Lifeboat Foundation: Safeguarding Humanity
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Category: nanotechnology – Page 219

CIEQSFTTLFACQTAAEIWRAFGYTVKIMVDNGNCRLHVC: these forty letters are a set of instructions for building a sophisticated medical device designed to recognize the flu virus in your body. The device latches onto the virus and deactivates the part of it that breaks into your cells. It is impossibly tiny—smaller than the virus on which it operates—and it can be manufactured, in tremendous quantities, by your own cells. It’s a protein.

Proteins—molecular machines capable of building, transforming, and interacting with other molecules—do most of the work of life. Antibodies, which defend our cells against invaders, are proteins. So are hormones, which deliver messages within us; enzymes, which carry out the chemical reactions we need to generate energy; and the myosin in our muscles, which contract when we move. A protein is a large molecule built from smaller molecules called amino acids. Our bodies use twenty amino acids to create proteins; our cells chain them together, following instructions in our DNA. (Each letter in a protein’s formula represents an amino acid: the first two in the flu-targeting protein above are cysteine and isoleucine.) After they’re assembled, these long chains crumple up into what often look like random globs. But the seeming chaos in their collapse is actually highly choreographed. Identical strings of amino acids almost always “fold” into identical three-dimensional shapes. This reliability allows each cell to create, on demand, its own suite of purpose-built biological tools. “Proteins are the most sophisticated molecules in the known universe,” Neil King, a biochemist at the University of Washington’s Institute for Protein Design (I.P.D.), told me. In their efficiency, refinement, and subtlety, they surpass pretty much anything that human beings can build.

Today, biochemists engineer proteins to fight infections, produce biofuels, and improve food stability. Usually, they tweak formulas that nature has already discovered, often by evolving new versions of naturally occurring proteins in their labs. But “de novo” protein design—design from scratch—has been “the holy grail of protein science for many decades,” Sarel Fleishman, a biochemist at the Weizmann Institute of Science, in Israel, told me. Designer proteins could help us cure diseases; build new kinds of materials and electronics; clean up the environment; create and transform life itself. In 2018, Frances Arnold, a chemical engineer at the California Institute of Technology, shared the Nobel Prize in Chemistry for her work on protein design. In April, when the coronavirus pandemic was peaking on the coasts, we spoke over video chat. Arnold, framed by palm trees, sat outside her home, in sunny Southern California. I asked how she thought about the potential of protein design. “Well, I think you just have to look at the world behind me, right?” she said. “Nature, for billions of years, has figured out how to extract resources from the environment—sunlight, carbon dioxide—and convert those into remarkable, living, functioning machines. That’s what we want to do—and do it sustainably, right? Do it in a way that life can go on.”

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Modern construction is a precision endeavor. Builders must use components manufactured to meet specific standards — such as beams of a desired composition or rivets of a specific size. The building industry relies on manufacturers to create these components reliably and reproducibly in order to construct secure bridges and sound skyscrapers.

Now imagine construction at a smaller scale — less than 1/100th the thickness of a piece of paper. This is the nanoscale. It is the scale at which scientists are working to develop potentially groundbreaking technologies in fields like quantum computing. It is also a scale where traditional fabrication methods simply will not work. Our standard tools, even miniaturized, are too bulky and too corrosive to reproducibly manufacture components at the nanoscale.

Researchers at the University of Washington have developed a method that could make reproducible manufacturing at the nanoscale possible. The team adapted a light-based technology employed widely in biology — known as optical traps or optical tweezers — to operate in a water-free liquid environment of carbon-rich organic solvents, thereby enabling new potential applications.

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Though the Summer Olympics were postponed, there’s at least one place to see agile hurdlers go for the gold.

You just need a way to view these electron games.

Using a novel optical detection system, researchers at Rice University found that electricity generated by temperature differences doesn’t appear to be affected measurably by placed in its way in nanoscale gold wires, while strain and other defects in the material can change this “thermoelectric” response.

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Gold isn’t just a pretty face – it’s shown promise in fighting cancer in many studies. Now researchers have found a way to grow gold nanoparticles directly inside cancer cells within 30 minutes, which can help with imaging and even be heated up to kill the tumors.

Gold isn’t just a pretty face – it’s shown promise in fighting cancer in many studies. Now researchers have found a way to grow gold nanoparticles directly inside cancer cells within 30 minutes, which can help with imaging and even be heated up to kill the tumors.

In previous work, gold nanostars, nanotubes and other nanoparticle structures have been sent into battle against cancer, but one of the main hurdles is getting the stuff inside the tumors. Sometimes they’re equipped with peptides that hunt down cancer, while others sneak in attached to white blood cells.

For this new study, researchers instead found a way to grow the gold directly inside the cancer cells. The advantage is that it doesn’t require as high a concentration of gold in the cell, and it can be done much quicker than other methods.

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Circa 2015

Invisibility cloaks are a staple of science fiction and fantasy, from Star Trek to Harry Potter, but don’t exist in real life, or do they? Scientists at the U.S. Department of Energy (DOE)’s Lawrence Berkeley National Laboratory (Berkeley Lab) and the University of California (UC) Berkeley have devised an ultra-thin invisibility “skin” cloak that can conform to the shape of an object and conceal it from detection with visible light. Although this cloak is only microscopic in size, the principles behind the technology should enable it to be scaled-up to conceal macroscopic items as well.

Working with brick-like blocks of gold nanoantennas, the Berkeley researchers fashioned a “skin cloak” barely 80 nanometers in thickness, that was wrapped around a three-dimensional object about the size of a few biological cells and arbitrarily shaped with multiple bumps and dents. The surface of the skin cloak was meta-engineered to reroute reflected waves so that the object was rendered invisible to optical detection when the cloak is activated.

