SciTech #ScienceSunday Digest, 50/14.Artificial skin, APM nanoparticle clustering, wireless BCIs, solar technology advances, tiny computers, small particle accelerators, self-assembled optical memory, RoboBrain, laser graphene structures, entropy and life.1. Better Artificial Skin.
Improved artificial skin has been developed by combining a new flexible polymer that mimics key properties of normal skin with a dense but flexible array of gold and silicon sensors http://www.technologyreview.com/news/533106/artificial-skin-that-senses-and-stretches-like-the-real-thing/
. This is the most sensitive artificial skin yet, with 400 sensors per square millimeter, and is designed to facilitate the sensing of touch, pressure, temperature, and moisture. Immediate applications are of course for robotics, which need to be better able to sense and interact with the environment, and also for prosthetic limbs for amputees - although developing suitable brain- or nerve-computer-interfaces to convey this information to patients is a work-in-progress, even with promising proof-of-concept demonstrations evident. 2. Fine Control Over Nanoparticle Scale and Clustering.
Combining specific DNA sequences with specific zinc-finger DNA binding proteins that also attach to specific nanoparticles allows fine control over nanoparticle clustering and the directed (self-assembled) fabrication of specific nanoparticle clusters http://phys.org/news/2014-12-nanoparticle-cluster-technique-dna-protein.html
. The nanoparticle clusters created in the study contain magnetic nanoparticles, gold nanoparticles, and quantum dots, different combinations and arrangements of which produce different physical and optical properties and so fine control of assembly is important; these clusters can be used as MRI contrast media, fluorescence imaging, and drug transport. The DNA and proteins are atomically precise structures and work like this represents promising baby-steps on the path to mature atomically precise manufacturing of materials. 3. Wireless Brain Computer Interfaces.
There have been a number of approaches over the past couple of years to untether brain computer interfaces from the cables typically used to connect brain-connected devices to computers, and so enabled more natural freedom of movement and other experiments. This latest device sits on the head and connects via a small port in the skull to an implanted electrode array that records neuronal network activity https://news.brown.edu/articles/2014/12/sensor
. It’s battery allows WiFi data transmission for up to two days but at 5 cm and 46 grams it still needs another couple of generations of miniaturisation before it might be said to disappear and be genuinely unobtrusive. Demonstration experiments included motor cortex monitoring of monkeys while they walked and general cortical monitoring while monkeys progressed through sleep-wake cycles. 4. Impressive Advances in Solar Cell Technology.
We had a couple of promising solar cell advances this week. First, we had the achievement of a 40% energy efficiency milestone using commercially available solar cells, bandpass filters, and light-concentrating optics http://newsroom.unsw.edu.au/news/science-technology/unsw-researchers-set-world-record-solar-energy-efficiency
. Second, we had yet another advance for spray-on solar cells using colloidal quantum dots and readily available and affordable parts that most people should have access to http://news.engineering.utoronto.ca/new-technique-offers-spray-on-solar-power/
; this is intended to be used in a variety of manufacturing situations with roll-to-roll printing or spraying on firm, curved, or flexible substrates, and ideally will lead to a future ability to directly coat irregular roofs and other surfaces - it will also benefit from independent advances in quantum dot materials development. 5. Cubic Millimeter Computers.
Full computer systems measuring one millimeter cubed have been developed that include wireless communications, computation and data storage, battery, photovoltaic recharging, and sensors such as pressure, temperature, and imaging for image and video capture https://www.youtube.com/watch?v=VjLRNkNgJGU
. The chips are assembled in layers with different sub-components layered on top of each other to form the whole unit. Just think: a tiny wireless camera only a millimeter in size, or a million of them (only a cube of material 10cm on a side) scattered around the environment to provide some impressive (and near invisible) surveillance capabilities. This is smart dust and we can only begin to imagine the applications that may be possible. The group ultimately wish to shrink the complete systems down to the micron-scale where individual units might fit inside cells. 6. Milestone for Tabletop Particle Accelerators.
The most powerful tabletop particle accelerator in the world demonstrated the ability to produce electrons with an energy of 4.25 giga-electronvolts http://newscenter.lbl.gov/2014/12/08/world-record-for-compact-particle-accelerator/
. While the system was hooked up to a much larger petawatt laser system, the laser-plasma accelerator comprising a 9cm long tube was able to induce an acceleration gradient 1,000 times greater than normal particle accelerators. For comparison the monumental LCH produced particle collisions measuring 4 terra-electronvolts and aims to achieve 14 TeV later next year. There are thoughts that such compact laser-plasma devices (or assemblies of them) may be able reach these energy levels in future. 7. Self-Assembled Optical Memory.
A new molecular self-assembly system creates uniform surfaces comprised of precisely ordered arrays of identical, optically-sensitive molecules that switch between two different states http://spectrum.ieee.org/nanoclast/semiconductors/memory/selfassembly-technique-offers-potential-scalable-prodution-of-optical-memory
. Not only are the molecules photochromic, meaning they change colour reversibly when irradiated with light, but they are electric dipoles, which helps with self-assembly and binding onto surfaces while still retaining their attractive optoelectronic properties. The group hope to develop the system into molecular-scale memory storage devices with data densities up to 1,000 times greater than what is possible today. 8. Latest Developments on RoboBrain.
RoboBrain is intended to be a search and knowledge engine for robots, that robots and related devices can query for data and instructions and, importantly, send data back to RoboBrain as they carry out the task in order to help the system learn over time and make it better http://www.technologyreview.com/view/533471/robobrain-the-worlds-first-knowledge-engine-for-robots/
. Given the many differences in robotic architecture this is a difficult problem and a difficult project. Beyond receiving feedback directly from robots themselves, RoboBrain is also designed to allow independent researchers to contribute knowledge to the system with hope being that a community network of developers and researchers will help the system grow quickly and become more broadly useful to more robots in more situations. Demonstrations have involved robots using the system to help navigate indoors or move cooking ingredients around but an important capability will be the application of knowledge learned in one situation to other situations. 9. Graphene Structures Fabricated with Lasers.
A new room-temperature process can fabricate patterned, flexible, multilayered graphene microstructures out of a polymer with a computer-controlled laser http://phys.org/news/2014-12-defects-laser-induced-graphene.html
. The material comprises a complex interconnected foam mesh of graphene flakes, and patterns can comprise discrete supercapacitor designs. The group claim the process is scalable, may eventually result in a roll-to-roll manufacturing process and so far produces functional structures that perform well even after 9,000 charge-discharge cycles. 10. Entropy, Thermodynamics, and Life.
While this article was first presented at the start of the year I only stumbled across it this week thanks to +Samuel Holmes http://www.quantamagazine.org/20140122-a-new-physics-theory-of-life/
. It concerns a recent, and ambitious theory linking entropy, thermodynamics, and the emergence and evolution of life; it is intended to underlie and support evolution via natural selection. Basically, systems with an external input of energy tend to evolve towards increasing their irreversibility, and towards increasing their energy absorption and subsequent dissipation into the local environment. The claim is energy dissipation and entropy increases drive the spark of matter into self-replicating life and the evolution of living systems. An archive of the SciTech Digests can also be found here: http://www.scitechdigest.net