long looking at something. All this data, of course, can be tracked in an accompanying app for analysis, a convenience that's central to the project.

With projections that half the global population will have myopia by 2050, the stakes are higher than ever for researchers to crack the problem.

 

[JSCh]

China develops world’s first digital positron emission tomography
CGTN
2017-12-13 11:59 GMT+8

The world’s first digital positron emission tomography (PET ) has been developed at China's Huazhong University of Science and Technology (HUST) in Wuhan City, central China.

The medical imaging device which helps doctors detect cancer and brain diseases is expected to better fight serious diseases at a lower cost.

In early November, Professor Xie Qingguo and his team at HUST conducted full digital PET for online proton beam monitoring in Taiwan Chang Gung Memorial Hospital, which has the largest and most advanced proton radiotherapy center in Asia.

“This is the first time in human history that we monitored how the proton produced oxygen-15 on a rat. It has proven two things about digital PET: To help the proton knife locate where to hit and where it actually hits,” said Professor Xie.

The full clinical digital PET is currently in the process of installment at the Affiliated Hospital of Zhongshan University in Guangzhou. It has begun to carry out the China Food and Drug Administration clinical trials.

The formal starting up of the first digital PET will take place in early 2018.

China’s Self-Developed Medical Imaging Device PET/CT Enters Final Clinical Trial
DOU SHICONG
DATE: FRI, 05/04/2018 - 14:28 / SOURCE:YICAI

China’s Self-Developed Medical Imaging Device PET/CT Enters Final Clinical Trial

(Yicai Global) May 4 -- The world’s first fully-digital PET/CT has entered the final phase of clinical tests. PET/CT is a new type of medical imaging device that combines positron emission tomography with computed tomography, two diagnosis and treatment technologies.

A team led by Prof. Xie Qingguo of Huazhong University of Science and Technology in Wuhan, china's central Hubei province developed the device.

The First Affiliated Hospital of Sun Yat-sen University and Sun Yat-sen University Cancer Center are soliciting volunteers from the public to clinically test the equipment’s safety and efficacy during imaging diagnosis, Chinese Science News reported yesterday. After 120 cases of clinical trials conclude, registration documents will be submitted to relevant authorities.

The new PET/CT device is fully digital and able to precisely sample. It can detect tumors earlier and more accurately than conventional PET/CT devices. It also finds wide use in early detection of senile dementia and Alzheimer's.

The five-year survival rate of Chinese cancer patients is a mere 31 percent, less than half of that in the US. This low ratio is in part to blame on delayed detection and treatment, and the PET/CT device can significantly improve the capability of early cancer detection through its advantages in imaging performance, noted Zhang Xiangsong, director of nuclear medicine department of the First Affiliated Hospital, Sun Yat-sen University.

Xie’s team started research into fully-digital PET/CT in 2001 and developed the new device in 2016, which solved the technical problem of the inability of traditional PET devices to digitize scintillating pulse signals, and thus it significantly reduces detection time and costs.

 

[JSCh]

NEWS 03 MAY 2018
Water filter inspired by Alan Turing passes first test
Membrane's structure predicted in mathematician's lone biology paper.

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Alan Turing, pictured in a slate sculpture by Stephen Kettle, is known as a computer scientist and codebreaker, but also made forays into mathematical biology.Credit: Steve Meddle/REX/Shutterstock

Researchers in China have developed a filter that removes salt from water up to three times as fast as conventional filters. The membrane has a unique nanostructure of tubular strands, inspired by the mathematical-biology work of codebreaker Alan Turing.

The filter is the most finely constructed example of the mathematician’s ‘Turing structures’ yet, and their first practical application, say researchers. “These 3D structures are quite extraordinary,” says Patrick Müller, a systems biologist at the Friedrich Miescher Laboratory in Tübingen, Germany. The filter’s tubular strands, just tens of nanometres in diameter, would be impossible to produce by other methods, such as 3D printing, he says. The work is published on 3 May in Science.

British mathematician Alan Turing is best known for his codebreaking exploits for the UK government during the Second World War, and as the father of computer science and artificial intelligence. But he also produced a seminal work in the then-nascent field of mathematical biology in 1952, just two years before his death.

In it, he proposed a mathematical model for a process by which the cells of an embryo might begin to form structures — limbs, bones and organs. In this process, two substances continuously react with each other, but diffuse through their container at very different rates. The quicker-diffusing reactant — called the inhibitor — pushes back against the slower one, called the activator, effectively corralling the resulting product into a pattern of spots or stripes. (The terminology was coined by biologists Hans Meinhardt and Alfred Gierer, who independently formulated an equivalent theory in 1972.)

Spotting patterns

Whether such a process actually occurs at a cellular level has been hotly debated, says Müller. But this reaction-diffusion behaviour has been invoked to explain patterns in nature and society, including zebra stripes, sand ripples and the movements of financial markets.

