China Science & Technology Forum

[JSCh]

Could these crystals be the next leap forward in China’s laser technology? | South China Morning Post

• Researchers say they have developed a substance that is 13 times better in tests than widely used alternative
• Experiments could help solve a power source problem that has plagued commercial and military devices

Stephen Chen
Published: 3:29pm, 4 Sep, 2019

Scientists at the Fujian Institute of Research on the Structure of Matter think they have found a super efficient crystal to make high-energy beams from low-energy lasers. Photo: Alamy

Scientists in southeast China say they have synthesised a crystal with the potential to significantly improve the performance of lasers used in consumer and military equipment.

Crystals of caesium bismuth germanate (CBGO) can turn low-energy beams into high-energy emissions with unparalleled efficiency, according to Professor Mao Jianggao, team leader at the Fujian Institute of Research on the Structure of Matter, part of the Chinese Academy of Sciences, in Fuzhou.

The team looked at several candidate crystals in their experiments. Compared with widely used potassium dihydrogen phosphate crystals, the CBGO crystal was 13 times more efficient at turning infrared lasers into more energised green beams.

“This is a record performance,” Mao said on Tuesday. “This is why we think the crystal may have potential.”

China’s prototype Guanlan anti-submarine warfare satellite uses a high-energy laser to sweep beneath the sea to a depth of 500 metres. Illustration: SCMP

Their findings were published in the German weekly scientific peer-reviewed journal Angewandte Chemie, or Applied Chemistry, last month.

The researchers said CBGO crystals could be a way around a problem that has limited the performance of lasers – the huge amount of electricity needed to power them.

The demand on power is great because existing technology is not efficient at converting low-energy beams to high-energy ones – one reason that laser weapons are not yet as common as scientists predicted in the 1960s.

CBGO belongs to a family known as non-linear crystals, which cause abrupt changes to energy that passes through them. The scientists found that CBGO crystals could double the frequency of a laser beam.

As high-energy lasers can be created by merging two low-energy photons, or particles of light, a process known as frequency doubling, CBGO crystals are an ideal medium, and the higher frequency of the laser, the more energy it carries.

Many military and civilian applications required high-energy beams, they said. These included directed energy weapons designed to destroy drones or missiles, or China’s prototype Guanlan anti-submarine warfare satellite, which will use a green laser to penetrate water to a depth of 500 metres (1,640 feet) to detect a target.

Mao said his team’s research was at an early stage and that years of testing would be needed before the CBGO crystals found their way to market.

The CBGO crystal grown in the Fuzhou laboratory was the size of a grain of sand, he said. For industrial use, crystals would need to be at least the size of a dice.

Growing them was a very slow and challenging job, and there was no certainty that CBGO crystals could be grown on an industrial scale, Mao said.

China is a world leader in crystal research, and some of those most commonly used in laser devices were developed by Chinese scientists thanks to heavy investment from central government.

Professor Li Qiang, deputy director with the Institute of Laser Engineering at Beijing University of Technology, said the discovery of CBGO was encouraging, but its success should be evaluated not only on its efficiency, but also on attributes such as mechanical strength, tolerance to laser damage, and stability in extreme environments such as high humidity.

“Lots of crystals have been proposed over the decades, but only a handful are useful. It’s a high-risk business,” Li said. “China has achieved a leading position in this field not because of luck, but by continuous effort by several generations of researchers through countless failures.”

 

[JSCh]

NEWS * 04 SEPTEMBER 2019
Ancient worm fossil rolls back origins of animal life
Half-a-billion-year-old creature challenges theory that animals burst onto the scene in an abrupt event known as the Cambrian explosion.

Colin Barras

A fossil of Yilingia spiciformis and the track it left as it moved.Credit: Z. Chen et al./Nature

More than half a billion years ago, a strange, worm-like creature died as it crawled across the muddy sea floor. Both the organism and the trail it left lay undisturbed for so long that they fossilized. Now, they are helping to revise our understanding of when and how animals evolved.

The fossil, which formed some time between 551 million and 539 million years ago, in the Ediacaran period, joins a growing body of evidence that challenges the idea that animal life on Earth burst onto the scene in an event known as the Cambrian explosion, which began about 539 million years ago.

“It is just pushing things further and further back into the Ediacaran,” says Rachel Wood, a geoscientist at the University of Edinburgh, UK. The Cambrian explosion no longer appears to be such an abrupt event in the history of life on Earth, she says. An analysis of the fossil, along with a few dozen similar specimens found in the same rock sequence in southern China, is published in Nature1.

“What’s extraordinary about this paper is it’s three home runs in the same five-page manuscript,” says Simon Darroch, a palaeontologist at Vanderbilt University in Nashville, Tennessee. First, it’s exceptionally rare to find a dead animal preserved at the end of a trail it made when alive, he says. Second, the fossil dates to a crucial moment in the evolution of animal life.

And third: “It’s such a bizarre-looking organism,” says Darroch. The creature, which has been named Yilingia spiciformis and was up to 27 centimetres long, seems to be a biologically complex animal with a distinct front and rear end. “We don’t really have many of those from the Ediacaran,” he says.

Ancient organisms
The rock record has already revealed that the Ediacaran seas were rich in life, but many Ediacaran fossils have strange anatomical features that are unlike those seen in modern animals. Because of this, palaeontologists have struggled to relate the Ediacaran organisms to the creatures of the Cambrian period. This bolstered the idea that the Cambrian explosion represented the dramatic first appearance of familiar animals.

But opinions have begun to shift in the past few years. Some Ediacaran organisms have been recognized as animals despite their peculiar anatomy, which suggests that animal life began millions of years before the Cambrian explosion.

Yilingia spiciformis fits into that picture and pushes the idea further. With a segmented body that is symmetrical down its length, it has an anatomy that is more obviously similar to that of Cambrian animals, says Shuhai Xiao, a palaeontologist at Virginia Tech in Blacksburg and a co-author of the study.

Like modern animals, Y. spiciformis had a distinct front and back end: the fossil tapers towards the rear.Credit: Z. Chen et al./Nature

What’s more, the trail demonstrates that Y. spiciformis could crawl over the sea floor like a modern animal. Palaeontologists have found only few pieces of evidence that the strange organisms of the Ediacaran were similarly mobile. Collectively, Xiao’s team’s findings mean that Y. spiciformis looked and behaved like a Cambrian animal — despite living up to 12 million years before what is usually considered the start of the Cambrian explosion.

“In the past, palaeontologists emphasized the differences between the Ediacaran and Cambrian,” says Xiao. “But when you think about it, life had to continue through the boundary. Some lineages had to survive.”

Seeking descendants
Exactly which animal lineage Y. spiciformis belonged to is unclear. The researchers suggest it might be a relative of insects and crustaceans such as shrimp and lobsters, because it seems to have leg-like structures. If further analysis shows that those structures are actually an artefact of the fossilization process, the animal might instead be some sort of primitive segmented worm.

“There’s a third possibility,” says Xiao: it could be an ancestor to both groups. The idea that segmented worms and shrimp-like creatures all evolved from a single group of segmented animals dates back to the nineteenth century, but it’s controversial because most researchers now think that shrimp-like animals are more closely related to nematode worms and other creatures that grow by shedding an exoskeleton.

