China Science & Technology Forum

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Chinese researchers contribute to 11 pct of Nature papers
Source: Xinhua| 2018-03-25 01:36:26|Editor: Mu Xuequan


GUANGZHOU, March 24 (Xinhua) -- China has become a larger contributor to original research papers on Nature, the Greater China subsidiary of the scientific journal's publisher Springer Nature said Saturday.

Chinese researchers published more than 90 original research papers on Nature in 2016, accounting for about 11 percent of all, compared with 0.4 percent in 1997, it said.

China was the world's second largest contributor to high-quality scientific research papers, only after the United States, according to the Nature Index 2016 which tracked 68 scientific journals including Nature, Science and Cell.

Nature held an international symposium on women and children's health in Guangzhou, capital of south China's Guangdong Province, between Thursday and Saturday.

 

[JSCh]

China fires up next-generation neutron-science facility
Beam generator puts country in elite company for doing experiments in materials science and other fields.

• David Cyranoski
• 14 November 2017

Jin Liwang/Xinhua via ZUMAPRESS​

Engineers work on an instrument at the China Spallation Neutron Source in Dongguan.

China is revving up its next-generation neutron generator and will soon start experiments there. That will lift the country into a select group of nations with facilities that produce intense neutron beams to study the structure of materials.

The China Spallation Neutron Source (CSNS) in Dongguan, a 2.2-billion-yuan (US$331-million) centre, will allow the country’s growing pool of top-notch physicists and material scientists, along with international collaborators, to compete in multiple physics and engineering fields. Its designers also hope that the facility will lead to commercial products and applications ranging from batteries and bridges to aeroplane engines and cancer therapy.

“It is not only a big step forward for Chinese scientists, but also a significant event for the international scientist community,” says Wang Xun-Li, a physicist at the City University of Hong Kong who has been involved in planning the facility.

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Beam bombardment
Spallation neutron sources produce neutrons by slamming protons onto a metal target — CSNS uses tungsten. They are more cost effective and safer than other methods, which use nuclear reactors to produce neutron beams. As neutrons have no charge, they can penetrate materials more easily than some other probing methods, and they are more senstive to light elements such as hydrogen, making them useful for evaluating candidate materials for fuel cells. Similar facilities exist only in the United Kingdom, United States, Japan and Switzerland, and one is under construction in Sweden.

Fujio Maekawa, a specialist in neutron sources at the Japan Proton Accelerator Research Complex in Tokaimura, says that although the CSNS delivers neutrons at a lower density than other spallation sources — which means that experiments will take longer — a planned upgrade will bring it in line with other facilities. And given their scarcity, “neutron users around the world always welcome new sources”, he says.

The CSNS will have capacity to host 20 beam lines, supplying as many instruments. Preliminary tests of its first three instruments began on 1 November. “Neutrons arrived at the samples as expected,” says Wang Fangwei, head of the neutron-science division at CSNS. Although debugging might take a couple of years, he expects the instruments to be calibrated and ready for initial experiments by the end of 2017.

Chinese physicists are eager to use the facility to analyse the underlying magnetic properties of materials, an area in which the country has significant experience. Wang Xun-Li says that several planned instruments will give scientists the chance to move to the forefront of fields such as the physics of skyrmions — vortex-like excitations in magnetic materials — and high-temperature superconductivity. “There are a whole bunch of early- to mid-career scientists who are hungry to use the facility for studying magnetism,” says Wang Xun-Li.

Global appeal
Wang Xun-Li thinks that the latest facility will encourage Chinese researchers to remain in the country instead of pursuing careers elsewhere. “In the past, it was common to see Chinese scientists go abroad for these kinds of studies,” he says.

The facility’s first instruments are also attracting international researchers. German material scientist Frank Klose says that the CSNS was a major factor when he and material scientist Christine Rehm, his wife, decided to join the new Guangdong Technion Israel Institute of Technology in Shantou, 400 kilometres east of Dongguan. Klose’s research focuses on designing data-storage devices and sensors that could be used in hydrogen-powered cars. He helped design one of the facility's instruments to investigate the magnetic properties of spintronic devices, which take advantage of the spin of electrons to store data.

But scientists contacted by Nature have raised concerns about CSNS’s location, saying that Dongguan lacks services and infrastructure, such as schools and universities, that will persuade top scientists and their families to move there. “I believe CSNS is suffering from a lack of first-grade scientists who actually are based in Dongguan,” says a researcher familiar with the facility, who asked for anonymity because of the sensitivity of the issue. Potential users have also expressed some frustration that only 3 instruments will be ready this year, despite the facility’s capacity to host 20.

But more instruments are already being built. Shenzhen's government is funding two that are expected to be ready by the end of 2019, including one designed to model high-pressure environments, such as the Earth's core. Mao Ho-Kwang, a geophysicist at the Carnegie Institution for Science in Washington DC, is keen to use it to simulate what happens to materials in high-pressure conditions. “The CSNS instruments will be a great asset for Earth, environmental and energy science, as well as physics, chemistry and material science,” says Mao. “I am very excited, and the whole neutron community is getting very excited too”.

Nature 551, 284 (16 November 2017)
doi:10.1038/nature.2017.22976​

China fires up next-generation neutron-science facility : Nature News & Comment

Spallation neutron source passes assessment, checks
chinadaily.com.cn | Updated: 2018-03-26 10:12

A spectrometer detector at the spallation neutron source in Dongguan, South China's Guangdong province. [Photo/chinanews.com]

The Institute of High Energy Physics under the Chinese Academy of Sciences said Sunday China's spallation neutron source, one of the country's most important scientific facilities in Dongguan, South China's Guangdong province, has passed assessment and checks by the CAS.