So far, however, attempts to synthesize such structures in the lab have mostly been limited to 2D patterns.

A team led by material scientist Lin Zhang of Zhejiang University in Hangzhou, China, set out to create a 3D Turing structure out of a polyamid, a material similar to nylon, formed by a reaction between the chemicals piperazine and trimesoyl chloride. In a conventional process, trimesoyl chloride diffuses faster than piperazine, but the difference is not big enough to produce a Turing structure. Zhang’s trick was to add polyvinyl alcohol to the piperazine, further lowering its diffusion rate and allowing it to act as the activator to the trimesoyl chloride’s inhibitor.

The result is a rough, porous mesh with a nanostructure resembling a Turing pattern that can be seen under an electron microscope. The team was able to produce variants showing both dots and tubes — the two types of self-organizing structure predicted by Turing’s model.

Dot-based and tube-based Turing-type membranes, seen under a scanning electron microscope.Credit: Z. Tan et al./Science

The researchers were elated to produce the Turing structures, says Zhang. But they were more surprised when they found that their membranes functioned as efficient water filters — surpassing conventional nylon-like filters in some respects.

The filter’s tubular structure gives it a larger surface area compared to conventional filters, which increases the flow of water through the membrane, says Ho Bum Park, a membrane scientist at Hanyang University in Seoul. It’s an improvement on conventional membrane structures, which resemble a series of ridges and valleys, he says. “It’s a really smart approach.”

In tests performed by Zhang’s group, one pass through the tubular Turing filter reduced the table-salt content of a slightly saline solution by half. It also filtered out other salts: magnesium chloride by more than 90%; and magnesium sulfate, or Epsom salt, by more than 99%. The authors say that 1 square metre of filter can process up to 125 litres of water per hour while being pumped at a relatively low pressure of around 5 times atmospheric pressure. This is as much as three times as fast as typical commercial filters, Zhang says. The Turing filter could be used for purifying brackish water and industrial wastewater, says Zhang.

Other barriers

Although the membrane is effective at removing some impurities, Park says that its relatively low effectiveness eliminating table salt could make it impractical for desalinating seawater. Zhang says could be used to pretreat seawater in desalination plants, with the table salt removed via conventional methods, such as reverse osmosis.

Müller says that if the technique can be generalized, such tubular structures could also have applications in regenerative medicine — for instance, producing artificial veins or bones. “And once you know how to make tubules, maybe you can arrange these things into higher-order structures — maybe even organs,” he says. “Now that would be the dream application.”

But Müller also notes that because of the uncertainty in predicting whether such structures will form, they could be difficult to reproduce in other materials.

Even if that proves to be the case, the membrane is a tribute to the impact of Turing’s 1952 paper, says Zhang. “It’s a part of his legacy.”

doi: 10.1038/d41586-018-05055-7


Water filter inspired by Alan Turing passes first test | Nature

Zhe Tan, Shengfu Chen, Xinsheng Peng, Lin Zhang, Congjie Gao. Polyamide membranes with nanoscale Turing structures for water purification. Science 360, 518–521 (2018). DOI: 10.1126/science.aar6308.​

 

[JSCh]

Chinese, American scientists make super-tough carbon sheets at low temperature
Source: Xinhua 2018-05-08 04:15:42

WASHINGTON, May 7 (Xinhua) -- An international research team led by Chinese and American scientists has developed high-strength, super-tough sheets of carbon that can be inexpensively fabricated at low temperatures.

The team reported on Monday in the Proceedings of the National Academy of Sciences the sheets they made by chemically stitching together platelets of graphitic carbon, which is similar to the graphite found in the soft lead of an ordinary pencil.

The fabrication process resulted in a material whose mechanical properties exceed those of carbon fiber composites that are currently used in diverse commercial products.

"These sheets might eventually replace the expensive carbon fiber composites that are used for everything from aircraft and automobile bodies to windmill blades and sports equipment," said Ray Baughman, professor of chemistry at University of Texas.

Carbon fiber composites are expensive in part because carbon fibers are produced at extremely high temperatures, which can exceed 2,500 degrees Celsius.

"In contrast, our process can use graphite that is cheaply dug from the ground and processed at temperatures below 45 degrees Celsiu," said Cheng Qunfeng, professor of chemistry at China's Beihang University.

According to Cheng, graphite consists of platelets made up of stacked layers of graphene. Graphene is simply a single layer of carbon atoms, arranged in a pattern that looks like a chicken wire mesh fence, where each hexagon in the mesh is formed by six carbon atoms.

"While scientists can continuously make large sheets of graphene by high-temperature processing, and have shown these sheets to have remarkable strength, it is impractical to make thick plates of graphite by merely stacking large-area graphene sheets," Cheng said. "One would need to stack about 150,000 graphene sheets to make a graphite sheet having about the thickness of a human hair."