Xiao thinks the evolution of segments could have been a key event in the history of animal life. Segmented animals might be able to evolve more or fewer segments without fatally disrupting their biology. So, he reasons, once a single group of segmented animals evolved, it might have had great potential to diversify into a whole range of lineages adapted to new niches, explaining why animal life flourished a few million years after Y. spiciformis appeared.

But Doug Erwin, a palaeobiologist at the Smithsonian National Museum of Natural History in Washington DC, isn’t convinced by the idea: he thinks segmentation probably arose several times in animal evolution. Partly as a consequence, he thinks Y. spiciformis could even belong to a completely different branch of the animal evolutionary tree, which has since gone extinct.


Ancient worm fossil rolls back origins of animal life | Nature

Zhe Chen, Chuanming Zhou, Xunlai Yuan, Shuhai Xiao. Death march of a segmented and trilobate bilaterian elucidates early animal evolution. Nature (2019); DOI: 10.1038/s41586-019-1522-7​

 

[055_destroyer]

Could these crystals be the next leap forward in China’s laser technology? | South China Morning Post

• Researchers say they have developed a substance that is 13 times better in tests than widely used alternative
• Experiments could help solve a power source problem that has plagued commercial and military devices

Stephen Chen
Published: 3:29pm, 4 Sep, 2019

Scientists at the Fujian Institute of Research on the Structure of Matter think they have found a super efficient crystal to make high-energy beams from low-energy lasers. Photo: Alamy

Scientists in southeast China say they have synthesised a crystal with the potential to significantly improve the performance of lasers used in consumer and military equipment.

Crystals of caesium bismuth germanate (CBGO) can turn low-energy beams into high-energy emissions with unparalleled efficiency, according to Professor Mao Jianggao, team leader at the Fujian Institute of Research on the Structure of Matter, part of the Chinese Academy of Sciences, in Fuzhou.

The team looked at several candidate crystals in their experiments. Compared with widely used potassium dihydrogen phosphate crystals, the CBGO crystal was 13 times more efficient at turning infrared lasers into more energised green beams.

“This is a record performance,” Mao said on Tuesday. “This is why we think the crystal may have potential.”

China’s prototype Guanlan anti-submarine warfare satellite uses a high-energy laser to sweep beneath the sea to a depth of 500 metres. Illustration: SCMP

Their findings were published in the German weekly scientific peer-reviewed journal Angewandte Chemie, or Applied Chemistry, last month.

The researchers said CBGO crystals could be a way around a problem that has limited the performance of lasers – the huge amount of electricity needed to power them.

The demand on power is great because existing technology is not efficient at converting low-energy beams to high-energy ones – one reason that laser weapons are not yet as common as scientists predicted in the 1960s.

CBGO belongs to a family known as non-linear crystals, which cause abrupt changes to energy that passes through them. The scientists found that CBGO crystals could double the frequency of a laser beam.

As high-energy lasers can be created by merging two low-energy photons, or particles of light, a process known as frequency doubling, CBGO crystals are an ideal medium, and the higher frequency of the laser, the more energy it carries.

Many military and civilian applications required high-energy beams, they said. These included directed energy weapons designed to destroy drones or missiles, or China’s prototype Guanlan anti-submarine warfare satellite, which will use a green laser to penetrate water to a depth of 500 metres (1,640 feet) to detect a target.

Mao said his team’s research was at an early stage and that years of testing would be needed before the CBGO crystals found their way to market.

The CBGO crystal grown in the Fuzhou laboratory was the size of a grain of sand, he said. For industrial use, crystals would need to be at least the size of a dice.

Growing them was a very slow and challenging job, and there was no certainty that CBGO crystals could be grown on an industrial scale, Mao said.

China is a world leader in crystal research, and some of those most commonly used in laser devices were developed by Chinese scientists thanks to heavy investment from central government.

Professor Li Qiang, deputy director with the Institute of Laser Engineering at Beijing University of Technology, said the discovery of CBGO was encouraging, but its success should be evaluated not only on its efficiency, but also on attributes such as mechanical strength, tolerance to laser damage, and stability in extreme environments such as high humidity.

“Lots of crystals have been proposed over the decades, but only a handful are useful. It’s a high-risk business,” Li said. “China has achieved a leading position in this field not because of luck, but by continuous effort by several generations of researchers through countless failures.”

Future laser gun is not far off.

 

[JSCh]

NEWS AND VIEWS * 04 SEPTEMBER 2019
A key to unlocking chromatin revealed by complex structures
Histone proteins pack DNA into a condensed form called chromatin. Detailed structures of the MLL family of histone-modifying protein complexes have been defined, shedding light on how they operate.

Steven J. Gamblin & Jon R. Wilson

Each human cell contains so much DNA — about 2 metres if extended — that it must be tightly wrapped around specialized histone proteins to form spool-like structures called nucleosomes. Nucleosomes can then be packed together into dense strands called chromatin, in which the DNA is inaccessible, and must be unpacked for DNA to be accessible for transcription or replication. The dynamic conversion between inaccessible and accessible chromatin states is directed by protein complexes that write and read chemical marks on the chromatin called epigenetic modifications. Writing in Nature, Xue et al.1 describe the nucleosome-bound structure of members of the MLL family of proteins: complexes that add methyl groups to histone proteins. The new structures show how these protein complexes both write and read epigenetic modifications.


....

A key to unlocking chromatin revealed by complex structures | Nature

Han Xue, Tonghui Yao, Mi Cao, Guanjun Zhu, Yan Li, Guiyong Yuan, Yong Chen, Ming Lei & Jing Huang. Structural basis of nucleosome recognition and modification by MLL methyltransferases. Nature (2019). DOI: 10.1038/s41586-019-1528-1​

 

[JSCh]

Chinese Scientists Create the Smallest, Atomically-precise and Custom-design Graphene Origami
Sep 06, 2019

The discovery of fullerenes (Nobel Prize in Chemistry 1996), carbon nanotubes (CNT), and, more recently, the isolation of monolayer graphene (Nobel Prize in Physics, 2010) sparked a revolution in the fabrication of a variety of carbon allotropes. Graphene can be viewed as the building block of several allotropes, e.g., carbon nanotubes, three-dimensional (3D) graphene-based nanostructures (GNSs) and devices that have been either fabricated or predicted theoretically for potential applications, even machines.

Origami, the ancient art of paper folding, has been widely used in diverse areas, from architecture to battery design and DNA nanofabrication. It has also inspired the fabrication or simulation of macroscale origami graphene structures and devices, even machines. However, due to technical difficulties, atomically precise and controllable graphene origami for the creation of custom-design GNSs with quantum features has remained an open challenge.

Recently, Professor GAO Hongjun's group from the Institute of Physics of the Chinese Academy of Science, demonstrated that origami is an efficient way to convert graphene nano-fragments into complex nanostructures with atomic-scale precision. By scanning-tunneling-microscope manipulation at low temperatures, they repeatedly fold and unfold graphene nanoislands (GNIs) along an arbitrarily chosen direction.