The spallation neutron source is the first of its kind in the country and the fourth worldwide and will provide intense pulsed neutron beams for scientific research. It is a significant step in the country solving problems on the frontier of science.

Construction for the SNS started in September 2011, and total investment has reached 2.3 billion yuan ($364.4 million).

​

 

[JSCh]

Shanghai launches human phenotype research project
Source: Xinhua| 2018-03-26 00:44:29|Editor: Chengcheng


SHANGHAI, March 25 (Xinhua) -- Shanghai on Sunday announced the launch of a human phenotype research project with aims to accelerate the development of precision medicine in China.

Scientists from China, Britain, Germany, the United States and Australia plan to conduct in-depth research into the interaction between phenotype and genotype, which could lead to more precise treatment of complicated human diseases such as cancer, according to Jin Li, chief scientist of the project.

Scientists believe that phenotype, the observable properties of human body, is produced by the interaction of the genotype and the environment.

The international human genome project has cracked the "gene book" of human body. However, human diseases are not caused solely by the factor of genes, said Jin, vice president of Fudan University.

The first phase of the project is aimed at understanding how cancer and other complicated diseases develop by addressing the the specific relationships and internal mechanisms between genes and phenotypes, said Jin.

The project will produce the first reference atlas of the full phenotypic group of healthy Chinese, which will include 20,000 measurements.

 

[JSCh]

Chinese scientists design bee-inspired morphing aircraft
Source: Xinhua| 2018-03-24 23:41:14|Editor: Yamei


BEIJING, March 24 (Xinhua) -- Chinese scientists are designing a morphing aircraft that takes its inspiration from bees, according to the China Academy of Launch Vehicle Technology (CALT).

The morphing airplane is expected to reduce resistance during flight and be more fuel-efficient, CALT said on its official website.

According to the designer Hu Guotun, morphing aerospace aircraft travel through the atmosphere to space before returning to the atmosphere. In the process of re-entry, the aircraft will use its own inertial glide for a period of time. Minimizing flight resistance is vital for saving fuel.

"We have drawn inspiration from the bee's abdomen structure, which allows the bee to flex freely and control the direction of flight," said Hu.

Based on the bee's flexible abdomen structure, CALT designed a morphing nose cone for the aircraft, which changes in different stages of flight.

Through simulation, they found that the morphing nose cone can reduce aerodynamic drag by more than 20 percent.

"The morphing structure provides an efficient way for aerospace vehicles to reduce aerodynamic drag and save fuel, which is of great importance to the commercial aerospace market," Hu said.

 

[JSCh]

PUBLIC RELEASE: 27-MAR-2018
What else can molecular perovskite do?
SCIENCE CHINA PRESS

A new molecular perovskite energetic material. ©Science China Press​

Molecular perovskites have attracted growing attentions for high-performance solar cells, photo-detectors, and ferroelectric materials. This sort of material is rather hot recently. "What else can molecular perovskite do, we have been thinking and exploring." introduced by Profs. Wei-Xiong Zhang and Xiao-Ming Chen, from Sun Yat-Sen University, China, whose group recently reported a new sort of high-energetic materials produced by inorganic-organic perovskites, published on Science China Materials, 2018, doi:10.1007/s40843-017-9219-9.

"As the simplest high-symmetry structure for ternary compounds, perovskite structure is very charming." said Prof. Zhang. Molecular perovskites topologically mimic the structure of inorganic perovskites, but have at least one molecular component. "We believe that, the diverse molecular components enable them to host many interesting phenomena and functionalities waiting to be discovered. Last year, we designed a molecular perovskite to host a new 'bond-switching' ferroelectric mechanism, and this time, we discovered that the molecular perovskites could be one sort of excellent energetic materials."

"Different from traditional strategy that the oxidizer and fuel groups are combined into a single molecule, we employed perovskite structure to incorporate the molecular oxidizer and fuel components into a ternary crystal for new energetic materials with high performance, high stability and low cost." said Prof. Zhang.

Since the black powder, the first known explosive, was discovered by ancient Chinese in the seventh century, people never stop finding more powerful, stable, reliable and low-cost energetic materials for military devices and civil industry.

Although their explosive performances are escalated with increasing the number of nitro-groups and the structural tension of carbon skeleton, the classic organic energetic compounds, such as trinitrotoluene (TNT), pentaerythritol tetranitrate (PETN), cyclotrimethylene trinitramine (RDX), cyclotetramethylene tetranitramine (HMX), hexanitrohexaazaisowurtzitane (CL-20) and octanitrocubane (ONC), generally become increasingly instable, sensitive and costly along with the generation.

"It is frustrated that the best practicable explosive is yet HMX, invented during the Second World War, despite its medium performance and cost." said Prof. Chen.

"The perovskite structure allows each fuel cation to be tightly surrounded by twelve oxidative anions and each oxidative anion surrounded by four fuel cations. Such compact and alternative arrangement of fuel and oxidizer components in a proper ratio is essential to achieve sufficient combustion in a very-short time and then a rapid detonation. In addition, we found that the perovskite structure leads to obvious structural tension in the cage whose size is almost not changed by alkaline metal ions with different size. It indicates that organic cations in the cage take steric effect on the anionic frameworks.", explained by Zhang.