The researchers found inspiration in natural nacre, also known as mother-of-pearl, which gives some seashells their strength and toughness. Nacre is composed of parallel platelets that are bound together by thin layers of organic material, similar to the way bricks in a wall are held together by mortar.

"Instead of mechanically stacking large-area graphene sheets, we oxidize micron-size graphite platelets so that they can be dispersed in water, and then filter this dispersion to inexpensively make sheets of oriented graphene oxide," Baughman said. "This process is akin to hand-making sheets of paper by filtering a slurry of fibers."

"At this stage, the sheets are neither strong nor tough, meaning they cannot absorb much energy before rupturing," said Baughman.

"The trick we use is to stitch together the platelets in these sheets using sequentially infiltrated bridging agents that interconnect overlapping neighboring platelets, and convert the oxidized graphene oxide to graphene," said Baughman.

The key to this advance is that the bridging agents separately act via formation of covalent chemical bonds and van der Waals bonds, according to Baughman.

Sheets that incorporated the bridging agents were 4.5 times stronger and 7.9 times tougher than agent-free sheets, said Wan Sijie, a Beihang University PhD student.

"While sheets of expensive carbon fiber composites can provide a similar strength in all sheet-plane directions, the energy that they can absorb before fracture is about one-third that of our sequentially bridged graphene sheets," said Wan.

"Because our sheets are fabricated at low temperatures, they are low cost. In addition to exhibiting high sheet strength, toughness and fatigue resistance, they have high electrical conductivity and are able to shield against electromagnetic radiation," said Wan.

Sijie Wan, Yuchen Li, Jiuke Mu, Ali E. Aliev, Shaoli Fang, Nicholas A. Kotov, Lei Jiang, Qunfeng Cheng, and Ray H. Baughman. Sequentially bridged graphene sheets with high strength, toughness, and electrical conductivity. PNAS (2018). DOI: https://doi.org/10.1073/pnas.1719111115​

 

[JSCh]

PUBLIC RELEASE: 8-MAY-2018
Theory for one type of superconductor solves puzzle in another
'Orbital-selective pairing' theory applied to first 'heavy fermion' superconductor

RICE UNIVERSITY

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This is Qimiao Si. CREDIT: Jeff Fitlow/Rice University

HOUSTON -- (May 8, 2018) -- A 2017 theory proposed by Rice University physicists to explain the contradictory behavior of an iron-based high-temperature superconductor is helping solve a puzzle in a different type of unconventional superconductor, the "heavy fermion" compound known as CeCu2Si2.

An international team from the U.S., China, Germany and Canada reported the findings this week in the Proceedings of the National Academy of Sciences (PNAS). The study focused on a cerium, copper and silicon composite whose strange behavior in 1979 helped usher in the multidisciplinary field of quantum materials.

That year, a team led by Max Planck Institute's Frank Steglich, a co-author on the PNAS paper, found that CeCu2Si2 became a superconductor at extremely cold temperatures. The mechanism of superconductivity couldn't be explained by existing theory, and the finding was so unexpected and unusual that many physicists initially refused to accept it. The 1986 discovery of superconductivity at even higher temperatures in copper ceramics crystalized interest in the field and came to dominate the career of theoretical physicists like Rice's Qimiao Si, a PNAS study co-author and the Harry C. and Olga K. Wiess Professor of Physics and Astronomy.

Si, whose decadeslong collaboration with Steglich has led to almost two dozen peer-reviewed studies, said, "In my wildest dreams, I had not thought that the theory that we proposed for the iron-based superconductors would come back to the other part of my life, which is the heavy-fermion superconductors."

Heavy fermions, like high-temperature superconductors, are what physicists call quantum materials because of the key role that quantum forces play in their behavior. In high-temperature superconductors, for example, electrons form pairs and flow without resistance at temperatures considerably warmer than those needed for conventional superconductivity. In heavy fermions, electrons appear to be thousands of times more massive than they should.

In 2001, Si, who also directs the Rice Center for Quantum Materials (RCQM), offered a pioneering theory that these phenomena arise at critical transition points, tipping points where changes in pressure or other conditions bring about a transition from one quantum state to another. At the tipping point, or "quantum critical point," electrons can develop a kind of split personality as they attempt to straddle the line between states.

The case of superconductivity illustrates how this can play out. In a normal copper wire, electrical resistance arises when flowing electrons jostle and bump against atoms in the wire. Each bump costs a small amount of energy, which is lost to heat. In superconductors, the electrons avoid this loss by pairing up and flowing in unison, without any bumps.

Because electrons are among the most antisocial of subatomic particles, they repel one another and pair up only in extraordinary circumstances. In the case of conventional superconductors, tiny variations in the spacing between atoms in a supercooled wire can coax the electrons into a marriage of convenience. The mechanism in unconventional superconductors is different.