A bilayer graphene stack featuring a tunable twist angle and a tubular edge connection between the layers is formed. Folding single-crystal GNIs creates tubular edges with specified chirality, while folding bicrystal GNIs creates well-defined intramolecular junctions (IMJs).

These tubular edges are structurally similar to carbon nanotubes (CNTs) and corresponding IMJs. Measurements of electronic properties combined with quantum calculations, based on atomic models of the structures, determine and explain these properties.

The present paper reports the first experimental construction of the smallest-ever, atomically-precise origami graphene nanostructures together with property measurements and corresponding quantum calculations, establishing a platform for the construction of custom carbon nanostructures with engineered quantum properties and, ultimately, quantum machines.

Furthermore, the results reported in this paper set the stage for the discovery of new and unusual phenomena, as the folded GNIs are composite structures comprising a CNT-like fold and a twisted bilayer graphene. For example, it may be worth exploring the superconductivity of the twisted bilayer graphene part with a magic twist angle attached to either a semiconducting or metallic tube or an IMJ.

This study entitled "Atomically precise, custom-design origami graphene Nanostructures" was published on Science.

This work was performed in collaboration with Professor Sokrates T. Pantelides from Vanderbilt University and Professor Min Ouyang from the University of Maryland in the U.S.A.

This work was financially supported by the National Natural Science Foundation of China, National Key Research and Development Projects of China, and Chinese Academy of Sciences.

Fig. 1 Construction of atomically well-defined folded GNSs by STM origami. (Image by Institute of Physics)

​

Fig.2 Precisely controlled folding of a GNI along preselected directions. (Image by Institute of Physics)

​

Fig.3 Tunable 1D tubular carbon structures with different chirality and electronic properties. (Image by Institute of Physics)

​

Fig. 4 Creation of 1D carbon intramolecular junctions. (Image by Institute of Physics)



Chinese Scientists Create the Smallest, Atomically-precise and Custom-design Graphene Origami---Chinese Academy of Sciences

Hui Chen, Xian-Li Zhang, Yu-Yang Zhang, Dongfei Wang, De-Liang Bao, Yande Que, Wende Xiao, Shixuan Du, Min Ouyang, Sokrates T. Pantelides, Hong-Jun Gao. Atomically precise, custom-design origami graphene nanostructures. Nature (2019). DOI: 10.1126/science.aax7864​

 

[JSCh]

Four scientists win China's 2019 Future Science Prize
Source: Xinhua| 2019-09-09 15:35:12|Editor: huaxia

BEIJING, Sept. 9 (Xinhua) -- Four scientists won the 2019 Future Science Prize, the first Chinese non-governmental science award jointly initiated by groups of scientists and entrepreneurs, the China Science Daily reported Monday.

Shao Feng, a senior researcher from Beijing's National Institute of Biological Sciences, was awarded the prize in life sciences for his discoveries about immune defense against bacterial pathogens.

The research results "not only shed new light on our understanding of innate immune mechanisms but also paved the way for designing potential new therapeutic strategies or vaccines for hard-to-treat bacterial infections and related diseases," according to an announcement by the prize committee last Saturday.

The winners of the prize in physical sciences were Wang Yifang, director of the Institute for High-Energy Physics under the Chinese Academy of Sciences, and Kam-Biu Luk, a professor at University of California, Berkeley. They discovered a new type of neutrino oscillations, which could be the key to understanding the matter-antimatter asymmetry in the Universe.

Wang Xiaoyun, with the Institute for Advanced Study of Tsinghua University, is the first female winner since the prize was established in 2016. She won the prize in mathematics and computer science for her contributions to cryptography by innovating methods to reveal weaknesses of widely used hash functions and make a new generation of hash function standards.

The prize is given in the three categories with 1 million U.S. dollars for each award. Each category has four selected donors, the newspaper said.

Winners of the prize will be selected regardless of their nationalities, as long as their achievements are original and innovative, have long-term significance or have passed the tests of time. In addition, it only awards scientists who have made research achievements in the Chinese mainland, Hong Kong, Macao and Taiwan.

The famous agricultural scientist Yuan Longping, physicist Xue Qikun and biologist Shi Yigong have been awarded the prize before.

 

[JSCh]

Using Nature to Produce a Revolutionary Optical Material
Nanocomposite Protects Against Intense Light, Holds Promise for Expanding High-Speed Optical Networking Capacity

By Jeannie Kever 713-743-0778

September 5, 2019

An international team of researchers has reported a new way to safeguard drones, surveillance cameras and other equipment against laser attacks, which can disable or destroy the equipment. The capability is known as optical limiting.

An international team of researchers has reported a new way to safeguard drones, surveillance cameras and other equipment against laser attacks, which can disable or destroy the equipment. Credit: Pexels

The work, published in the journal Nature Communication, also describes a superior manner of telecom switching without the use of electronics; instead, they use an all-optical method that could improve the speed and capacity of internet communications. That could remove a roadblock in moving from 4GLTE to 5G networks.

The team reported that a material created using tellurium nanorods – produced by naturally occurring bacteria – is an effective nonlinear optical material, capable of protecting electronic devices against high-intensity bursts of light, including those emitted by inexpensive household lasers targeted at aircraft, drones or other critical systems. The researchers describe the material and its performance as a material of choice for next-generation optoelectronic and photonic devices.

Bacillus beveridgei strain MLTeJB, composed of aggregated Te(0) shards; The bacteria are readily evident as are the surrounding rods. Credit: USGS

Seamus Curran, a physics professor at the University of Houston and one of the paper’s authors, said while most optical materials are chemically synthesized, using a biologically-based nanomaterial proved less expensive and less toxic. “We found a cheaper, easier, simpler way to manufacture the material,” he said. “We let Mother Nature do it.”

The new findings grew out of earlier work by Curran and his team, working in collaboration with Werner J. Blau of Trinity College Dublin and Ron Oremland with the U.S. Geological Survey. Curran initially synthesized the nanocomposites to examine their potential in the photonics world. He holds a U.S. and international series of patents for that work.

The researchers noted that using bacteria to create the nanocrystals suggests an environmentally friendly route of synthesis, while generating impressive results. “Nonlinear optical measurements of this material reveal the strong saturable absorption and nonlinear optical extinctions induced by Mie scattering overbroad temporal and wavelength ranges,” they wrote. “In both cases, Te [tellurium] particles exhibit superior optical nonlinearity compared to graphene.”

Light at very high intensity, such as that emitted by a laser, can have unpredictable polarizing effects on certain materials, Curran said, and physicists have been searching for suitable nonlinear materials that can withstand the effects. One goal, he said, is a material that can effectively reduce the light intensity, allowing for a device to be developed that could prevent damage by that light.

The researchers used the nanocomposite, made up of biologically generated elemental tellurium nanocrystals and a polymer to build an electro-optic switch – an electrical device used to modulate beams of light – that is immune to damage from a laser, he said.

