SciTech #ScienceSunday Digest – 09/2015.
Permalink here: http://www.scitechdigest.net/2015/03/dna-nanotubes-injected-hydrogels-super.html
DNA nanotubes, Injected hydrogels, Super atomic bonds, Quicker multicore chips, DeepMind plays games, DNA minicircle applications, Optogenetic pain control, Superatom superconductors, 5G at 1Tbps, New agricultural tools.
1. Self-Assembled DNA Nanotubes
Continuing the development and evolution of DNA origami techniques we saw the demonstration of a new method of directed DNA self-assembly to produce DNA nanotubes http://www.mcgill.ca/channels/news/building-tailor-made-dna-nanotubes-step-step-243039. The new method adds modular block subunits iteratively, results in fewer errors, and by incorporating fluorescent tags the group were able to observe the addition of successive blocks to the nanotube. The prototype DNA nanotubes constructed with the technique reached about 20 units, or 450nm in length. I imagine such structures being used as atomically precise scaffolding in future.
2. Drug Delivery via Injected Self-Healing Hydrogel
A new self-healing hydrogel comprised of a mesh of nanoparticles and polymer strands can be implanted into patients simply by injecting through a syringe http://newsoffice.mit.edu/2015/self-healing-nanogel-drug-delivery-0219. Such gels might carry one or more drugs at a time that are released at a controlled rate over a defined period of time; the prototype performed successfully in mice and released both a hydrophobic and hydrophilic drug over several days. I’d also be interested to see if such a gel could be loaded with functional cells – either bacterial or modified versions of the patients own – and protect such cells from the immune system as they respond to the environment and produce useful biochemical factors.
3. Confirmation of Metastable Innershell Molecular States
Metastable Innershell Molecular States were a theoretical prediction of short-lived molecules formed by high-energy collisions and bound together by deep electrons in the inner, as opposed to outer, shell or orbital. Bond strengths for these short-lived molecules are up to 1,000 times stronger and lengths 100 times shorter than normal molecules, and their dissociation would produce high-energy X-rays http://en.wikipedia.org/wiki/Metastable_inner-shell_molecular_state. New work seems to confirm that these entities do in fact exist http://nextbigfuture.com/2015/02/confirmation-of-ultra-high-energy.html. Possible future applications include high intensity X-rays, advanced lithography, superexplosives, and inertial fusion.
4. Boosting the Speed of Muticore Chips
A new scheduling technique distributes data and computation throughout multicore chips with such efficiency that a test 64 core chip realised a computational speed increase of 46% and a power consumption decrease of 36% https://gigaom.com/2015/02/20/mit-researchers-claim-they-have-a-way-to-make-faster-chips/. The advance addresses problems in communication and memory access in increasingly parallel systems by trying to co-locate data and the associated computation. That’s a pretty decent contribution; one piece of work from one team produces the equivalent of an additional full year of Moore’s Law type increases.
5. Google DeepMind Learns to Play Many More Games
Originally demonstrating the ability to independently learn to play and master a couple of very simple computer games, the team behind Google-acquired DeepMind has successfully developed the system further to the point where it has now taught itself to play and master a much wider range of more complex 1980s Atari games http://spectrum.ieee.org/tech-talk/robotics/artificial-intelligence/google-ai-learns-classic-arcade-games-from-scratch-would-probably-beat-you-at-them. The system, known as a deep Q-network, the result of the evolution of deep learning techniques, and running on a single GPU-equipped desktop computer achieved impressive results in the games. The team next hope to address requirements for sophisticated exploration and long-term planning, and plan to move onto games from the 1990s.
6. Cancer Detection and Cell Manipulation with DNA Minicircles
DNA minicircles (http://en.wikipedia.org/wiki/Minicircle) are short plasmid derivatives about 4,000 basepairs long able to function as transgenic elements to get DNA inside cells, but lack bacterial DNA and so less likely to be recognised as foreign, and can also be made to replicate or not (and degrade) in the host cell. By injecting into mice DNA minicircles (in a carrier), that encode a gene only active during embryonic development, and controlled by a promoter region that is only active during embryonic development and in most (all?) cancer cells (never in healthy adult cells), researchers have caused mice with cancer (but not those without) to express a protein that can be easily detected in blood within two days to diagnose the presence and approximate amount of cancer http://med.stanford.edu/news/all-news/2015/02/customized-dna-rings-aid-early-cancer-detection-in-mice.html. Other applications include producing fluorescent proteins to image cancer cells directly, using different elements able to respond & manipulate different cells behaviour in different ways, and ideally via oral delivery.
7. Controlling Pain via Optogenetics
By shining specific wavelengths of light onto the anterior cingulate cortex of mice brains modified by optogenetics (certain neurons producing light-sensitive channel proteins) researchers were able to controllably stimulate inhibitory neurons to drastically reduce the experience of pain for the mice http://www.uta.edu/news/releases/2015/02/mohanty-pain-inhibition.php. This was far more effective than electrode-based stimulation, which leads to activation of both inhibitory and excitatory neurons involved in these circuits. The group has also built up considerable expertise in near-infrared two-photon stimulation to allow deeper and more precise targeting and activation of optogenetically modified neurons.
8. Superconductivity in Superatoms
Superatoms (http://en.wikipedia.org/wiki/Superatom) made of a homogenous cluster of aluminium have been found to form cooper-pairs and superconduct at a temperature of 100 Kelvin http://news.usc.edu/76293/these-superconductors-are-just-getting-warmed-up/. Contrast this to bulk aluminium, which superconducts at 1 Kelvin. Another impressive feat demonstrated by the group was the ability to construct superatoms with a defined number of atoms, from 32 all the way up to 95 atoms and to precisely probe the electron energy levels of each. The hope is that further research on other types of elemental superatoms might reveal far higher superconducting temperatures, always striving for room temperature, and fabricating tracks of connected superatoms on circuits might enable nanoscale superconducting paths for a range of applications. See also superatom crystals http://www.rsc.org/chemistryworld/2013/06/artificial-superatoms-new-periodic-table.
9. 5G Cellphone Speeds of 1 Terabit per Second
New prototype wireless transmitters and receivers were demonstrated for future 5G networks that successfully facilitated data transfers of 1 terabit per second over a distance of 100m http://nextbigfuture.com/2015/02/5g-cellphone-wireless-speeds-of-1.html. The group ultimately hope to bring the end-to-end latency of the system down below one millisecond. This compared to Ofcom, which hopes to have 5G networks offering 50 Gpbs across the UK by 2020.
10. A Trio of Agricultural Developments
There were a few interesting agricultural projects this week. First, vertical farming continues to spring up around the world with a new facility next to a Wyoming parking lot called Vertical Harvest able to produce 37,000 pounds of greens, 4,400 pounds of herbs, and 44,000 pounds of tomatoes http://www.theverge.com/2015/2/26/8112889/vertical-farm-wyoming-hydroponics-grow-food. Second, we saw a new beehive design called the Flow Hive demonstrated that automatically extracts honey via tap without disturbing the bees http://www.thisiscolossal.com/2015/02/honey-on-tap/. Finally, new company Afforestt offers a new system for regrowing forests that can produce a mature forest in just ten years http://nextbigfuture.com/2015/02/growing-mature-forest-in-ten-years.html.
Archived: http://www.scitechdigest.net/2015/03/dna-nanotubes-injected-hydrogels-super.html