"Our unifying understanding is that if two electrons work really hard to repel one other, there can still be an attractive force," Si said. "If I am moving because I don't like being close to you, and you are doing the same, and yet we cannot be too far apart, it becomes a kind of dance. The pairs in high-temperature superconductors move in relation to one another, not unlike two dance partners that spin, even as they move together across the dance floor."

The 2017 theory put forward by Si and then-graduate student Emilian Nica, now a postdoctoral research associate at the University of British Columbia's Quantum Materials Institute, posited that selective pairing within atomic orbitals could explain some puzzling experimental results from some of the highest-temperature superconductors, alkaline iron selenides.

Some experiments had shown that the pairs in alkaline iron selenides behaved as if they had an angular momentum of zero, which physicists refer to with the term s-wave, while other experiments indicated the pairs had an angular momentum of two, which physicists call d-wave. This difference is profound because angular momentum is a fundamental identifier for electrons. Just as apples and oranges are found in different bins at the grocery story, s-wave and d-wave pairings don't mix and are found in different materials.

"What Nica's thesis introduced was that you can have a superconducting state in which electron pairs associated with one orbital of a subshell are very different from those of another closely related orbital in the same subshell because they have an opposite sign," Si said.

"The reason we proposed this multi-orbital pairing state was because measurements of some things, like magnetic responses, would show that the alkaline iron selenides had canonical d-wave features, and other measurements, like angular resolved photo emission, revealed attributes associated with s-wave superconductors.

"The experiments in the iron-based superconductor had already been done, and we offered an explanation, a pairing state that was both stable and robust, and yet had all these seemingly contradictory properties that were experimentally observed."

When 2017 experiments in Japan revealed some puzzling properties in CeCu2Si2, Si told Steglich that the orbital-selective theory might be able to account for them. Together, they joined forces with the experimental team of physicist Huiqiu Yuan, deputy director of the Center for Correlated Matter at Zhejiang University in Hangzhou, China, to test the idea.

Si and Nica's theory predicted that experiments would reveal a specific set of seemingly contradictory measurements from CeCu2Si2, provided the material could be cooled to a temperature even colder than the tipping point that brings about superconductivity. Yuan's group performed the experiments and confirmed the prediction.

"Historical evidence has always been that the pairing in this material is d-wave," Nica said. "But the experiments confirmed that indeed, despite all the overwhelming evidence that it is d-wave, it has a feature called 'fully opened gaps' that is normally associated with s-wave superconductors. Ours is the only theory offered so far that can account for this."

Si said, "It's enormously satisfying on several levels. One is that while condensed-matter physics offers many materials that can host fascinating properties, we ultimately are seeking unifying principles, especially as theorists. I have actively searched for these unifying principles for years, but we weren't actively seeking a unifying explanation when we proposed this theory. To see it applied, to such effect, in another completely unexpected setting was a real surprise."


Theory for one type of superconductor solves puzzle in another | EurekAlert! Science News

Guiming Pang, Michael Smidman, Jinglei Zhang, Lin Jiao, Zongfa Weng, Emilian M. Nica, Ye Chen, Wenbing Jiang, Yongjun Zhang, Wu Xie, Hirale S. Jeevan, Hanoh Lee, Philipp Gegenwart, Frank Steglich, Qimiao Si, and Huiqiu Yuan. Fully gapped d-wave superconductivity in CeCu2Si2. PNAS, 2018 DOI: 10.1073/pnas.1720291115​

 

[JSCh]

Chinese Scientists Generate a High-quality Wheat A Genome Sequence
May 09, 2018

Bread wheat (Triticum aestivum L.), feeding more than 35% human population and providing about 20% of calories and proteins consumed by humans, is a globally important crop due to its enhanced adaptability to a wide range of climates and improved grain quality for the production of baker's flour.

Due to its complex polyploidy nature (hexaploid, containing A, B and D three subgenomes) and large genome size (17 Gb), the genetic and functional analysis of bread wheat is extremely challenging.
The A genome, originates from the diploid wild einkorn wheat Triticum urartu with a genome size about 5 Gb, is the basic genome of bread wheat and other polyploidy wheats. It plays a central role in wheat evolution, domestication and genetic improvement.

To illustrate the genomic structures of wheat, the wheat genome research team of State Key Laboratory of Plant Cell and Chromosome Engineering, Institute of Genetics and Developmental Biology, Chinese Academy of Sciences, collaborating with the Genomic Sequencing and Analysis Laboratory of the institute, BGI Shenzhen and Keygene in the Netherland, generated a high-quality genome sequence of T. urartu by combining BAC-by-BAC sequencing, single molecule real-time whole-genome shotgun sequencing and next-generation mapping technologies.