Based on the calculation by professional software EXPLO5, the explosive performances, such as detonation heat, detonation velocity, detonation pressure, are improved.

"Beside the classical explanation that energy release is due to the breaking and recombination of chemical bonds during the denotation reaction, the release of the structural tension in the frameworks also make a great contribution to the explosive performances." emphasized by Zhang.

"The perovskite structure is favorable for the stability." added by Zhang, "The new explosive materials have rather high thermal stability and low impact sensitivity, which is good for their storage and transportation."

Strategically, Zhang highlighted "Different from traditional design focusing on the intra-molecular functional groups, we emphasize the inter-molecular assembly in the specified crystal." As he said, low-cost fuel and oxidizer are integrated into highly-symmetric ternary crystals. "This design is rather flexible. Molecular components with suitable shape and size can assemble into such kind of ternary crystals to optimize the oxygen balance, crystal density and so on. Better explosive performances are expected", said Zhang and Chen.

###​

This research was funded by the National Natural Science Foundation of China.

See the article: Chen Shao-Li, Yang Zi-Run, Wang Bin-Jie, Shang Yu, Sun Lin-Yin, He Chun-Ting, Zhou Hao-Long, Zhang Wei-Xiong*, Chen Xiao-Ming*. "Molecular perovskite high-energetic materials," Sci. China Mater. (2018), doi:10.1007/s40843-017-9219-9.

This article was published online http://engine.scichina.com/publisher/scp/journal/SCMs/doi/10.1007/s40843-017-9219-9?slug=full text
https://link.springer.com/article/10.1007/s40843-017-9219-9
​

What else can molecular perovskite do? | EurekAlert! Science News

 

[JSCh]

PUBLIC RELEASE: 28-MAR-2018
A paperlike LCD -- thin, flexible, tough and cheap
Less than half a millimeter thick, the new flexi-LCD design could revolutionize printed media.

AMERICAN INSTITUTE OF PHYSICS

This is a combined flexible blue optically rewritable LCD. CREDIT: Zhang et al.​

WASHINGTON, D.C., March 28, 2018 -- Optoelectronic engineers in China and Hong Kong have manufactured a special type of liquid crystal display (LCD) that is paper-thin, flexible, light and tough. With this, a daily newspaper could be uploaded onto a flexible paperlike display that could be updated as fast as the news cycles. It sounds like something from the future, but scientists estimate it will be cheap to produce, perhaps only costing $5 for a 5-inch screen. The new optically rewritable LCD design was reported this week in Applied Physics Letters, from AIP Publishing.

The team focused on two key innovations for achieving highly flexible designs. The first is the recent development of optically rewritable LCDs. Like conventional LCD displays, the display is structured like a sandwich, with a liquid crystal filling between two plates. Unlike conventional liquid crystals where electrical connections on the plates create the fields required to switch individual pixels from light to dark, optically rewritable LCDs coat the plates with special molecules that realign in the presence of polarized light and switch the pixels. This removes the need for traditional electrodes, reduces the structure's bulk and allows more choices in the type and thickness of plates. Consequently, optically rewritable LCDs are thinner than traditional LCDs, at less than half a millimeter thick, can be made from flexible plastic, and weigh only a few grams. "It's only a little thicker than paper," said Jiatong Sun, a co-author from Donghua University in China.

Optically rewritable LCDs are durable and cheap to manufacture because of their simple structure. Moreover, like an electronic paper screen in an e-book, energy is only required to switch display images or text. Therefore, running costs are low because these new LCDs don't need power to sustain an image once it is written on the screen.

The second innovation involves the spacers that create the separation of the plastic or glass plates. "We put spacers between glass layers to keep the liquid crystal layer uniform," Sun said. Spacers are used in all LCDs to determine the thickness of the liquid crystal. A constant thickness is necessary for good contrast ratio, response time and viewing angle. However, when plates bend, it forces the liquid crystal away from the impact site and leaves sections of the screen blank and so alterations in spacer design are critical to prevent liquid crystal in flexible LCDs from moving excessively. Developing a flexible design that overcomes this barrier has proven challenging.

The researchers tried three different spacer designs and found that a meshlike spacer prevented liquid crystal from flowing when their LCD was bent or hit. This innovation enabled them to create the first flexible optically rewritable LCD.

An additional innovation involved improved color rendering. The scientists report that until this study, optically rewritable LCDs had only been able to display two colors at a time. Now, their optically rewritable LCD simultaneously displays the three primary colors. They achieved this by placing a special type of liquid crystal behind the LCD, which reflected red, blue and green. To make this into a commercial product, Sun wants to improve the resolution of the flexible optically rewritable LCD.

"Now we have three colours but for full colour we need to make the pixels too small for human eyes to see," Sun said.



A paperlike LCD -- thin, flexible, tough and cheap | EurekAlert! Science News

Yihong Zhang, Jiatong Sun, Yang Liu, Jianhua Shang, Hao Liu, Huashan Liu, Xiaohui Gong, Vladimir Chigrinov, Hoi Sing Kowk. A flexible optically re-writable color liquid crystal display. Applied Physics Letters, 2018; 112 (13): 131902. DOI: 10.1063/1.5021619​

 

[JSCh]

X-ray ‘ghost images’ could cut radiation doses
By Sophia Chen
Mar. 28, 2018 , 1:00 PM

On its own, a single-pixel camera captures pictures that are pretty dull: squares that are completely black, completely white, or some shade of gray in between. All it does, after all, is detect brightness.