“This is the first time a 3D object of arbitrary shape has been cloaked from ,” said Xiang Zhang, director of Berkeley Lab’s Materials Sciences Division and a world authority on metamaterials — artificial nanostructures engineered with electromagnetic properties not found in nature. “Our ultra-thin cloak now looks like a coat. It is easy to design and implement, and is potentially scalable for hiding macroscopic objects.”

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Physicists from MIPT and the Russian Quantum Center, joined by colleagues from Saratov State University and Michigan Technological University, have demonstrated new methods for controlling spin waves in nanostructured bismuth iron garnet films via short laser pulses. Presented in Nano Letters, the solution has potential for applications in energy-efficient information transfer and spin-based quantum computing.

A particle’s spin is its intrinsic angular momentum, which always has a direction. In magnetized materials, the spins all point in one direction. A local disruption of this magnetic order is accompanied by the propagation of spin waves, whose quanta are known as magnons.

Unlike the electrical current, spin wave propagation does not involve a transfer of matter. As a result, using magnons rather than electrons to transmit information leads to much smaller thermal losses. Data can be encoded in the phase or amplitude of a spin wave and processed via wave interference or nonlinear effects.

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Magnetism offers new ways to create more powerful and energy-efficient computers, but the realization of magnetic computing on the nanoscale is a challenging task. A critical advancement in the field of ultralow power computation using magnetic waves is reported by a joint team from Kaiserslautern, Jena and Vienna in the journal Nano Letters.

A local disturbance in the magnetic order of a magnet can propagate across a material in the form of a wave. These waves are known as spin waves and their associated quasi-particles are called magnons. Scientists from the Technische Universität Kaiserslautern, Innovent e. V. Jena and the University of Vienna are known for their expertise in the called ‘magnonics,’ which utilizes magnons for the development of novel types of computers, potentially complementing the conventional electron-based processors used nowadays.

“A new generation of computers using magnons could be more powerful and, above all, consume less energy. One major prerequisite is that we are able to fabricate, so-called single-mode waveguides, which enable us to use advanced wave-based signal processing schemes,” says Junior Professor Philipp Pirro, one of the leading scientists of the project. “This requires pushing the sizes of our structures into the nanometer range. The development of such conduits opens, for example, an access to the development of neuromorphic computing systems inspired by the functionalities of the human brain.”

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Researchers from China continue in the quest to improve methods for bone regeneration, publishing their findings in “Cryogenic 3D printing of dual-delivery scaffolds for improved bone regeneration with enhanced vascularization.”

A wide range of projects have emerged regarding new techniques for bone regeneration—especially in the last five years as 3D printing has become more entrenched in the mainstream and bioprinting has continued to evolve. Bone regeneration is consistently challenging, and while bioprinting is still relatively new as a field, much impressive progress has been made due to experimentation with new materials, nanotubes, and innovative structures.

Cell viability is usually the biggest problem. Tissue engineering, while becoming much more successful these days, is still an extremely delicate process as cells must not only be grown but sustained in the lab too. For this reason, scientists are always working to improve structures like scaffolds, as they are responsible in most cases for supporting the cells being printed. In this study, the authors emphasize the need for both “excellent osteogenesis and vascularization” in bone regeneration.

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A high-power laser, optimized optical pathway, a patented adaptive resolution technology, and smart algorithms for laser scanning have enabled UpNano, a Vienna-based high-tech company, to produce high-resolution 3D-printing as never seen before.

“Parts with nano- and microscale can now be printed across 12 orders of magnitude—within times never achieved previously. This has been accomplished by UpNano, a spin-out of the TU Wien, which developed a high-end two-photon polymerization (2PP) 3D-printing system that can produce polymeric parts with a volume ranging from 100 to 1012 cubic micrometers. At the same time the printer allows for a nano- and microscale resolution,” the company said in a statement.

Recently the company demonstrated this remarkable capability by printing four models of the Eiffel Tower ranging from 200 micrometers to 4 centimeters—with perfect representation of all minuscule structures within 30 to 540 minutes. With this, 2PP 3D-printing is ready for applications in R&D and industry that seemed so far impossible.

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A team of researchers from the Max Planck Institute for the Science of Light and Friedrich-Alexander University Erlangen has found a way to prove a theory suggesting the possibility of cloaking a nanoparticle using a single molecule—by nearly doing it with a gold nanoparticle and a dibenzoterrylene molecule. In their paper published in the journal Physical Review Letters, the group describes their experiments with coupled nanoparticles and molecules, and what they learned from them.

For several years, scientists have been experimenting with coupling and molecules. In most such work, the nanoparticle (which is generally larger than the molecule) serves as an antenna of sorts, funneling light to the molecule. The goal has been to boost the emissions from the molecule or to absorb the light they receive—both of which can be used to detect biomolecules under certain circumstances. In other work, researchers have looked into the possibility of controlling the emissions coming from the molecule to match the wavelength of the incoming . In theory, if they are in phase, the nanoparticle’s shadow should dissipate or disappear completely—a form of cloaking. In this new effort, the researchers sought to prove this theory by carrying out experiments with nanoparticles and molecules.

The work involved first getting a130-nm-wide gold nanoparticle to couple with a dibenzoterrylene molecule. This involved placing several of the on a surface and then covering them with a solution containing dibenzoterrylene . The setup was then chilled to the point that the solution solidified. The team then used a laser to look for a test nanoparticle-molecule pairing until they found a pair that had closely coupled. They then focused a near-infrared beam on the pair, from the direction of the molecule.

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