The scientists produced seven chromosome-scale pseudomolecules, predicted 41,507 protein-coding genes, and presented an evolution model of T. urartu chromosomes.
Then they found that the collinearity originated from the ancient genome duplications in T. urartuwere strongly disrupted because of extensive amplifications of transposable elements and widespread gene loss, compared to rice, sorghum and Brachypodium.

Comparative analysis with the A, B and D subgenomes of bread wheat also showed that four large chromosomal structure variations occurred during wheat evolution.

Population genomics analysis revealed that T. urartu accessions from the Fertile Crescent formed three distinct groups with different adaptation to high altitude and biostress, such as powdery mildew disease.

The genome sequence of T. urartu provides a diploid reference for the analysis of polyploidy wheat genomes, and is a valuable resource for systematically studying the genome evolution and genetic variations in wheat and related grasses. It promises to facilitate the discovery of genes conferring important traits for the genetic improvement of wheat to meet the future challenges of global food security and sustainable agriculture.

The research results were published on line in a paper in Nature with the title "Genome sequence of the progenitor of wheat A subgenomeTriticum urartu".

Triticum urartu, the progenitor of wheat A subgenome (Image by IGDB)
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Chinese Scientists Generate a High-quality Wheat A Genome Sequence---Chinese Academy of Sciences

Hong-Qing Ling, Bin Ma, Xiaoli Shi, Hui Liu, Lingli Dong, Hua Sun, Yinghao Cao, Qiang Gao, Shusong Zheng, Ye Li, Ying Yu, Huilong Du, Ming Qi, Yan Li, Hongwei Lu, Hua Yu, Yan Cui, Ning Wang, Chunlin Chen, Huilan Wu, Yan Zhao, Juncheng Zhang, Yiwen Li, Wenjuan Zhou, Bairu Zhang, Weijuan Hu, Michiel J. T. van Eijk, Jifeng Tang, Hanneke M. A. Witsenboer, Shancen Zhao, Zhensheng Li, Aimin Zhang, Daowen Wang & Chengzhi Liang. Genome sequence of the progenitor of wheat A subgenome Triticum urartu. Nature (2018). DOI: 10.1038/s41586-018-0108-0​

 

[JSCh]

Ultra-strong 0.12 mm sheet glass mass produced in China
ECNS App Download

A piece of glass sheet about 0.12 millimeter thick was produced by the Glass Research Institute. (Photo/Video screenshot from CCTV)

(ECNS) -- A Chinese research institute has created super-thin, ultra-strong sheet glass that can resist the impact force of a car running at 150 kilometers an hour, China Central Television reported.

Created by the Glass Research Institute in Bengbu City, a unit of the engineering technical platform of China National Building Material Co., Ltd, the glass is only 0.12 millimeter thick — roughly as thick as a standard A4-sized piece of paper.

In an experiment led by leading researcher Cao Xin, a 55-gram steel ball was dropped from one meter to hit the glass, equivalent to the impact force made by a car at 150kph, and the glass remained intact.

The sheet glass, which came off the product line in April, is the thinnest one mass-manufactured using the float process, according to Cao.

Cao said the ultra-thin glass can be used widely in the electronic information sector, such as for screens for cellphones, computers and TVs. He said his next goal is to mass produce sheet glass at 0.1 millimeter thick.

Led by chief scientist Peng Shou, the research institute has made a series of strides in recent years, making 0.33-millimeter sheet glass in June 2014, 0.15-millimeter in April 2016 and now 0.12-millimeter.

 

[JSCh]

PUBLIC RELEASE: 10-MAY-2018
The BIG Bell Test
Global physics experiment challenges Einstein with the help of 100,000 volunteers

UNIVERSITY OF SCIENCE AND TECHNOLOGY OF CHINA

An image about the BIG Bell Test. CREDIT: The BIG Bell Test Collaboration

• Simultaneous experiments on five continents challenge Einstein's principle of local realism.
• Participants contributed to the experiment generating more than 90 million bits, unpredictably choosing among measurements to escape a paradox known as the "freedom-of-choice loophole".
• The study has been published in Nature.

On November 30th, 2016, more than 100,000 people around the world contributed to a suite of first-of-a-kind quantum physics experiments known as The BIG Bell Test. Using smartphones and other internet-connected devices, participants contributed unpredictable bits, which determined how entangled atoms, photons, and superconducting devices were measured in twelve laboratories around the world. Scientists used the human input to close a stubborn loophole in tests of Einstein's principle of local realism. The results have now been analysed, and are reported in this week's Nature.

In a Bell test (named for the physicist John Stewart Bell), pairs of entangled particles such as photons are generated and sent to different locations, where particle properties such as the photons' colours or time of arrival are measured. If the measurement results tend to agree, regardless of which properties we choose to measure, it implies something very surprising: either the measurement of one particle instantly affects the other particle (despite being far away), or even stranger, the properties never really existed, but rather were created by the measurement itself. Either possibility contradicts local realism, Einstein's worldview of a universe independent of our observations, in which no influence can travel faster than light.

