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3D printing technique accelerates nanoscale fabrication 1000-fold

Using a new time-based method to control light from an ultrafast laser, researchers have developed a nanoscale 3D printing technique that can fabricate tiny structures 1000 times faster than conventional two-photon lithography (TPL) techniques, without sacrificing resolution.

Despite the high throughput, the new parallelized technique—known as femtosecond projection TPL (FP-TPL)—produces depth resolution of 175 nanometers, which is better than established methods and can fabricate structures with 90-degree overhangs that can’t currently be made. The technique could lead to manufacturing-scale production of bioscaffolds, flexible electronics, electrochemical interfaces, micro-optics, mechanical and optical metamaterials, and other functional micro- and nanostructures.

The work, reported Oct. 3 in the journal Science, was done by researchers from Lawrence Livermore National Laboratory (LLNL) and The Chinese University of Hong Kong. Sourabh Saha, the paper’s lead and corresponding author, is now an assistant professor in the George W. Woodruff School of Mechanical Engineering at the Georgia Institute of Technology.

A filament fit for space—silk is proven to thrive in outer space temperatures

Their initial discovery had seemed like a contradiction because most other polymer fibres embrittle in the cold. But after many years of working on the problem, the group of researchers have discovered that silk’s cryogenic toughness is based on its nano-scale fibrills. Sub-microscopic order and hierarchy allows a silk to withstand temperatures of down to −200 C. And possibly even lower, which would make these classic natural luxury fibres ideal for applications in the depths of chilly outer-space.

The interdisciplinary team examined the behaviour and function of several animal silks cooled down to liquid nitrogen temperature of −196 C. The fibres included spider silks but the study focused on the thicker and much more commercial fibres of the wild silkworm Antheraea pernyi.

In an article published today in Materials Chemistry Frontiers, the team was able to show not only ‘that’ but also ‘how’ silk increases its toughness under conditions where most materials would become very brittle. Indeed, silk seems to contradict the fundamental understanding of polymer science by not losing but gaining quality under really cold conditions by becoming both stronger and more stretchable. This study examines the ‘how’ and explains the ‘why’. It turns out that the underlying processes rely on the many nano-sized fibrils that make up the core of a silk fibre.

DNA Nanomachines Are Opening Medicine to the World of Physics

When I imagine the inner workings of a robot, I think hard, cold mechanics running on physics: shafts, wheels, gears. Human bodies, in contrast, are more of a contained molecular soup operating on the principles of biochemistry.

Yet similar to robots, our cells are also attuned to mechanical forces—just at a much smaller scale. Tiny pushes and pulls, for example, can urge stem cells to continue dividing, or nudge them into maturity to replace broken tissues. Chemistry isn’t king when it comes to governing our bodies; physical forces are similarly powerful. The problem is how to tap into them.

In a new perspectives article in Science, Dr. Khalid Salaita and graduate student Aaron Blanchard from Emory University in Atlanta point to DNA as the solution. The team painted a futuristic picture of DNA mechanotechnology, in which we use DNA machines to control our biology. Rather than a toxic chemotherapy drip, for example, a cancer patient may one day be injected with DNA nanodevices that help their immune cells better grab onto—and snuff out—cancerous ones.

SwarmTouch: A tactile interaction strategy for human-swarm communication

Researchers at the Skolkovo Institute of Science and Technology (Skoltech) in Russia have recently introduced a new strategy to enhance interactions between humans and robotic swarms, called SwarmTouch. This strategy, presented in a paper pre-published on arXiv, allows a human operator to communicate with a swarm of nano-quadrotor drones and guide their formation, while receiving tactile feedback in the form of vibrations.

“We are working in the field of swarm of drones and my previous research in the field of haptics was very helpful in introducing a new frontier of tactile human-swarm interactions,” Dzmitry Tsetserukou, Professor at Skoltech and head of Intelligent Space Robotics laboratory, told TechXplore. “During our experiments with the swarm, however, we understood that current interfaces are too unfriendly and difficult to operate.”

While conducting research investigating strategies for human-swarm interaction, Tsetserukou and his colleagues realised that there are currently no available interfaces that allow human operators to easily deploy a swarm of robots and control its movements in real time. At the moment, most swarms simply follow predefined trajectories, which have been set out by researchers before the robots start operating.

A new way to turn heat into energy

An international team of scientists has figured out how to capture heat and turn it into electricity.

The discovery, published last week in the journal Science Advances, could create more efficient generation from heat in things like car exhaust, interplanetary space probes and .

“Because of this discovery, we should be able to make more out of heat than we do today,” said study co-author Joseph Heremans, professor of mechanical and aerospace engineering and Ohio Eminent Scholar in Nanotechnology at The Ohio State University. “It’s something that, until now, nobody thought was possible.”

Novel anti-cancer nanomedicine for efficient chemotherapy

Researchers at the University of Helsinki in collaboration with researchers from Åbo Akademi University (Finland) and Huazhong University of Science and Technology (China) have developed a new anti-cancer nanomedicine for targeted cancer chemotherapy. This new nano-tool provides a new approach to use cell-based nanomedicines for efficient cancer chemotherapy.

Honey I shrunk the kids! Real life ‘shrink ray’ reduces 3D structures to 1/1000th their original size

SCIENTISTS have created a “shrink ray” that can reduce objects to one-thousandth of their original size.

The mind-blowing gizmo could one day be used to create nano-robots that are smaller that we can physically produce today.

This brings us a step closer to making 1989 sci-fi comedy Honey, I Shrunk the Kids a reality.

Researchers build a quantum dot energy harvester

Over the past few years, thermoelectric generators have become the focus of a growing number of studies, due to their ability to convert waste heat into electrical energy. Quantum dots, semiconductor crystals with distinctive conductive properties, could be good candidates for thermoelectric generation, as their discrete resonant levels provide excellent energy filters.

In a recent study, researchers at the University of Cambridge, in collaboration with colleagues in Madrid, Rochester, Duisburg and Sheffield, have experimentally demonstrated the potential of an autonomous nanoscale harvester based on resonant tunneling quantum dots. This harvester is based on previous research carried out by part of their team, who had proposed a three-terminal energy harvester based on two resonant-tunneling quantum dots with different energy levels.

The energy harvester device was realized at Cavendish Laboratory in Cambridge by a researcher called Gulzat Jaliel. The original theoretical proposal for the device, however, was introduced by Andrew Jordan in 2013, and the theoretical work behind the harvester was carried out by him in collaboration with renowned semiconductor physicist Markus Büttiker and a team of post-doctoral students in Geneva.

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