Yet by connecting a single-pixel camera to a patterned light source, a team of physicists in China has made detailed x-ray images using a statistical technique called ghost imaging, first pioneered 20 years ago in infrared and visible light. Researchers in the field say future versions of this system could take clear x-ray photographs with cheap cameras—no need for lenses and multipixel detectors—and less cancer-causing radiation than conventional techniques.

"Our system is much smaller and cheaper, and it could even be portable if you needed to take it into the field," says Wu Ling-An, a physicist at the Chinese Academy of Sciences in Beijing whose work with her colleagues was published on 28 March in Optica.

The researchers' system still isn't ready to be used in medicine. But they have lowered the x-ray dose by about a million times compared with earlier attempts, says Daniele Pelliccia, who in 2015 made some of the first x-ray ghost images. A physicist at Instruments & Data Tools, an optics startup near Melbourne, Australia, he used a building-size source of intense x-rays called a synchrotron, but Wu's group made do with a compact tabletop source. And whereas early x-ray ghost images were simple pictures of slits cut into metal, the Chinese group produced outlines of a seashell and of initials etched into metal plates. They have made "images that look like images," Pelliccia says. "The potential payback, if it works for medical images, is big."

The key to ghost imaging is to illuminate an object with light that has passed through a filter with a known pattern, says Miles Padgett, a physicist at the University of Glasgow in the United Kingdom. On the other side of the object, the single-pixel camera takes a picture—nothing more than a gray square. To end up with an image, you do this thousands of times, swapping out the filter pattern for a different one after each exposure. Wu's group used a piece of sandpaper, which is partially transparent to x-rays, and rotated it to create a different pattern after each exposure.

Seeing ghosts
Using a patterned light filter and a single-pixel detector, researchers can make crisp pictures of objects, even though the detector only captures unresolved, gray squares.

A computer produces the final image. Because the computer knows the filter pattern for each exposure, it can calculate the image from variations in the sequence of gray pixels captured by the camera. The result, in theory, is an x-ray image as good as any today, but without a high-resolution camera or the intense x-rays needed for conventional imaging.

Researchers have already demonstrated simple ghost imaging systems for optical and infrared light, which rely on programmable filters, says Jeffrey Shapiro, a physicist at the Massachusetts Institute of Technology in Cambridge. A computer records and resets the filter pattern as the light source projects it onto the object and the single-pixel detector.

Using an infrared system, Padgett's group has shown it can ghost-image a methane gas leak. The group's industry collaborator, M Squared Lasers, based in Glasgow, is working to commercialize the system and hoping to sell detectors to the oil and gas industry as a cheaper way to detect leaky pipelines, Padgett says.

Making a computer-programmable filter for x-rays is a bigger challenge, Wu says, because x-rays simply stream through most materials. Because her group resorted to unprogrammable sandpaper, it had to use a high-resolution camera to measure the patterns. But you could imagine a commercial x-ray system in which the manufacturer prerecords all the sandpaper patterns, Padgett says. Then, only the manufacturer would need the high-resolution camera, and individual users could simply buy a single-pixel camera and use the sandpaper filters in a specified sequence.

In order for ghost imaging to be viable in medicine, Wu says, researchers must show that the total x-ray dose needed for an image is lower than with a conventional system. One ghost image requires thousands of exposures, and the x-rays add up. In addition, the more detailed the object—for example, a human body—the more exposures you need. However, Wu says the x-ray intensity per exposure can be made low enough that ghost imaging may come out ahead.

Doing so would be important, Shapiro says. "If you could reduce the amount of x-ray exposure that women suffer in getting mammograms, or in chest exams, that would be a big deal," he says. But image quality still needs to be improved, he says. "It's got to be a good image."

doi:10.1126/science.aat7285


X-ray ‘ghost images’ could cut radiation doses | Science | AAAS

 

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Chinese scientists create pig model of Huntington's disease
Source: Xinhua 2018-03-30 02:10:20

WASHINGTON, March 29 (Xinhua) -- A Chinese team of scientists has established a pig model of Huntington's disease (HD), an inherited neurodegenerative disease, using genetic engineering technology.

In a study published in Cell on Thursday, researchers anticipated that the pigs could be a practical way to test treatments for HD, which is caused by a gene encoding a toxic protein that causes brain cells to die.

Although genetically modified mice have been used widely to model neurodegenerative diseases, they lack the typical neurodegeneration or overt neuronal loss seen in human brains, according to corresponding author Li Xiaojiang, professor of human genetics in Jinan University and who runs a lab at Emory University School of Medicine.

The pig HD model is an example that suggests large animal models could better model other neurodegenerative diseases, such as Alzheimer's and Parkinson's.

A HD pig could be an opportunity to test if the CRISPR-Cas9 gene editing technique can work in larger animals before clinical applications in humans.

Li said, in comparison with mice, treatments for affected nervous system tissues could be better tested in pigs, because their size is closer to that of humans. The pig model of HD also more closely matches the symptoms of the human disease.

Compared with non-human primate models, the pigs offer advantages of faster breeding and larger litter sizes, the researchers said.

Li collaborated with his colleagues at Jinan University and Chinese Academy of Sciences in Guangzhou. The pigs are now housed in Guangzhou.

"In pigs, the pattern of neurodegeneration is almost the same as in humans, and there have been several treatments tested in mouse models that didn't translate to human," said a co-senior author Li Shihua, professor of human genetics at Emory University School of Medicine.

