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A team of chemists built the first artificial assembler, which uses light as the energy source. These molecular machines are performing synthesis in a similar way as biological nanomachines. Advantages are fewer side products, enantioselectivity, and shorter synthetic pathways since the mechanosynthesis forces the molecules into a predefined reaction channel.

Chemists usually synthesize molecules using stochastic bond-forming collisions of the reactant molecules in solution. Nature follows a different strategy in biochemical synthesis. The majority of biochemical reactions are driven by machine-type protein complexes that bind and position the reactive molecules for selective transformations. Artificial “molecular assemblers” performing “mechanosynthesis” have been proposed as a new paradigm in chemistry and nanofabrication. A team of chemists at Kiel University (Germany) built the first artificial assembler, that performs synthesis and uses light as the energy source. The system combines selective binding of the reactants, accurate positioning, and active release of the product. The scientists published their findings in the journal Communications Chemistry.

The idea of molecular assemblers, that are able to build molecules, has already been proposed in 1986 by K. Eric Drexler, based on ideas of Richard Feynman, Nobel Laureate in Physics. In his book “Engines of Creation: The Coming Era of Nanotechnology” and follow-up publications Drexler proposes molecular machines capable of positioning reactive molecules with atomic precision and to build larger, more sophisticated structures via mechanosynthesis. If such a molecular nanobot could build any molecule, it could certainly build another copy of itself, i.e. it could self-replicate. These imaginative visions inspired a number of science fiction authors, but also started an intensive scientific controversy.

The rules about what makes a good magnet may not be as rigid as scientists thought. Using a mixture containing magnetic nanoparticles, researchers have now created liquid droplets that behave like tiny bar magnets.

Magnets that generate persistent magnetic fields typically are composed of solids like iron, where the magnetic poles of densely packed atoms are all locked in the same direction (SN: 2/17/18, p. 18). While some liquids containing magnetic particles can become magnetized when placed in a magnetic field, the magnetic orientations of those free-floating particles tend to get jumbled when the field goes away — causing the liquid to lose its magnetism.

Now, adding certain polymers to their recipe has allowed researchers to concoct permanently magnetized liquid droplets. These tiny, moldable magnets, described in the July 19 Science, could be used to build soft robots or capsules that can be magnetically steered through the body to deliver drugs to specific cells.

A new wireless transceiver invented by electrical engineers at the University of California, Irvine boosts radio frequencies into 100-gigahertz territory, quadruple the speed of the upcoming 5G, or fifth-generation, wireless communications standard.

Labeled an “end-to-end transmitter-receiver” by its creators in UCI’s Nanoscale Communication Integrated Circuits Labs, the 4.4-millimeter-square silicon chip is capable of processing digital signals significantly faster and more energy-efficiently because of its unique digital-analog architecture. The team’s innovation is outlined in a paper published recently in the IEEE Journal of Solid-State Circuits.

“We call our chip ‘beyond 5G’ because the combined speed and data rate that we can achieve is two orders of magnitude higher than the capability of the new wireless standard,” said senior author Payam Heydari, NCIC Labs director and UCI professor of electrical engineering & computer science. “In addition, operating in a higher frequency means that you and I and everyone else can be given a bigger chunk of the bandwidth offered by carriers.”

One of the main speculations about future technology is uploading. This is where our minds are copied in exact detail from our biological physical bodies and then created in artificial bodies. Alexander Bolonkin has posited many kinds of technology over the decades. He has a recent work which is summarized here where he considers that future uploading will mean that we can then use super-technology (nanotechnology, nuclear fusion etc…) to make people into literal gods and supermen. We can use control of matter, energy and information to make what he calls the E-man. Bolonkin then indicates that uploading and creation of minds could be used for the resurrection of long-dead people. This would be where we create the very close approximation of dead people. This would be like using gene editing to turn an African Elephant into a Whooly Mammoth. The vast technological capability would let us actualize what would be a simulation into living entities.

Bolonkin’s Case for E-Man and Resurrection

Alexander Bolonkin looks at methods and possibilities for electronic resurrection of long-dead outstanding personalities. He also considers the principles and organization of the new E-society, its goals and conditions of existence.