Oremland noted that the current work grew out of 30 years of basic research, stemming from their initial discovery of selenite-respiring bacteria and the fact that the bacteria form discrete packets of elemental selenium. “From there, it was a step down the Periodic Table to learn that the same could be done with tellurium oxyanions,” he said. “The fact that tellurium had potential application in the realm of nanophotonics came as a serendipitous surprise.”

Blau said the biologically generated tellurium nanorods are especially suitable for photonic device applications in the mid-infrared range. “This wavelength region is becoming a hot technological topic as it is useful for biomedical, environmental and security-related sensing, as well as laser processing and for opening up new windows for fiber optical and free-space communications.”

Work will continue to expand the material’s potential for use in all-optical telecom switches, which Curran said is critical in expanding broadband capacity. “We need a massive investment in optical fiber,” he said. “We need greater bandwidth and switching speeds. We need all-optical switches to do that.”

In addition to Curran, Oremland and Blau, researchers involved with the project include Kang-Shyang Liao and Surendra Maharjan, both of UH; Kangpeng Wang, Xiaoyan Zhang, Ivan M. Kislyakov, Ningning Dong, Saifeng Zhang, Gaozhong Wang, Jintai Fan, Long Zhang, Jun Wang, Xiao Zou, Hongzhou Zhang, Juan Du, Yuxin Leng and Quanzhong Zhao, all with the Shanghai Institute of Optics and Fine Mechanics at the Chinese Academy of Sciences; Kan Wu and Jianping Chen, both with Shanghai Jiao Tong University; and Shaun M. Baesman with the U.S. Geological Survey.

Kangpeng Wang has an additional affiliation with the Technion-Israel Institute of Technology and Gaozhong Wang is also affiliated with Trinity College.


Using Nature to Produce a Revolutionary Optical Material - University of Houston

Kangpeng Wang, Xiaoyan Zhang, Ivan M. Kislyakov, Ningning Dong, Saifeng Zhang, Gaozhong Wang, Jintai Fan, Xiao Zou, Juan Du, Yuxin Leng, Quanzhong Zhao, Kan Wu, Jianping Chen, Shaun M. Baesman, Kang-Shyang Liao, Surendra Maharjan, Hongzhou Zhang, Long Zhang, Seamus A. Curran, Ronald S. Oremland, Werner J. Blau, Jun Wang. Bacterially synthesized tellurium nanostructures for broadband ultrafast nonlinear optical applications. Nature Communications, 2019; 10 (1) DOI: 10.1038/s41467-019-11898-z​

 

[JSCh]

NEWS AND VIEWS * 09 SEPTEMBER 2019
The structure of a T-cell mechanosensor
T-cell receptors orchestrate immune-system responses against infection and cancer. A structure of an entire T-cell receptor complex clarifies its assembly and signalling, and sheds light on its dynamic ligand recognition.

Ellis L. Reinherz

Immune cells called T cells have T-cell receptors (TCRs) on their cell membrane that recognize dysfunctional cells expressing abnormal protein fragments. Such abnormalities can arise in cells if, for example, cancer develops or infection occurs. When TCRs recognize these unusual peptides, the receptors become activated and stimulate T cells to destroy or inhibit the abnormal cells. Such T-cell responses are being harnessed for anti-cancer clinical therapies. TCRs are also of interest because their dysfunction can lead to autoimmunity or immunodeficiency diseases.

Writing in Nature, Dong et al.1 present the structure of a human TCR, at a resolution of 3.7 ångströms, obtained using an imaging technique called single-particle cryogenic electron microscopy (cryoEM). Such a high-resolution structure of the entire TCR was previously lacking, and it provides a wealth of detail about this receptor.


....

The structure of a T-cell mechanosensor | Nature

De Dong, Lvqin Zheng, Jianquan Lin, Bailing Zhang, Yuwei Zhu, Ningning Li, Shuangyu Xie, Yuhang Wang, Ning Gao, Zhiwei Huang. Structural basis of assembly of the human TCR–CD3 complex, Nature (2019). DOI: 10.1038/s41586-019-1537-0​

 

[JSCh]

NEWS * 11 SEPTEMBER 2019
Scientists use gene-edited stem cells to treat HIV — with mixed success
Modified cells survived 19 months after transplant into an HIV-positive man in China, but the dose was not enough to reduce his viral load.

Jonathan Lambert

HIV destroys the body's defences by attacking immune cells. Credit: Steve Gschmeissner/Science Photo Library

For the first time, researchers have used CRISPR gene-editing technology to try to treat a person infected with HIV.

Scientists in China engineered human stem cells to mimic a rare form of natural immunity to the virus and transplanted them into a man with HIV and blood cancer. The gene-edited cells survived in the man’s body for more than a year without causing detectable side effects, but the number of cells was not high enough to significantly reduce the amount of HIV in his blood.

“This is an important step towards using gene editing to treat human disease,” says Fyodor Urnov, a biologist at the University of California, Berkeley. “Because of this study, we now know that these edited cells can survive in a patient, and they will stay there.”

The study1 was published on 11 September in the New England Journal of Medicine. Lead author Hongkui Deng, a biologist at Peking University in Beijing, says that the research was inspired by a remarkable bone-marrow transplant that seemingly cured a man of HIV more than a decade ago.

Mutant power
In 2007, Timothy Ray Brown ― initially known as ‘the Berlin patient’ ― underwent a bone-marrow transplant to treat his leukaemia. The bone-marrow donor was special, however, in that he had a version of the CCR5 gene that confers immunity to HIV.

Normally, the gene encodes a receptor on the surface of white blood cells that the HIV virus uses to infiltrate cells. But in people with two copies of the CCR5 mutation, this receptor is warped and blocks certain strains of HIV from entering cells. The HIV-resistant version of the gene is exceptionally rare: it’s found in just 1% of people of European descent, and is virtually nonexistent in other ethnic groups.

Doctors hoped that the bone-marrow transplant would replace Brown’s HIV-susceptible blood cells with immune ones — and it did. After nearly 13 years, there is no sign of HIV in his blood, and his leukaemia is in remission. In March, researchers reported that a second person underwent a similar procedure in Britain and was cured2.

Deng wanted to use CRISPR gene editing to engineer HIV-resistant blood stem cells from normal donors, making this potential cure more widely accessible. He and his colleagues tested this approach on a 27-year-old man in China who had been diagnosed with HIV and leukaemia, and who needed a bone-marrow transplant. The scientists extracted bone-marrow stem cells from a donor and used CRISPR–Cas9 to transform them into CCR5 mutants.

At first, the researchers couldn’t get CRISPR to knock out CCR5 in the stem cells. “I thought, wow, these cells are really tough,” says Deng. Eventually, the were able to edit 17.8% of the donor’s stem cells.

Safety first
To maximize the chance that the transplant would treat the patient’s cancer, the researchers mixed the edited stem cells with unedited ones. The team monitored the man after the transplant to see whether the edited cells would survive and replicate, whether they treated the HIV infection and, most importantly, whether the treatment was safe.

“This was the first trial, so the most important thing was to test safety,” says Deng.

CRISPR gene editing in people remains controversial, in part because many researchers worry about its side effects. Studies have shown that CRISPR sometimes creates unwanted mutations in the lab3 — and the consequences of that happening in a person could be disastrous.

