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May 12, 2021

New atomically precise graphene nanoribbon heterojunction sensor developed

Posted by in categories: particle physics, quantum physics

An international research team led by the University of Cologne has succeeded for the first time in connecting several atomically precise nanoribbons made of graphene, a modification of carbon, to form complex structures. The scientists have synthesized and spectroscopically characterized nanoribbon heterojunctions. They then were able to integrate the heterojunctions into an electronic component. In this way, they have created a novel sensor that is highly sensitive to atoms and molecules. The results of their research have been published under the title Tunneling current modulation in atomically precise graphene nanoribbon heterojunctions’ in Nature Communications. The work was carried out in close cooperation between the Institute for Experimental Physics with the Department of Chemistry at the University of Cologne, as well as with research groups from Montreal, Novosibirsk, Hiroshima, and Berkeley. It was funded by the German Research Foundation (DFG) and the European Research Council (ERC).

The heterojunctions of graphene nanoribbons are just one nanometer—one millionth of a millimeter—wide. Graphene consists of only a single layer of carbon atoms and is considered the thinnest material in the world. In 2010, researchers in Manchester succeeded in making single-atom layers of graphene for the first time, for which they won the Nobel Prize. The heterojunctions used to make the sensor are each seven and fourteen carbon atoms wide and about 50 nanometres long. What makes them special is that their edges are free of defects. This is why they are called atomically precise nanoribbons, explained Dr. Boris Senkovskiy from the Institute for Experimental Physics. The researchers connected several of these nanoribbon heterojunctions at their short ends, thus creating more complex heterostructures that act as tunneling barriers.

The heterostructures were investigated using angle-resolved photoemission, optical spectroscopy, and scanning tunneling microscopy. In the next step, the generated heterostructures were integrated into an electronic device. The flowing through the nanoribbon heterostructure is governed by the quantum mechanical tunneling effect. This means that under certain conditions, electrons can overcome existing energy barriers in atoms by ‘tunneling,’ so that a current then flows even though the barrier is greater than the available energy of the electron.

May 12, 2021

China starts large-scale testing of its internet of the future

Posted by in categories: internet, robotics/AI, security

It will serve as a backbone network for the China Environment for Network Innovations (CENI), a national research facility connecting the largest cities in China, to verify its performance and the security of future network communications technology before commercial use.


Experimental network connects 40 leading universities to prepare for an AI-driven society five to 10 years down the track.

May 12, 2021

Perseverance’s Robotic Arm Starts Conducting Science Program

Posted by in categories: biological, robotics/AI, science, space

NASA’s newest Mars rover is beginning to study the floor of an ancient crater that once held a lake.

NASA’s Perseverance rover has been busy serving as a communications base station for the Ingenuity Mars Helicopter and documenting the rotorcraft’s historic flights. But the rover has also been busy focusing its science instruments on rocks that lay on the floor of Jezero Crater.

What insights they turn up will help scientists create a timeline of when an ancient lake formed there, when it dried, and when sediment began piling up in the delta that formed in the crater long ago. Understanding this timeline should help date rock samples – to be collected later in the mission – that might preserve a record of ancient microbes.

May 12, 2021

Scientists find liquid water inside a meteorite, revealing clues about the early solar system

Posted by in category: space

Scientists have spotted water in a primitive meteorite, expanding our understanding of the ancient solar system.

May 12, 2021

Intel says it has solved a key bottleneck in quantum computing

Posted by in categories: computing, quantum physics

Intel has overcome a quantum computing bottleneck by controlling two qubits with a cryogenic control chip.

May 12, 2021

Hyaluronic acid: A key molecule in skin aging

Posted by in categories: biotech/medical, life extension, sex

Skin aging is a multifactorial process consisting of two distinct and independent mechanisms: intrinsic and extrinsic aging. Youthful skin retains its turgor, resilience and pliability, among others, due to its high content of water. Daily external injury, in addition to the normal process of aging, causes loss of moisture. The key molecule involved in skin moisture is hyaluronic acid (HA) that has unique capacity in retaining water. There are multiple sites for the control of HA synthesis, deposition, cell and protein association and degradation, reflecting the complexity of HA metabolism. The enzymes that synthesize or catabolize HA and HA receptors responsible for many of the functions of HA are all multigene families with distinct patterns of tissue expression. Understanding the metabolism of HA in the different layers of the skin and the interactions of HA with other skin components will facilitate the ability to modulate skin moisture in a rational manner.

Keywords: hyaluronic acid, hyaluronic acid synthases, hyaluronidases, CD44, RHAMM, skin aging.

Human skin aging is a complex biological process, not yet fully understood. It is the result of two biologically independent processes. The first is intrinsic or innate aging, an unpreventable process, which affects the skin in the same pattern as it affects all internal organs. The second is extrinsic aging, which is the result of exposure to external factors, mainly ultraviolet (UV) irradiation, that is also referred to as photoaging.1 Intrinsic skin aging is influenced by hormonal changes that occur with age,2 such as the gradual decreased production of sex hormones from the mid-twenties and the diminution of estrogens and progesterone associated with menopause. It is well established that the deficiency in estrogens and androgens results in collagen degradation, dryness, loss of elasticity, epidermal atrophy and wrinkling of the skin.3

May 12, 2021

Nearly a fifth of Earth’s surface transformed since 1960

Posted by in categories: climatology, sustainability

Whether it’s turning forests into cropland or savannah into pastures, humanity has repurposed land over the last 60 years equivalent in area to Africa and Europe combined, researchers said Tuesday.

If you count all such transitions since 1960, it adds up to about 43 million square kilometres (16.5 square miles), four times more than previous estimates, according to a study in Nature Communications.

“Since land use plays a central role for climate mitigation, biodiversity and food production, understanding its full dynamics is essential for sustainable land use strategies,” lead author Karina Winkler, a physical geographer at Wageningen University & Research in the Netherlands, told AFP.

May 12, 2021

Gasoline Buying Fever Rages as Pipeline Company Begins Restart

Posted by in category: energy

While drivers scrambled for fuel, Colonial Pipeline said supplies would resume flowing from Texas to the East Coast in the coming days.

May 12, 2021

Chevy’s Chaparral GT6 Concept Is a Real Thing with Theoretical Laser-Based Propulsion

Posted by in category: transportation

O,., o!Awesome: 3.


Chevrolet built a full-scale version of its Gran Turismo 6 concept—and it has a wild, theoretical drivetrain.

May 12, 2021

Mind over matter: brain chip allows paralysed man to write

Posted by in categories: computing, mobile phones, neuroscience

Tokyo (AFP)

Paralysed from the neck down, the man stares intently at a screen. As he imagines handwriting letters, they appear before him as typed text thanks to a new brain implant.

The 65-year-old is “typing” at a speed similar to his peers tapping on a smartphone, using a device that could one day help paralysed people communicate quickly and easily.