Researchers at Tufts University and the Chinese Academy of Sciences have developed a new lipid nanoparticle which can deliver CRISPR/Cas9 gene editing tools into organs with high efficiency, suggesting that the system is promising for clinical applications.

The CRISPR/Cas9 system is currently being investigated as a way to treat a variety of diseases with a genetic basis, including Duchenne muscular dystrophy, Huntington’s, and sickle cell disease. While the system has significant promise, there are some issues that need to be resolved before it can be used clinically. CRISPR/Cas9 is a large complex, and it is difficult to get it inside cell nuclei where it is needed for gene editing.

Scientists have tried a variety of delivery vehicles for CRISPR/Cas, which are intended to carry the gene editing tools to their location and help them enter the cell and nucleus. These have included viruses and various types of nanoparticle. However, to date, these have suffered from low efficiency, whereby very little of the delivered agent reaches the cells or organs where it is needed.

Ferrofluids, with their mesmeric display of shape-shifting spikes, are a favorite exhibit in science shows. These eye-catching examples of magnetic fields in action could become even more dramatic through computational work that captures their motion.

A KAUST research team has now developed a computer model of motion that could be used to design even grander ferrofluid displays. The work is a stepping stone to using to inform the use of ferrofluids in broad range of practical applications, such as medicine, acoustics, radar-absorbing materials and nanoelectronics.

Ferrofluids were developed by NASA in the 1960s as a way to pump fuels in low gravity. They comprise nanoscale magnetic particles of iron-laden compounds suspended in a liquid. In the absence of a magnetic , ferrofluids possess a perfectly smooth surface. But when a magnet is brought close to the ferrofluid, the particles rapidly align with the magnetic field, forming the characteristic spiky appearance. If a magnetic object is placed in the ferrofluid, the spikes will even climb the object before cascading back down.

The environment contains electromagnetic radiation and magnetic fields of natural and artificial origin. Even a short electromagnetic pulse is enough to knock any equipment out of operation. Candidate of Sciences (Physics and Mathematics) Aleksey Trukhanov, senior research fellow at the SUSU Nanotechnologies Research and Education Center, is studying electrolytic films to develop electromagnetic and magnetic shields capable of neutralizing this radiation.

“The issue of electromagnetic compatibility of devices is very topical today. One of the most popular methods of equipment protection used around the world is shielding—creating electromagnetic and magnetic shields. But every developer has his own design approaches and secrets, which he naturally wouldn’t share. Suffice it to say that the cost of products with and without protective shielding may differ tenfold and more,” says Trukhanov.

Normally, heavy elements are used as the material for shielding, as they efficiently absorb high-energy radiation. Bismuth is a heavy metal with high density and high number of shell electrons. This makes it analogous to such widely used materials as lead. However, in the ratio of the protection efficiency to mass-size parameters (as well as with consideration to the ecological aspect) bismuth is the best option.

If scientists could find a way to control the process for making semiconductor components on a nanometric scale, they could give those components unique electronic and optical properties—opening the door to a host of useful applications.

Researchers at the Laboratory of Microsystems, in EPFL’s School of Engineering, have taken an important step towards that goal with their discovery of semiconducting nanotubes that assemble automatically in solutions of metallic nanocrystals and certain ligands. The tubes have between three and six walls that are perfectly uniform and just a few atoms thick—making them the first such nanostructures of their kind.

What’s more, the nanotubes possess photoluminescent properties: they can absorb light of a specific wavelength and then send out intense light waves of a different color, much like and quantum wells. That means they can be used as in , for example, or as catalysts in photoreduction reactions, as evidenced by the removal of the colors of some organic dyes, based on the results of initial experiments. The researchers’ findings have made the cover of ACS Central Science.

A particularly aggressive, metastasizing form of cancer, HER2-positive breast cancer, may be treated with nanoscopic particles “imprinted” with specific binding sites for the receptor molecule HER2. As reported by Chinese researchers in the journal Angewandte Chemie, the selective binding of the nanoparticles to HER2 significantly inhibits multiplication of the tumor cells.