After 19 months, the CRISPR-edited stem cells did persist, though they comprised only 5–8% of the recipient’s total stem cells. This means that a little over one-half of the edited cells died after they were transplanted. And although the man’s leukaemia is in remission, he is still infected with HIV.

“I’m not surprised that 5% was not enough to lower the viral load,” says Urnov, “but now we know that CRISPR-edited cells can persist, and that we need to do better than 5%.”

To Deng, the most important thing is that the man did not suffer any side effects caused by the gene-edited cells. And when the researchers sequenced the genomes of those cells, they didn’t find evidence of unintended genetic changes.

Pushing forward
“This is really good news for the field,” says Carl June, an immunologist at the University of Pennsylvania in Philadelphia. “We now know that, in principle, we can use CRISPR to edit human stem cells, that they can persist in a patient and that it can be safe.”

June says that this proof of concept opens the door for research into testing this technology for treatment of other blood diseases, such as sickle-cell anaemia. He also notes that this study complied with standard ethical protocols, including obtaining informed consent from the participant.

Improvements in gene-editing technology mean researchers can now edit stem cells with efficiency greater than the 17.8% success rate in the latest study. But that comes with risks. Each time CRISPR cuts in the genome, there's a chance something could go wrong. Gene-editing cells more efficiently means making more cuts, and creates more opportunity for mistakes.

“This paper is an incomplete success, but it will only motivate the field to push onwards,” says Urnov. Had the experiment proved to be unsafe, regulatory agencies might have stopped future research. Now, he says, researchers can point to this study as proof of concept that this line of research can be safe and potentially fruitful.

“I’m going to have an extra scoop of ice cream tonight, knowing that the ship of human genome editing for treating disease is still on course,” says Urnov.

doi: 10.1038/d41586-019-02719-w



Scientists use gene-edited stem cells to treat HIV — with mixed success | Nature

Lei Xu, M.D., Ph.D., Jun Wang, M.D., Ph.D., Yulin Liu, B.S., Liangfu Xie, B.S., Bin Su, Ph.D., Danlei Mou, M.D., Ph.D., Longteng Wang, B.S., Tingting Liu, M.D., Xiaobao Wang, B.S., Bin Zhang, M.D., Ph.D., Long Zhao, Ph.D., Liangding Hu, M.D., Hongmei Ning, M.D., Ph.D., Yufeng Zhang, B.S., Kai Deng, Ph.D., Lifeng Liu, Ph.D., Xiaofan Lu, Ph.D., Tong Zhang, M.D., Ph.D., Jun Xu, Ph.D., Cheng Li, Ph.D., Hao Wu, M.D., Hongkui Deng, Ph.D., and Hu Chen, M.D., Ph.D. CRISPR-Edited Stem Cells in a Patient with HIV and Acute Lymphocytic Leukemia. N Engl J Med (2019); DOI: 10.1056/NEJMoa1817426.​

 

[JSCh]

Welcome indoors, solar cells - Linköping University
16 September 2019
Monica Westman Svenselius

Swedish and Chinese scientists have developed organic solar cells optimised to convert ambient indoor light to electricity. The power they produce is low, but is probably enough to feed the millions of products that the internet of things will bring online.

Wuming Wang, PhD Student, and Jonas Bergqvist, Principal Research Engineer in the solar cell laboratory Thor Balkhed​

As the internet of things expands, it is expected that we will need to have millions of products online, both in public spaces and in homes. Many of these will be the multitude of sensors to detect and measure moisture, particle concentrations, temperature and other parameters. For this reason, the demand for small and cheap sources of renewable energy is increasing rapidly, in order to reduce the need for frequent and expensive battery replacements.

This is where organic solar cells come in. Not only are they flexible, cheap to manufacture and suitable for manufacture as large surfaces in a printing press, they have one further advantage: the light-absorbing layer consists of a mixture of donor and acceptor materials, which gives considerable flexibility in tuning the solar cells such that they are optimised for different spectra – for light of different wavelengths.

New combination of materials
Researchers in Beijing, China, led by Jianhui Hou, and Linköping, Sweden, led by Feng Gao, have now together developed a new combination of donor and acceptor materials, with a carefully determined composition, to be used as the active layer in an organic solar cell. The combination absorbs exactly the wavelengths of light that surround us in our living rooms, at the library and in the supermarket.

The researchers describe two variants of an organic solar cell in an article in Nature Energy, where one variant has an area of 1 cm2 and the other 4 cm2. The smaller solar cell was exposed to ambient light at an intensity of 1000 lux, and the researchers observed that as much as 26.1% of the energy of the light was converted to electricity. The organic solar cell delivered a high voltage of above 1 V for more than 1000 hours in ambient light that varied between 200 and 1000 lux. The larger solar cell still maintained an energy efficiency of 23%.

“This work indicates great promise for organic solar cells to be widely used in our daily life for powering the internet of things”, says Feng Gao, senior lecturer in the Division of Biomolecular and Organic Electronics at Linköping University.

Design rules
”We are confident that the efficiency of organic solar cells will be further improved for ambient light applications in coming years, because there is still a large room for optimization of the materials used in this work”, Jianhui Hou, professor at the Institute of Chemistry, Chinese Academy of Sciences, underlines.

The result is a further advance in research within the field of organic solar cells. In the summer of 2018, for example, the scientists, together with colleagues from a number of other universities, published rules for the construction of efficient organic solar cells (see the link given below). The article collected 25 researchers from seven universities, and was published in Nature Materials. The research was led by Feng Gao. These rules have proven to be useful along the complete pathway to efficient solar cell for indoor use.

Spin off company
The Biomolecular and Organic Electronics research group at Linköping University, under the leadership of Olle Inganäs (now professor emeritus), has been for many years a world-leader in the field of organic solar cells. A few years ago, Olle Inganäs and his colleague Jonas Bergqvist, who is co-author of the articles in Nature Materials and Nature Energy, founded, and are now co-owners of a company, which focusses on commercialising solar cells for indoor use.


Wide-gap non-fullerene acceptor enabling high-performance organic photovoltaic cells for indoor applications, Yong Cui, Yuming Wang, Jonas Bergqvist, Huifeng Yao, Ye Xu, Bowei Gao, Chenyi Yang, Shaoqing Zhang, Olle Inganäs, Feng Gao and Jianhui Hou, Nature Energy 2019. DOI: 10.1038/s41560-019-0448-5

Translated by George Farrants

 

[JSCh]

NEWS RELEASE 18-SEP-2019
Brain-computer interfaces without the mess
AMERICAN CHEMICAL SOCIETY

A cap containing a new type of EEG electrode can be used to control a toy car with brain waves. CREDIT: Adapted from Nano Letters 2019, DOI: 10.1021/acs.nanolett.9b02019

It sounds like science fiction: controlling electronic devices with brain waves. But researchers have developed a new type of electroencephalogram (EEG) electrode that can do just that, without the sticky gel required for conventional electrodes. Even better, the devices work through a full head of hair. The researchers report the flexible electrodes, which could someday be used in brain-computer interfaces to drive cars or move artificial limbs, in the ACS journal Nano Letters.