The BIG Bell Test asked human volunteers, known as Bellsters, to choose the measurements, in order to close the so-called "freedom-of-choice loophole" - the possibility that the particles themselves influence the choice of measurement. Such influence, if it existed, would invalidate the test; it would be like allowing students to write their own exam questions. This loophole cannot be closed by choosing with dice or random number generators, because there is always the possibility that these physical systems are coordinated with the entangled particles. Human choices introduce the element of free will, by which people can choose independently of whatever the particles might be doing.

Led by ICFO-The Institute of Photonic Sciences, in Barcelona, the BIG Bell Test recruited participants worldwide to contribute unpredictable sequences of zeros and ones (bits) through an online video game. The bits were routed to state-of-the-art experiments in Brisbane, Shanghai, Vienna, Rome, Munich, Zurich, Nice, Barcelona, Buenos Aires, Concepción Chile and Boulder Colorado, where they were used to set the angles of polarizers and other laboratory elements to determine how entangled particles were measured.

Participants contributed with more than 90 million bits, making possible a strong test of local realism, as well as other experiments on realism in quantum mechanics. The obtained results strongly disagree Einstein's worldview, close the freedom-of-choice loophole for the first time, and demonstrate several new methods in the study of entanglement and local realism.

Each of the twelve labs around the world carried out a different experiment, to test local realism in different physical systems and to test other concepts related to realism.

The CAS-USTC team, led by Prof. Jian-Wei Pan and Prof. Qiang Zhang, works to explore the Bell's inequality with partial perfect randomness input. Analysing the random numbers contributed by Bellsters, we may find the human random number are not perfectly random, and tend to produce patterns. However, the human generated randomness is highly attractive because of the element of human free will. True randomness, which is not controlled by hidden variables, exists in between the human choices. Remarkably, it is able to say how well the hidden variable would have to control the human choices. This is made possible by using a special type of Bell inequality, the measurement dependent local (MDL) inequality. In the experiment, a 780 nm pump laser focused on a periodically poled potassium titanyl phosphate (PPKTP) crystal to create photon pairs at 1560 nm via spontaneous parametric down conversion. The down-converted photon pairs interfere at the polarizing beam splitter (PBS) in a Sagnac based setup to create entangled pairs. The entangled state is adjusted to be a special non-maximum entangled state for the inequality. The photon pairs are then sent to two measurement stations that are ~90 meters away for measurement. This spatial separation makes sure the measurement in Alice's lab will not affect that in Bob's lab, and vice versa. The random numbers contributed by Bellsters control the Pockels cell to set the measurement basis for each pair of photons. The photons are finally detected with superconducting nanowire single-photon detectors (SNSPDs, produced by the group led by Dr. Lixing You from CAS-SIMIT). The violation of the MDL Bell inequality gives the bound of the input human randomness to rule out local realism. With around 80 Mb random numbers contributed by Bellsters, the MDL Bell inequality violation is decided to be l = 0.10 ± 0.05.

Jian-Wei Pan, Professor at CAS-USTC: "Although there are numerous Bell test experiments, the "free will" loophole is still not closed. This experiment is a very interesting and important try. In the future, with the help of space station, one may close both "collapse locality" and "free will" loopholes in one experiment."

Carlos Abellán, researcher at ICFO and instigator of the project: "The BIG Bell Test was an incredibly challenging and ambitious project. It sounded impossibly difficult on day zero, but became a reality through the efforts of dozens of passionate scientists, science communicators, journalists and media, and especially the tens of thousands of people that contributed to the experiment during November 30th, 2016."

Morgan Mitchell, leader of the BBT project and ICREA Professor at ICFO: "What is most amazing for me is that the argument between Einstein and Niels Bohr, after more than 90 years of effort to make it rigorous and experimentally testable, still retains a human and philosophical element. We know that the Higgs boson and gravitational waves exist thanks to amazing machines, physical systems built to test the laws of physics. But local realism is a question we can't fully answer with a machine. It seems we ourselves must be part of the experiment, to keep the Universe honest."

The BIG Bell Test team once again would like to thank the thousands of participants who so generously and enthusiastically contributed to this initiative. Without this essential contribution, the experiment would have never been possible.