Symptoms displayed by the genetically altered pigs include movement problems. They show respiratory difficulties, which resemble those experienced by humans with HD and are not seen in mouse models of HD.

In addition, the pigs show degeneration of the striatum, the region of the brain most affected by HD in humans, more than other regions of the brain.

Huntington's disease is caused by a gene encoding a toxic protein (mutant huntingtin or mHTT), and mHTT contains abnormally long repeats of a single amino acid, glutamine. Symptoms commonly appear in mid-life and include uncontrolled movements, mood swings and cognitive decline.

Researchers used the CRISPR/Cas9 gene editing technique to introduce a segment of a human gene causing Huntington's, with a very long glutamine repeat region, into pig fibroblast cells.

Then somatic cell nuclear transfer generated pig embryos carrying this genetic alteration. The alteration is referred to a "knock in" because the changed gene is in its natural context.

Sen Yan, Zhuchi Tu, Zhaoming Liu, Nana Fan, Huiming Yang, Su Yang, Weili Yang, Yu Zhao, Zhen Ouyang, Chengdan Lai, Huaqiang Yang, Li Li, Qishuai Liu, Hui Shi, Guangqing Xu, Heng Zhao, Hongjiang Wei, Zhong Pei, Shihua Li, Liangxue Lai, Xiao-Jiang Li. A Huntingtin Knockin Pig Model Recapitulates Features of Selective Neurodegeneration in Huntington’s Disease. Cell, 2018; DOI: 10.1016/j.cell.2018.03.005
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[JSCh]

How China is using military radar technology to wage war on mosquitoes
Scientists are developing a device to detect the insect flapping its wings up to 2km away – and it could be used to save millions of lives, researcher says

PUBLISHED : Friday, 30 March, 2018, 10:27am
UPDATED : Friday, 30 March, 2018, 11:10am

Stephen Chen

China is developing a super-sensitive radar that can detect the wing-flapping of a mosquito up to 2 kilometres away, according to a senior scientist involved in the government research project.

A prototype of the device is being tested at a defence laboratory at the Beijing Institute of Technology (BIT), said the researcher, who declined to be named as the project involves sensitive technology used in China’s missile defence system.

“Identifying and tracking individual, mosquito-sized targets is no longer science fiction,” he said. “We are actually quite close to bringing this technology out of the laboratory and using it to save lives.”

Mosquitoes have claimed more human lives than all wars combined – their infectious bites still cause more than one million deaths each year, according to the World Health Organisation.

The insect plays host to a wide range of disease-bearing microorganisms, from malaria to newer viruses such as Zika.

China powers up new radar tech to unmask stealth fighters

Controlling the pest is a major challenge, though, as they can come and go almost without a trace – their familiar buzzing is a giveaway, but only when they are close by.

After decades of development, modern military radars can now pick up the echoes of small objects at an impressive distance. The US Missile Defence Agency’s sea-based X-band radar, for example, can detect a baseball-sized object from about 4,000km (2,500 miles) away.

China has developed radar systems with similarly advanced features to track missiles and stealth aircraft, but some scientists working on these military projects believed the technology could also be used to fight mosquitoes – and they convinced the government to fund their research.

The team, led by Long Teng, received funding of more than 82 million yuan (US$12.9 million) from the central government at the end of last year to build a full-sized mosquito detection radar that could be tested in the field.

Long is director of BIT’s Radar Technology Research Institute and a lead scientist on China’s key military radar programme, according to the university’s website. He could not be reached for comment.

How to wipe out mosquitoes and eradicate malaria? A mutant fungus may hold the answer

The radar works by emitting rapid pulses of electromagnetic waves that travel at many frequencies, according to the scientist working on the project. When the radio waves hit a mosquito they bounce back with information including species, gender, flying speed and direction, and whether the insect has eaten.

It could be mounted on a rooftop overlooking a residential community and used to pinpoint the position of major mosquito colonies, their breeding and resting areas. And if a colony was migrating to another neighbourhood, households in its way could be warned.

Scientists in other countries have used civilian radar networks to track the group movement of birds or larger insects such as locusts and moths, but this is believed to be the first attempt to use radars to monitor mosquitoes.

The researcher said the prototype had achieved unprecedented sensitivity because the authorities had allowed the team to build the system using the latest military radar technology.

It has, for example, an advanced phased array antenna similar to those used on China’s latest warships. The antenna can beam microwaves in different directions at the same time and can detect missiles or military jets much faster than conventional radars that use a rotating dish.

It also has a separate antenna to generate radio waves oscillating in more than one direction. Known as polarisation, this provides detailed information about a target so that the researchers can distinguish a hungry, blood-sucking female mosquito from a pollen-eating male.

A fast computer then uses an algorithm to simultaneously identify and follow the movement of many mosquitoes in the same community.

China builds ‘world’s biggest air purifier’ (and it seems to be working)

The project is a collaboration between insect behaviourists and scientists from many other disciplines, according to the researcher. By providing a vast amount of data, the radar has the potential to help biologists learn more about the individual and collective behaviour of the pest, which could lead to new strategies to fight the spread of mosquito-borne diseases.

The researcher added that the team had made progress on the existing technology and it could also have military applications, without elaborating. He also declined to say when the first full-sized radar would be completed.

“We are building one or two units at the moment. In the future we hope the radar will be made in large numbers and installed across the country to form a large network to monitor the movements of airborne animals [as well as mosquitoes],” he said.

​

Yi Zhenyuan, an award-winning military radar researcher and deputy director of the electrical engineering department at Harbin Institute of Technology, said identifying and tracking such a minuscule target from kilometres away was extremely difficult.