Often used to diagnose seizure disorders and other neurological conditions, EEGs are machines that track and record brain wave patterns. To conduct an EEG, technicians typically use a very sticky gel to attach electrodes to different regions of the patient's scalp. However, this gel is difficult to wash out of hair and sometimes irritates the skin. In addition, hair interferes with the electrical signals. Ming Lei, Bo Hong, Hui Wu and colleagues wanted to develop an EEG electrode that is flexible, robust and gel-free. Such an electrode could help patients, but also might allow people to someday control devices with their brains.

To make the electrodes, the researchers placed silver nanowires in a commercially available melamine sponge. The electrodes cost only about 12 cents each to make and could be mass-produced. The team assembled 10 electrodes into a flexible silicon cap and measured their performance when worn by people with shaved or hairy heads. On hairless skin, the new electrodes recorded brain waves as well as conventional ones. What's more, the flexibility of the electrodes allowed them to perform similarly on hairy and hairless skin, unlike the conventional devices. A volunteer wearing the cap could control a toy car with her mind, making it go forward, backward, left or right. The electrodes are mechanically stable through different cycles and movements and are also resistant to heat and sweat, the researchers say.


Brain-computer interfaces without the mess | EurekAlert! Science News

 

[JSCh]

NEWS * 11 SEPTEMBER 2019
Scientists use gene-edited stem cells to treat HIV — with mixed success
Modified cells survived 19 months after transplant into an HIV-positive man in China, but the dose was not enough to reduce his viral load.

Jonathan Lambert

HIV destroys the body's defences by attacking immune cells. Credit: Steve Gschmeissner/Science Photo Library

For the first time, researchers have used CRISPR gene-editing technology to try to treat a person infected with HIV.

Scientists in China engineered human stem cells to mimic a rare form of natural immunity to the virus and transplanted them into a man with HIV and blood cancer. The gene-edited cells survived in the man’s body for more than a year without causing detectable side effects, but the number of cells was not high enough to significantly reduce the amount of HIV in his blood.

“This is an important step towards using gene editing to treat human disease,” says Fyodor Urnov, a biologist at the University of California, Berkeley. “Because of this study, we now know that these edited cells can survive in a patient, and they will stay there.”

The study1 was published on 11 September in the New England Journal of Medicine. Lead author Hongkui Deng, a biologist at Peking University in Beijing, says that the research was inspired by a remarkable bone-marrow transplant that seemingly cured a man of HIV more than a decade ago.

Mutant power
In 2007, Timothy Ray Brown ― initially known as ‘the Berlin patient’ ― underwent a bone-marrow transplant to treat his leukaemia. The bone-marrow donor was special, however, in that he had a version of the CCR5 gene that confers immunity to HIV.

Normally, the gene encodes a receptor on the surface of white blood cells that the HIV virus uses to infiltrate cells. But in people with two copies of the CCR5 mutation, this receptor is warped and blocks certain strains of HIV from entering cells. The HIV-resistant version of the gene is exceptionally rare: it’s found in just 1% of people of European descent, and is virtually nonexistent in other ethnic groups.

Doctors hoped that the bone-marrow transplant would replace Brown’s HIV-susceptible blood cells with immune ones — and it did. After nearly 13 years, there is no sign of HIV in his blood, and his leukaemia is in remission. In March, researchers reported that a second person underwent a similar procedure in Britain and was cured2.

Deng wanted to use CRISPR gene editing to engineer HIV-resistant blood stem cells from normal donors, making this potential cure more widely accessible. He and his colleagues tested this approach on a 27-year-old man in China who had been diagnosed with HIV and leukaemia, and who needed a bone-marrow transplant. The scientists extracted bone-marrow stem cells from a donor and used CRISPR–Cas9 to transform them into CCR5 mutants.

At first, the researchers couldn’t get CRISPR to knock out CCR5 in the stem cells. “I thought, wow, these cells are really tough,” says Deng. Eventually, the were able to edit 17.8% of the donor’s stem cells.

Safety first
To maximize the chance that the transplant would treat the patient’s cancer, the researchers mixed the edited stem cells with unedited ones. The team monitored the man after the transplant to see whether the edited cells would survive and replicate, whether they treated the HIV infection and, most importantly, whether the treatment was safe.

“This was the first trial, so the most important thing was to test safety,” says Deng.

CRISPR gene editing in people remains controversial, in part because many researchers worry about its side effects. Studies have shown that CRISPR sometimes creates unwanted mutations in the lab3 — and the consequences of that happening in a person could be disastrous.

After 19 months, the CRISPR-edited stem cells did persist, though they comprised only 5–8% of the recipient’s total stem cells. This means that a little over one-half of the edited cells died after they were transplanted. And although the man’s leukaemia is in remission, he is still infected with HIV.

“I’m not surprised that 5% was not enough to lower the viral load,” says Urnov, “but now we know that CRISPR-edited cells can persist, and that we need to do better than 5%.”

To Deng, the most important thing is that the man did not suffer any side effects caused by the gene-edited cells. And when the researchers sequenced the genomes of those cells, they didn’t find evidence of unintended genetic changes.

Pushing forward
“This is really good news for the field,” says Carl June, an immunologist at the University of Pennsylvania in Philadelphia. “We now know that, in principle, we can use CRISPR to edit human stem cells, that they can persist in a patient and that it can be safe.”

June says that this proof of concept opens the door for research into testing this technology for treatment of other blood diseases, such as sickle-cell anaemia. He also notes that this study complied with standard ethical protocols, including obtaining informed consent from the participant.

Improvements in gene-editing technology mean researchers can now edit stem cells with efficiency greater than the 17.8% success rate in the latest study. But that comes with risks. Each time CRISPR cuts in the genome, there's a chance something could go wrong. Gene-editing cells more efficiently means making more cuts, and creates more opportunity for mistakes.

“This paper is an incomplete success, but it will only motivate the field to push onwards,” says Urnov. Had the experiment proved to be unsafe, regulatory agencies might have stopped future research. Now, he says, researchers can point to this study as proof of concept that this line of research can be safe and potentially fruitful.

“I’m going to have an extra scoop of ice cream tonight, knowing that the ship of human genome editing for treating disease is still on course,” says Urnov.

doi: 10.1038/d41586-019-02719-w



Scientists use gene-edited stem cells to treat HIV — with mixed success | Nature

Lei Xu, M.D., Ph.D., Jun Wang, M.D., Ph.D., Yulin Liu, B.S., Liangfu Xie, B.S., Bin Su, Ph.D., Danlei Mou, M.D., Ph.D., Longteng Wang, B.S., Tingting Liu, M.D., Xiaobao Wang, B.S., Bin Zhang, M.D., Ph.D., Long Zhao, Ph.D., Liangding Hu, M.D., Hongmei Ning, M.D., Ph.D., Yufeng Zhang, B.S., Kai Deng, Ph.D., Lifeng Liu, Ph.D., Xiaofan Lu, Ph.D., Tong Zhang, M.D., Ph.D., Jun Xu, Ph.D., Cheng Li, Ph.D., Hao Wu, M.D., Hongkui Deng, Ph.D., and Hu Chen, M.D., Ph.D. CRISPR-Edited Stem Cells in a Patient with HIV and Acute Lymphocytic Leukemia. N Engl J Med (2019); DOI: 10.1056/NEJMoa1817426.​

Gene-edited stem cells may help cure AIDS
By Wang Xiaodong | China Daily | Updated: 2019-09-19 07:11

[Photo/IC]

Gene-edited stem cells that are the precursors of blood cells may help cure AIDS patients, a new discovery by Chinese scientists shows, providing new insights into treatment of the serious infectious disease.