###​

Reference: https://www.nature.com/articles/s41586-018-0085-3

Participating Institutions

The twelve labs that ran experiments on November 30th of 2016 were:

• CQC2T -- Griffith University and EQuS (Brisbane-Australia),
• University of Queensland (Brisbane-Australia),
• The node CEFOP/Department of Electrical Engineering of the Universidad de Concepción (Concepción-Chile), together with the Department of Electrical Engineering - Linköping University, the University of Sevilla and the Dipartimento di Fisica--Sapienza Università di Roma,
• The Quantum Information Lab of the Dipartimento di Fisica - Sapienza Università di Roma with the International Institute of Physics del Federal University of Rio Grande do Norte (Brazil),
• CAS --University of Science and Technology of China (Hefei-China),
• CITEDEF/Universidad de Buenos Aires (Buenos Aires),
• ICFO (Barcelona),
• IQOQI/OEAW (Vienna-Austria),
• LMU-Ludwig-Maximilian University (Munich),
• LPMC -- Université Nice/CNRS (Nice-France),
• NIST (Boulder- USA),
• QUDEV- ETH Zurich (Zurich).

The BIG Bell Test | EurekAlert! Science News

 

[JSCh]

Thermal spring with rare gas found in Tibet
Source: Xinhua| 2018-05-10 16:37:26|Editor: ZX


BEIJING, May 10 (Xinhua) -- A thermal spring rich in the rare gas helium has been identified in Tibet Autonomous Region, and has the potential to be exploited, the Science and Technology Daily reported Thursday.

Researchers from China and the United States believe the helium concentration could be as high as 1.11 percent in some thermal-spring gas in Ali prefecture in Tibet, the newspaper quoted a source of the Institute of Tibetan Plateau Research with the Chinese Academy of Sciences (CAS) as saying.

If helium concentration exceeds 0.1 percent it can be be industrially utilized.

Helium is a colorless and odorless inert gas with a low boiling point. It has been widely used in aerospace, low temperature superconductivity, the nuclear industry and scientific research. The concentration of helium in the atmosphere is only 5.2 parts per million, making the cost of its extraction very high.

In 2001, Chinese researchers with the Institute of Geology and Geophysics of the CAS discovered thermal-spring gas with a high concentration of helium at an altitude of 4,340 meters, during a geothermal study. They and U.S. researchers with Stanford University in July gathered the gas samples and recently revealed the test results.

China has low levels of helium, and has relied on imports for a long time. There is only one natural gas field in China that can realize the industrial exploitation of helium.

 

[JSCh]

China makes breakthrough in stem cell culture equipment
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(Photo/CCTV)​

(ECNS) -- Chinese researchers announced on Tuesday a breakthrough in developing the world's first large scale, fully automated and standardized pluripotent stem cell induction and culture equipment.

The equipment, developed by the Guangzhou Institute of Biomedicine and Health and the Chinese Academy of Science, passed review and was accepted on Tuesday. The research is listed as a key state science and technology project.

Chinese researchers overcame eight critical technical challenges in four years to achieve a number of innovative results, reported China Central Television.

The system can effectively address a range of issues arising in traditional laboratory work such as low efficiency, high labor and time requirements, and poor safety, in developing pluripotent stem cell cultures that are in great demand for various research across the globe.

The system greatly reduces costs and improves quality, said CCTV.

Stem cells can self-renew or multiply while maintaining the potential to develop into other types of cells. They are valuable research tools and might in future be used to treat a wide range of ailments.

 

[JSCh]

Bioprinting builds 3D model of a brain tumour
15 May 2018
Belle Dumé

Patients who are newly diagnosed with high-grade gliomas (GBMs), one of the most aggressive brain tumours, only have a median survival time of around 15 months – reducing to just 5–7 months for recurrent tumours. Glioma stem cells are thought to be at the root of these poor outcomes, so researchers are focusing on therapies that could target these cells. An important first step is to develop realistic models that will enable scientists to study the biology of glioma stem cells and to investigate the resistance of GBMs to chemotherapy.

To date, researchers have mainly exploited 2D monolayers of glioma lines as a model for the tumour, providing a way for studying how gliomas evolve and how they react to anti-cancer drugs. However, this model fails to take into account the 3D environment of the tumour, and it doesn’t allow researchers to study other significant factors such as cell–cell and cell–matrix interactions, spatio-temporal signalling and metabolic gradients. Unfortunatel,y this means that most anti-glioma drugs that proved to be effective in vitro have failed miserably in clinical trials.

Now, a team of researchers led by Tao Xu and Qin Lan from Soochow University, Tsinghua University and the Tsinghua-Berkeley Shenzhen Institute, all in China, and Medprin Biotech GmbH in Germany, have turned to 3D bioprinting to create a glioma stem-cell model. “Our work shows that we can use bioprinting technology to build 3D glioma models,” explains team member Xingliang Dai. “This is just beginning of our studies on the glioma microenvironment.”


--> Bioprinting builds 3D model of a brain tumour – Physics World

 

[JSCh]

Shanghai sets up pioneering brain science center
Source: Xinhua| 2018-05-15 17:21:48|Editor: ZX


SHANGHAI, May 15 (Xinhua) -- Shanghai has launched a research center focusing on brain science and brain-inspired intelligence, fields closely linked with artificial intelligence (AI).