Existing military radar technology could detect small, uncooperative signals from hundreds to thousands of kilometres away, but mosquitoes were “another story”, he said.

Yi, who has knowledge of the radar but is not involved in the project, said mosquitoes would be more difficult to detect than a stealth aircraft like the F-22, which has a special coating and geometric design to avoid showing up on radar screens.

“Mosquito wings of course are a lot different from the metal wings of a military jet, and so are their structures, shapes and movements. The mosquito radar is going to need a completely new set of algorithms,” he said.

Mosquitoes also fly at low speed, sometimes just hovering in the air, which makes some of the military radar technology designed to detect fast-moving targets less useful to the project.

The biggest challenge will come from the environment, Yi said, since the radio waves from a mosquito were extremely weak and could easily be overwhelmed by background noise.

“So what works perfectly well in a laboratory may not be so successful out in the field,” he said.

Hong Kong citizen scientists localise mosquito tracking app to let people report sightings of the disease carriers

Liu Xingyue, a professor of insect studies at the China Agricultural University in Beijing, said the radar programme could allow pest controllers to closely monitor mosquito and other small insect populations in an area.

He said regions including the northeast of China, tropical countries and Africa were still troubled by mosquitoes and the diseases they carried.

Behavioural differences such as wing flapping could be picked up by the radar, giving scientists a “precision-guided weapon in our war against the deadliest creature on Earth”, he said. “Millions of lives could be saved.”


How China is using military radar technology to wage war on mosquitoes | South China Morning Post

 

[JSCh]

Anti-aging protein alpha Klotho's molecular structure revealed
March 29, 2018
UT Southwestern Medical Center

Researchers from UT Southwestern's Charles and Jane Pak Center for Mineral Metabolism and Clinical Research and Internal Medicine's Division of Nephrology recently published work in Nature that reveals the molecular structure of the so-called "anti-aging" protein alpha Klotho (a-Klotho) and how it transmits a hormonal signal that controls a variety of biologic processes. The investigation was performed in collaboration with scientists from New York University School of Medicine and Wenzhou Medical University in China.

Studies at UTSW two decades ago by Dr. Makoto Kuro-o, Professor of Pathology, demonstrated that mice lacking either a-Klotho or the hormone FGF23 suffered from premature and multiple organ failure as well as other conditions, including early onset cardiovascular disease, cancer, and cognitive decline. Because defects in a-Klotho lead to symptoms seen in aging, researchers inferred that a-Klotho suppresses aging, leading to great interest in how the a-Klotho protein might work together with the hormone FGF23 to fulfill their roles.

a-Klotho can exist on the surface of a cell or can be released from the cell and circulate in body fluids, including the blood, as soluble a-Klotho. The cell-attached form and the circulating form of a-Klotho were previously and universally believed to serve completely different functions.

"The a-Klotho gene [then called Klotho] was cloned by Dr. Kuro-o in 1997 shortly before he was recruited here, and during his tenure at UT Southwestern he has carried out the most seminal work in this field," said Pak Center Director Dr. Orson Moe. "The gene protects against many diseases, including cardiovascular disease, cancer, diabetes, aging, neurodegeneration, and kidney disease. The structure of the a-Klotho protein and how the protein functions, however, largely remained a mystery until this current work."

By providing a first look at the structure of the protein complex that includes FGF23 and its co-receptors, the FGF receptor and a-Klotho, the most recent study challenges the long-accepted belief that only the cell-attached form of aKlotho can serve as a receptor for FGF23 and hence that FGF23 action is restricted to tissues having the cell-attached form.

Study authors include Dr. Moe, Professor of Internal Medicine and Physiology, and Dr. Ming Chang Hu, Associate Professor of Internal Medicine and Pediatrics. Dr. Moe holds The Charles Pak Distinguished Chair in Mineral Metabolism, and the Donald W. Seldin Professorship in Clinical Investigation. Dr. Hu holds the Makoto Kuro-o Professorship in Bone and Kidney Research.

One of the major, paradigm-changing findings revealed by solving the protein complex structure is that the circulating form of soluble a-Klotho can actually serve as a co-receptor for FGF23. Thus, the soluble form of a-Klotho can go to any cell in the body and act as a co-receptor for FGF23, rendering every cell a possible target of FGF23, representing a major paradigm shift.

"a-Klotho researchers in cancer, aging, neurologic, cardiovascular, and kidney disease will benefit from this research," Dr. Moe said. "The knowledge of the structure of the protein, along with its molecular binding partners, will enable us to greatly advance the understanding of how a-Klotho works and also how to best design therapeutic strategies and novel agents that can either activate or block FGF23-a-Klotho interaction and signaling as needed."

Collaboratively led by NYU School of Medicine structural biologist Dr. Moosa Mohammadi, the investigation included researchers from UTSW, the Rockefeller University-based New York Structural Biology Center, and Wenzhou Medical University.

The study provides evidence for how FGF23 signals to cells by forming a complex with a-Klotho and the two other molecular partners. Made by bone cells, the FGF23 hormone travels via the bloodstream to cells in all organs, where it regulates many aspects of mineral metabolism. Abnormal FGF23 levels are found in many disease states. In chronic kidney disease, for example, high FGF23 levels are believed to cause many of the disease's complications and fatalities.