In the study, researchers used the stem cells and other progenitor cells that had been gene edited to reduce a protein called CCR5, which serves as a doorway for HIV infection of human cells. The gene-edited cells were transplanted into a patient infected with HIV and with acute lymphoblastic leukemia, a common type of leukemia.

The patient, a 27-year-old Chinese, improved greatly during a 19-month follow-up period and showed almost no symptoms of acute leukemia. In addition, the transplanted gene-edited cells showed resistance to HIV infection during a brief period when the patient stopped taking antiviral drugs, according to the study, published in the New England Journal of Medicine on Sept 11.

Deng Hongkui, a professor in life sciences at Peking University, and a chief researcher involved in the study, said researchers overseas have been trying to use gene-edited stem cells to treat AIDS patients, but the study is the first to have gained initial success in clinical trials of the new methods.

The study started in May 2017 and is continuing, he said.

"The study indicates great potential for gene-editing technologies in the treatment of serious diseases, including AIDS, hemophilia and thalassemia," he said. Thalassemia is an inherited disease in which people have an overload of iron in their bodies.

Previously, scientists from abroad succeeded in treating AIDS patients with transplanted bone marrow cells with a natural genetic mutation in the CCR5 protein that made it immune to HIV infection in the few reported cases. A major reason that such treatment is uncommon is that the genetic mutation is rare among humans, which makes finding the right donor extremely difficult.

A new report involving research led by the University of Cambridge was published in March in Nature. A patient with HIV showed immunity to the virus after receiving bone marrow stem cells from such a donor.

Although researchers achieved successful transplantation and long-term grafts of stem and progenitor cells using the CRISPR gene-editing technique, the efficiency of gene editing using the CCR5 protein is not high, indicating the need for further research into this approach, Deng said.

"The research explored the feasibility and safety of the method," he said. "We need to further improve the efficiency of gene editing and optimize transplantation procedures in our future study, and it is expected that application of the gene-editing technology to clinical use to treat diseases will be accelerated," he said.

Although no adverse results related to the gene editing have been seen in the research, long-term, intensified research is still needed to evaluate the safety of the technology, he said.

The number of people living with HIV worldwide is estimated at 37 million, according to the Joint United Nations Programme on HIV/AIDS.

 

[JSCh]

NEWS RELEASE 19-SEP-2019
Bridge between quantum mechanics and general relativity still possible
UNIVERSITY OF SCIENCE AND TECHNOLOGY OF CHINA

​

Experimental diagram of testing gravitaty induced decoherence of entanglement. CREDIT: provided by University of Science and Technology of China

Quantum mechanics and the general theory of relativity form the bedrock of the current understanding of physics - yet the two theories don't seem to work together. Physical phenomena rely on relationship of motion between the observed and the observer. Certain rules hold true across types of observed objects and those observing, but those rules tend to break down at the quantum level, where subatomic particles behave in strange ways.

An international team of researchers developed a unified framework that would account for this apparent break down between classical and quantum physics, and they put it to the test using a quantum satellite called Micius. They published their results ruling out one version of their theory on Sept 19th in Science.

Micius is part of a Chinese research project called Quantum Experiments at Space Scale (QUESS), in which researchers can examine the relationship with quantum and classical physics using light experiments. In this study, the researchers used the satellite to produce and measure two entangled particles.

"Thanks to the advanced technologies made available by Micius, for the first time in human history, we managed to perform a meaningful quantum optical experiment testing the fundamental physics between quantum theory and gravity," said Jian-Wei Pan, paper author and director of the CAS center for Excellence in Quantum Information and Quantum Physics at the University of Science and Technology of China

The theory Pan and the team tested was that the particles would decorrelate from one another as they passed through separate gravitational regions of Earth. The different gravitational pulls would force a quantum interaction that behaved as classical relativism would - the particle in less gravity would move with less constraint than the one in stronger gravity.

According to Pan, this "event formalism" attempts to present a coherent description of quantum fields as they exist in exotic spacetime, which contains closed time-like curves, and ordinary space time. Event formalism standardized behavior across quantum and classical physics.

"If we did observe the deviation, it would mean that event formalism is correct, and we must substantially revise our understanding of the interplay between quantum theory and gravity theory," Pan said. "However, in our experiment, we ruled out the strong version of event formalism, but there are other versions to test."

The researchers did not see the particles deviate from the expected interactions predicted by the quantum understanding of gravity, but they plan to test a version of their theory that allows for a little more flexibility.

"We ruled out the strong version of event formalism, but a modified model remains an open question," Pan said.

To test this version, Pan and the team will launch a new satellite that will orbit 20 to 60 times higher than Micius to test a wider field of gravity strength.



Bridge between quantum mechanics and general relativity still possible | EurekAlert! Science News

Ping Xu, Yiqiu Ma, Ji-Gang Ren, Hai-Lin Yong, Timothy C. Ralph, Sheng-Kai Liao, Juan Yin, Wei-Yue Liu, Wen-Qi Cai, Xuan Han, Hui-Nan Wu, Wei-Yang Wang, Feng-Zhi Li, Meng Yang, Feng-Li Lin, Li Li, Nai-Le Liu, Yu-Ao Chen, Chao-Yang Lu, Yanbei Chen, Jingyun Fan, Cheng-Zhi Peng, Jian-Wei Pan. Satellite testing of a gravitationally induced quantum decoherence model. Science (2019). DOI: 10.1126/science.aay5820​

 

[Galactic Penguin SST]

Aquaculture in China Dating Back 8,000 Years

Thu Sep 19, 2019 11:34

TEHRAN (FNA)- Researchers analyzed fish bones excavated from the Early Neolithic Jiahu site in Henan Province, China. By comparing the body-length distributions and species-composition ratios of the bones with findings from East Asian sites with present aquaculture, the researchers provide evidence of managed carp aquaculture at Jiahu dating back to 6200-5700 BC.

In a recent study, an international team of researchers analyzed fish bones excavated from the Early Neolithic Jiahu site in Henan Province, China. By comparing the body-length distributions and species-composition ratios of the bones with findings from East Asian sites with present aquaculture, the researchers provide evidence of managed carp aquaculture at Jiahu dating back to 6200-5700 BC.

Despite the growing importance of farmed fish for economies and diets around the world, the origins of aquaculture remain unknown. The Shijing, the oldest surviving collection of ancient Chinese poetry, mentions carp being reared in a pond circa 1140 BC, and historical records describe carp being raised in artificial ponds and paddy fields in East Asia by the first millennium BC. But considering rice paddy fields in China date all the way back to the fifth millennium BC, researchers from Lake Biwa Museum in Kusatu, Japan, the Max Planck Institute for the Science of Human History in Jena, Germany, the Sainsbury Institute for the Study of Japanese Arts and Cultures in Norwich, U.K., and an international team of colleagues set out to discover whether carp aquaculture in China was practiced earlier than previously thought.