Brain science and brain-inspired intelligence studies can be applied in improving the diagnosis and prevention of brain diseases, and developing brain-inspired AI algorithms and hardware.

The move follows the establishment of a similar center in Beijing in March and comes as China is increasing its efforts to draw top talent in these fields by providing funding and facilities.

The new center is located in Zhangjiang Laboratory, a leading science facility co-established by Chinese Academy of Sciences (CAS) and Shanghai municipal government in September.

"The center will work in the most cutting-edge fields to produce world-class outcomes, " said Bai Chunli, head of the CAS. "We will also employ top scientists from all over the world."

The center is also creating a more effective management system, as well as salary and incentive mechanisms that can compete with international institutions, Bai added.

In early 2016, the CAS set up the Center for Excellence in Brain Science and Intelligence Technology, combining resources from 20 research institutions, including 80 top laboratories, across the country.

China is also launching "China Brain Project," a 15-year project approved in 2016, following related projects set up in the United States, European Union, and Japan.

 

[JSCh]

Scientists make quantum leap with simple water molecule
By ZHANG ZHIHAO | China Daily | Updated: 2018-05-15 07:16

In a simulation using atomic force microscopy, four water molecules bond with a sodium ion one by one (A to D). A fifth water molecule (white spot at lower left) bonds with the hydrated sodium ion. As one sodium ion can only bond with four water molecules tightly at most, the fifth one can only bond outside. (E) An artist's rendering of a hydrated sodium ion with three water molecules. (F)

Chinese scientists have become the first to directly observe the atomic structure of a hydrated sodium ion-the basic chemical makeup of seawater.

The technology can be used to study other water-based liquids, opening new avenues for molecular and materials sciences, experts said on Monday in the science journal Nature.

It is the first time scientists have been able to visualize the atomic structure of hydrated ions in their natural environment since the notion was proposed more than a hundred years ago.

The same team of scientists also discovered that exactly three water molecules are needed to allow a single sodium ion to travel 10 to 100 times faster than other ion hydrates-a process that could lead to more efficient ion batteries, anti-corrosion coatings and seawater desalination plants, according to the Nature article.

Water is the most plentiful liquid on Earth. Its simple chemical structure-two hydrogen atoms bonded to one oxygen atom-is the basic building block of most life on Earth, said Wang Enge, a physicist and academician of the Chinese Academy of Sciences.

"But the science behind water, especially regarding its structure and interaction with other chemicals, is extremely hard and not well understood," Wang said. In 2005, the journal Science listed the structure of water as one of the most compelling scientific puzzles, despite a century's worth of research having been done.

Since the late 19th century, scientists have been studying ion hydration, a process in which water dissolves soluble materials such as sodium chloride, or salt. Although the process is extremely common in nature, exactly how it works at an atomic level has remained a mystery.

"The main reason for water's complexity is its simplicity," said Jiang Ying, a professor at Peking University's International Center for Quantum Materials, who was part of the study.

Because hydrogen atoms are so simple and small compared with the oxygen atom, the weird properties of quantum mechanics start to interfere with experiments and make them less predictable, he said.

"Therefore, it is crucial for scientists to directly see how water interacts with other materials at an atomic level." By using new atomic force microscopy developed by Chinese scientists, it's possible "to see even the smallest changes in a single water molecule's structure around the ions", Jiang said.

Scientists found that three water molecules surrounding a single sodium ion can travel exceptionally fast on a sodium chloride molecule's surface. This "sublime phenomenon" can occur at room temperature, but also applies with other chemical ions such as potassium ions-one of the key ions necessary for neural cell communication.

"Although the magic number for each type of ion might be different, the phenomenon is a game changer for ion-related fields," he said. For example, engineers can alter the flow speed of lithium ions in batteries to make them charge faster or store more power.

Scientists can also create special filter systems that can change the number of water molecules surrounding an ion, thus speeding up or reducing the filtering speed according to specific needs.

This discovery also allows scientists to have a better understanding of how cells communicate with each other by exchanging ions through channels on their membranes, Jiang said.

This has potentially profound scientific implications for future applications in biology and medicine, he said, adding that two Nobel Prizes were given to research related to ion channels in the last two decades-one for their discovery in 1991 and the other for their mechanisms in channeling water in 2003.

Jinbo Peng, Duanyun Cao, Zhili He, Jing Guo, Prokop Hapala, Runze Ma, Bowei Cheng, Ji Chen, Wen Jun Xie, Xin-Zheng Li, Pavel Jelínek, Li-Mei Xu, Yi Qin Gao, En-Ge Wang & Ying Jiang. The effect of hydration number on the interfacial transport of sodium ions. Nature (2018). DOI: 10.1038/s41586-018-0122-2​