The researchers say their findings also shed new light on how kidney disease leads to an abnormal thickening of heart muscle tissue called hypertrophy, which is a leading cause of death in people with kidney disease caused by high blood pressure, diabetes, and other illnesses. When damaged kidney tubules can no longer eliminate phosphate in the urine, FGF23 rises, initially as an effort to keep blood phosphate in check. With time, FGF23 can rise to harmful levels.

A prevailing hypothesis has been that very high levels of FGF23 cause hypertrophy in the heart. But the theory remained controversial because heart tissue does not have a-Klotho, which must be present if FGF23 is to signal. The latest findings indicate that a-Klotho can be "delivered" through the bloodstream to organs where it is not normally present. This could potentially launch drug development programs for kidney disease, the researchers said.

"The solution of this protein structure will guide many future studies," Dr. Moe said. "There are numerous diseases that involve a-Klotho deficiency. Replenishment of a-Klotho by either recombinant protein injection or drugs that increase a patient's own a-Klotho will have potential therapeutic implications for neurologic, metabolic, cardiovascular and kidney disease, and cancer."

Story Source:

Materials provided by UT Southwestern Medical Center. Note: Content may be edited for style and length.

Journal Reference:

1. Gaozhi Chen, Yang Liu, Regina Goetz, Lili Fu, Seetharaman Jayaraman, Ming-Chang Hu, Orson W. Moe, Guang Liang, Xiaokun Li, Moosa Mohammadi. α-Klotho is a non-enzymatic molecular scaffold for FGF23 hormone signalling. Nature, 2018; 553 (7689): 461 DOI: 10.1038/nature25451

Anti-aging protein alpha Klotho's molecular structure revealed -- ScienceDaily

 

[JSCh]

Live heart cells make this material shift color like a chameleon
The hydrogel-based strips change hues when contracting and expanding

BY MARIA TEMMING
2:00PM, MARCH 28, 2018

KEEPING THE BEAT Five hydrogel strips covered in heart tissue contract when the heart cells do. That shrinkage makes the material reflect more blue light. When the cells relax, the strips extend and reflect more red light.
F. FU ET AL/SCIENCE ROBOTICS 2018

To craft a new color-switching material, scientists have again taken inspiration from one of nature’s masters of disguise: the chameleon.

Thin films made of heart cells and hydrogel change hues when the films shrink or stretch, much like chameleon skin. This material, described online March 28 in Science Robotics, could be used to test new medications or possibly to build camouflaging robots.

The material is made of a paper-thin hydrogel sheet engraved with nanocrystal patterns, topped with a layer of living heart muscle cells from rats. These cells contract and expand — just as they would inside an actual rat heart to make it beat — causing the underlying hydrogel to shrink and stretch too. That movement changes the way light bounces off the etched crystal, making the material reflect more blue light when it contracts and more red light when it’s relaxed.

This design is modeled after nanocrystals embedded in chameleon skin, which also reflect different colors of light when stretched (SN Online: 3/13/15).

When researchers treated the material with a drug normally used to boost heart rate, the films changed color more quickly — indicating the heart cells were pulsating more rapidly. That finding suggests the material could help drug developers monitor how heart cells react to new medications, says study coauthor Luoran Shang, a physicist at Southeast University in Nanjing, China. Or these kinds of films could also be used to make color-changing skins for soft robots, Shang says.

Citations
F. Fu et al. Bioinspired living structural color hydrogels. Science Robotics. Published online March 28, 2018. doi: 10.1126/scirobotics.aat3911.
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Live heart cells make this material shift color like a chameleon | Science News

 

[JSCh]

Chinese researchers develop new fire-resistant construction material
Source: Xinhua| 2018-04-03 13:20:39|Editor: Mengjie


HEFEI, April 3 (Xinhua) -- Researchers from the University of Science and Technology of China have developed a new fire-retardant construction material that can resist about 1,300 degrees Celsius flame without disintegration.

A research team led by Prof. Yu Shuhong have come up with a composite aerogel with low thermal conductivity and excellent fire resistance.

The composite, synthesized from phenol-formaldehyde-resin and silica, can resist a high-temperature flame without disintegration, said researcher Yu Zhilong.

The composite is highly porous and resilient. It displays better fire-resistance than current insulation materials such as expanded polystyrene and glass wool.

According to researchers, if used in walls, the material could provide extended protection against fire-induced collapse of reinforced concrete structures, winning more time for evacuation of the building.

It can also be used to insulate older buildings.

The research results were published in Angewandte Chemie, a German academic journal.

 

[JSCh]

China to strengthen security, management of scientific data
2018-04-03 10:52 GMT+8

China will strengthen and standardize the management of scientific data to guarantee data security and enhance data sharing, according to measures issued by the General Office of the State Council.

The measures are expected to provide better support to national scientific and technological innovation, economic and social development, as well as state security.

China has seen a scientific data boom in both quantity and quality, with growing input in science and technology research in recent years.

The data have not only impacted many scientific fields, such as bioscience, astronomy, geoscience and physics, but have also triggered important revolutions in research methods.

China has seen a scientific data boom in both quantity and quality, with growing input in science and technology research in recent years. /VCG Photo

Scientific and technological innovation has become more dependent on large, reliable sets of scientific data. China still has a lot to do in developing, utilizing, opening, sharing and protecting data.

The measures, which prioritize data security and focus on data sharing, require those who own the data to be responsible for data management.

The measures also ordered strengthening supervision of the use and sharing of scientific data.

The data users and producers must act in line with related standards to improve protection of intellectual property, according to the measures.