Carp farming goes way back in Early Neolithic Jiahu

Jiahu, located in Henan, China, is known for the early domestication of rice and pigs, as well the early development of fermented beverages, bone flutes, and possibly writing. This history of early development, combined with archaeological findings suggesting the presence of large expanses of water, made Jiahu an ideal location for the present study.

Researchers measured 588 pharyngeal carp teeth extracted from fish remains in Jiahu corresponding with three separate Neolithic periods, and compared the body-length distributions with findings from other sites and a modern sample of carp raised in Matsukawa Village, Japan. While the remains from the first two periods revealed unimodal patterns of body-length distribution peaking at or near carp maturity, the remains of Period III (6200-5700 BC) displayed bimodal distribution, with one peak at 350-400 mm corresponding with sexual maturity, and another at 150-200 mm.

This bimodal distribution identified by researchers was similar to that documented at the Iron Age Asahi site in Japan (circa 400 BC -- AD 100), and is indicative of a managed system of carp aquaculture that until now was unidentified in Neolithic China. "In such fisheries," the study notes, "a large number of cyprinids were caught during the spawning season and processed as preserved food. At the same time, some carp were kept alive and released into confined, human regulated waters where they spawned naturally and their offspring grew by feeding on available resources. In autumn, water was drained from the ponds and the fish harvested, with body-length distributions showing two peaks due to the presence of both immature and mature individuals."

Species-composition ratios support findings, indicate cultural preferences

The size of the fish wasn't the only piece of evidence researchers found supporting carp management at Jiahu. In East Asian lakes and rivers, crucian carp are typically more abundant than common carp, but common carp comprised roughly 75% of cyprinid remains found at Jiahu. This high proportion of less-prevalent fish indicates a cultural preference for common carp and the presence of aquaculture sophisticated enough to provide it.

Based on the analysis of carp remains from Jiahu and data from previous studies, researchers hypothesize three stages of aquaculture development in prehistoric East Asia. In Stage 1, humans fished the marshy areas where carp gather during spawning season. In Stage 2, these marshy ecotones were managed by digging channels and controlling water levels and circulation so the carp could spawn and the juveniles later harvested. Stage 3 involved constant human management, including using spawning beds to control reproduction and fish ponds or paddy fields to manage adolescents.

Although rice paddy fields have not yet been identified at Jiahu, the evolution of carp aquaculture with wet rice agriculture seems to be connected, and the coevolution of the two is an important topic for future research.

http://web.archive.org/web/20190920...s/Images/1398/06/28/13980628000138_PhotoI.jpg
▲ 1. Carp aquaculture at Jiahu dating back to 6200-5700 BC.

http://web.archive.org/web/20190920033153/https://en.farsnews.com/newstext.aspx?nn=13980628000109
http://archive.fo/MmmvQ

 

[JSCh]

Spotlight: China's achievements in technology innovation draw attention from U.S. tech world
Source: Xinhua| 2019-09-20 04:27:49|Editor: Mu Xuequan

by Xinhua Writer Tan Jingjing

LOS ANGELES, Sept. 19 (Xinhua) -- China's achievements in technology innovation have drawn increasing attention from U.S. media and the high-tech world, and won affirmations from renowned U.S. technology experts.

High-tech China is inventing the next, new thing in frontier technologies: artificial intelligence, biotech, green energy, robotics and superfast and highly functional mobile communications, according to a recent report published by Forbes.

"China is no longer copying from the U.S. Now the reverse is true. Facebook has copied WeChat in private group messaging and followed 15-second video app TikTok. Amazon has imitated Alibaba in e-retailing. Lime has followed China's original Mobike and Ofo brands in bike-sharing," said the report.

In an interview with Xinhua, Eric Topol, a scientist at the renowned Scripps Institute in California, called a ground-breaking electronic chip developed by Chinese scientist a "breakthrough."

The Tianjic chip, which was incorporated into a riderless autonomous bicycle, can detect and track targets, avoid obstacles, self-balance, understand voice commands and even make independent decisions as a result of the chip's simultaneous processing of versatile algorithms and models.

"It's not the first self-driving bike. But equipped with an AI chip, it may be the nearest to thinking for itself," said an article published on The New York Times, titled "And Now, a Bicycle Built for None."

Topol said China is also forging new ground in applying AI to clinical practice.

"The Chinese government has made an extensive commitment to support health AI, reflected by billions of dollars of investment and the designation of one of its five national AI labs specifically for clinical applications," he said.

To take full advantage of deep-learning solutions in healthcare, the United States and China should collaborate, not compete, Topol stressed.

The cooperation between the United States and China could not only drive AI momentum across the globe, but also accelerate the creation of a global research and health infrastructure in which harmonized ethical and regulatory standards facilitate sharing of health data and potentiate deep learning, he said.

An increasing number of U.S. high-tech companies and academic institutions have partnered with Chinese enterprises and institutions along with China's tech advancement.

U.S. tech giant Qualcomm announced strategic cooperation with China's Tencent Games in July this year in the field of digital entertainment. By utilizing Qualcomm Technologies key products and technologies based on Snapdragon platforms, and Tencent's game development expertise and resources, both parties aim to develop popular, high quality games that can be experienced by consumers across a variety of Snapdragon platforms and devices.

Frank Meng, chairman of Qualcomm China, told Xinhua that Qualcomm values the Chinese market and maintains very close cooperation with Chinese partners.

Mobile gaming, an important 5G use case, will soon take advantage of the next generation of connectivity, he said, adding that faster speeds, more bandwidth, and cutting edge ultra-low latency will support real-time, multi-player and immersive gaming experience.

"We look forward to this new cooperation with Tencent Games to enrich lives and transform gaming behaviors on a global scale," he said in an interview with Xinhua.

The Research Methods and Data Science (RMDS) Lab, a U.S. leading community-centered data science research organization headquartered in Pasadena, California, has signed strategic cooperation agreement with China's National Engineering Laboratory of Industrial Big Data Application Technology and the Innovation Center of Industrial Big Data, on joint scientific research, personnel training, resources sharing and other technology solutions.

"China has the world's largest application market for industrial manufacturing. We are confident and optimistic about the great potential of our cooperation with Chinese partners," Alex Liu, founder of RMDS Lab and Chief Data Scientist of IBM, told Xinhua.

Liu said China leads the world in technologies in such areas as face recognition, smart city management, mobile payment and tagging data.

He attributed China's rapid science and technology progress to the government's input and support, innovation of high-tech companies, the reference of foreign experience, and the sound environment of the public to accept new technologies.

Patent applications from China have risen to 22 percent of the world's total, compared to 23 percent for the United States. Chinese research and development spending is quickly catching up to the U.S. level. China already has the world lead on academic scientific papers and the speediest supercomputers, according to U.S. media reports.