The data generated from scientific programs must be collected and reported, so that they can be managed in a standard fashion and stored long-term in data centers, according to the measures.

(Cover: VCG Photo)

 

[JSCh]

Progeny of world's first cloned cashmere goat born in China
Source: Xinhua| 2018-04-03 16:11:13|Editor: Lifang


HOHHOT, April 3 (Xinhua) -- Two kids have been born in north China's Inner Mongolia Autonomous Region, the offspring of the world's first cloned cashmere goat, the Bayannur city government said Tuesday.

The two kids, born on Wednesday and Thursday respectively after a natural reproduction process, are strong and in good conditions, according to researchers.

"The successful breeding will accelerate the application of clone technology in cashmere goat husbandry," said a researcher at the animal breeding base where the kids were born.

The father, the world's first cloned cashmere goat, was born in December 2016. To test its breeding capabilities, researchers let it mate with more than 20 female goats and most were impregnated.

The superfine cashmere fiber from the goat is less than 13.8 micrometers thick, much finer than the average of 15.8 micrometers on the famous Erlang Mountain goats in Inner Mongolia.

 

[JSCh]

PUBLIC RELEASE: 3-APR-2018
Researchers develop nanoparticle films for high-density data storage
New holographic data storage medium could enable wearable technology that captures and stores detailed 3-D images

THE OPTICAL SOCIETY

Researchers created a nanofilm that can store data holographically and is environmentally stable. Here, Shencheng Fu carries out experiments with the new film. CREDIT: Northeast Normal University

WASHINGTON -- As we generate more and more data, the need for high-density data storage that remains stable over time is becoming critical. New nanoparticle-based films that are more than 80 times thinner than a human hair may help to fill this need by providing materials that can holographically archive more than 1000 times more data than a DVD in a 10-by-10-centimeter piece of film. The new technology could one day enable tiny wearable devices that capture and store 3-D images of objects or people.

"In the future, these new films could be incorporated into a tiny storage chip that records 3-D color information that could later be viewed as a 3-D hologram with realistic detail," said Shencheng Fu, who led researchers from Northeast Normal University in China who developed the new films. "Because the storage medium is environmentally stable, the device could be used outside or even brought into the harsh radiation conditions of outer space."

In the journal Optical Materials Express, the researchers detail their fabrication of the new films and demonstrate the technology's ability to be used for an environmentally-stable holographic storage system. The films not only hold large amounts of data, but that data can also be retrieved at speeds up to 1 GB per second, which is about twenty times the reading speed of today's flash memory.

Storing more data in less space

The new films are designed for holographic data storage, a technique that uses lasers to create and read a 3-D holographic recreation of data in a material. Because it can record and read millions of bits at once, holographic data storage is much faster than optical and magnetic approaches typically used for data storage today, which record and read individual bits one at a time. Holographic approaches are also inherently high-density because they record information throughout the 3-D volume of the material, not just on the surface, and can record multiple images in the same area using light at different angles or consisting of different colors.

Recently, researchers have been experimenting with using metal-semiconductor nanocomposites as a medium for storing nanoscale holograms with high spatial resolution. Porous films made of the semiconductor titania and silver nanoparticles are promising for this application because they change color when exposed to various wavelengths, or colors, of laser light and because a set of 3-D images can be recorded at the focus area of laser beam using a single step. Although the films could be used for multiwavelength holographic data storage, exposure to UV light has been shown to erase the data, making the films unstable for long-term information storage.

Recording a holographic image into titania-silver films involves using a laser to convert the silver particles into silver cations, which have a positive charge due to extra electrons. "We noticed that UV light could erase the data because it caused electrons to transfer from the semiconductor film to the metal nanoparticles, inducing the same photo transformation as the laser," said Fu. "Introducing electron-accepting molecules into the system causes some of the electrons to flow from the semiconductor to these molecules, weakening the ability of UV light to erase the data and creating an environmentally stable high-density data storage medium."

Changing the electron flow

For the new films, the researchers used electron-accepting molecules that measured only 1 to 2 nanometers to disrupt the electron flow from the semiconductor to the metal nanoparticles. They fabricated semiconductor films with a honeycomb nanopore structure that allowed the nanoparticles, electron-accepting molecules and the semiconductor to all interface with each other. The ultrasmall size of the electron-accepting molecules allowed them to attach inside the pores without affecting the pore structure. The final films were just 620 nanometers thick.

The researchers tested their new films and found that holograms can be written into them efficiently and with high stability even in the presence of UV light. The researchers also demonstrated that using the electron-acceptors to change the electron flow formed multiple electron transferring paths, making the material respond faster to the laser light and greatly accelerating the speed of data writing.

"Particles made from noble metals such as silver are typically viewed as a slow-response media for optical storage," said Fu. "We show that using a new electron transport flow improves the optical response speed of the particles while still maintaining the particle's other advantages for information storage."

The researchers plan to test the environmental stability of the new films by performing outdoor tests. They also point out that real-life application of the films would require the development of high efficiency 3-D image reconstruction techniques and methods for color presentation for displaying or reading the stored data.

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Paper: S. Liu, S. Fu, X. Zhang, X. Wang, L. Kang, X. Han, X. Chen, J. Wu, Y. Liu, "UV-resistant holographic data storage in noble-metal/semiconductor nanocomposite films with electron-acceptors," Opt. Mater. Express Volume 8, Issue 5, 1143-1153 (2018). DOI: 10.1364/OME.8.001143.



Researchers develop nanoparticle films for high-density data storage | EurekAlert! Science News