Did you miss this week’s science news? Have no fear, Mark Bruce summarizes some of the findings that caught his eye. Thanks, Mark Bruce!
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SciTech #ScienceSunday Digest 35 – 13th Oct 2013.
Microfluidic assembly, reducing designs to Lego, neuro-processors, carbyne, bacterial cages, stem cell factories, rescuing brain cells.
1. Directed Self-Assembly of Functional Materials in Microfluidics.
Directing two different liquids (acid and peptide solutions) towards each other into a connecting chamber from opposing channels on a microfluidic chip causes a precise interface to form along the length of the chamber. A new technique allows peptides to come out of solution and form a large oligopeptide structure (I’m guessing polymers might also work) along this interface http://phys.org/news/2013-10-microfluidic-approach-functional-materials.html. This is innocuous but extremely powerful – and a potentially transformative tool. You can picture this structure as a membrane along the interface. They also demonstrated two parallel “membranes” side-by-side in the chamber. Maybe many more parallel membranes would be possible. Assuming an appropriate membrane material is used I think these structures could be embedded with enzymes and other functional channels to conduct novel and controlled chemistry e.g. add DNA to one channel and the RNA polymerase on the first membrane reads the DNA to produce mRNA on the other side, which is taken up by the Ribosomes embedded on the second membrane to produce the corresponding protein on the other side, etc.
2. Automatically Reducing Any 3D Design to Lego + Instructions.
Another seemingly innocuous but incredibly powerful tool. New software allows you to load a file specifying any 3D shape of interest and have it automatically converted into an optimal design and construction instructions for building the 3D object out of Lego bricks http://actu.epfl.ch/news/software-to-construct-everything-with-legos/ – complete with colour coding and different sized bricks to optimise strength and stability. This is apparently something that LEGO has been trying to solve for a long time. The video is worth a watch Un logiciel pour tout construire en Lego. This is powerful not because of its use in designing Lego structures, but rather as platform for generalising to other “bricks” such as those used in DNA Origami e.g. self-assembled fabrication of useful complex 3-dimensional molecular structures.
3. Qualcomm to Commercialise Neuromorphic Chips.
As a result of years of investment into and acquisitions of research into hardware and algorithms that mimic the underlying function of circuits in the human brain, Qualcomm is set to build new chips with novel architectures – Neural Processing Units – for partners including companies and researchers from next year http://www.technologyreview.com/news/520211/qualcomm-to-build-neuro-inspired-chips/. The chips use physical structures, parallel and distributed, derived from real neurons but the true innovation is the ability they now have to fabricate large numbers of these structures in silicon. Machines that utilise the chips are expected to perform complex tasks while consuming little power; some of these tasks will include things like artificial vision sensors, robot controllers, and brain implants. In related news we had better robot vision from MIT http://web.mit.edu/press/2013/better-robot-vision.html.
4. Carbyne: The Strongest Material Ever Conceived.
New simulations / calculations indicate that carbyne, a material that comprises one-dimensional chains of carbon atoms joined by double (or triple followed by single) carbon bonds, would be the strongest material ever http://news.rice.edu/2013/10/09/carbons-new-champion/. Carbyne’s would have double the tensile strength of graphene, three times the stiffness of diamond, could be stretched to alter it’s bandgap, twisted to make a magnetic semiconductor, and be completely stable at room temperature. Only drawback is that there is at the moment no controllable synthesis process; carbyne has only be observed in compressed graphite, interstellar dust, and created in minute quantities by chemists.
5. Microscopic 3D Printed Cages for Bacterial Confinement.
Laser-light focused onto a photoreactive gelatin solution containing bacteria allows arbitrarily complex 3-dimensional structures to be built up to encage and entrap the bacteria http://www.eurekalert.org/pub_releases/2013-10/uota-3pm100413.php. The resulting porous material is biocompatible and very bio-friendly in the sense that it is porous enough to allow nutrients to diffuse in, wastes to diffuse out, and signalling molecules to transfer back and forth. Applications: (i) colonies of bacteria can be studied in a controlled environment, (ii) multi-shelled structures of one bacterial species next to / surrounded by another (but separated by a polymer wall) can allow signalling studies, (iii) surplus material can be removed to isolate just the containers to allow for easy and convenient transportation. Simple, elegant, and very powerful. Could they be further modified to be used as implantable bioreactors to provide power to cybernetic implants? In related 3D printing news ink with silver nanoparticles has been used to print complex computer circuits on paper substrates http://www.newscientist.com/article/mg22029374.500-print-a-working-paper-computer-on-an-80-inkjet.html#.UlpQ2lDikvQ that enabled a printed humidity sensor and WiFi antenna to be connected via conductive tape to other components.
6. Stem Cell Drug Factories and Organ Regeneration.
Mesenchymal stem cells are being used as programmable targeted drug producing agents http://www.hsci.harvard.edu/newsroom/stem-cells-engineered-become-targeted-drug-factories. In this proof-of-concept particular mRNAs inserted into the cells caused the cells to produce both adhesive proteins and the anti-inflammatory molecule interleukin-10; when injected into a mouse’ bloodstream the cells targeted and stuck to sites of inflammation and successfully reduced swelling by secreting the compound. An interesting platform to develop further. In related news a simple infusion of epithelial blood vessel cells (derived from stem cells) results in the cells taking up residence in blood vessels, responding to tissue and organ-specific signals, and becoming indistinguishable from native epithelial cells https://www.fightaging.org/archives/2013/10/towards-the-use-of-blood-vessel-cells-to-repair-and-regenerate-organs.php – possible rejuvenation and tissue repair applications. Stem cells are also being made in clinically-relevant quantities for the first time http://www.cam.ac.uk/research/news/stem-cell-breakthrough-could-set-up-future-transplant-therapies.
7. Membranes and Silicon Compatible with Graphene.
Dip-pen Nanolithography has been used for the first time to write biological phospholipid membranes across sheets of graphene http://phys.org/news/2013-10-artificial-cell-membranes-graphene.html. These model membranes will not only be useful for studying but may also have applications in biological sensing, catalysis, and drug delivery for example by embedded the controlled membrane with enzymes and other proteins. For the first time graphene has also been shown to retain its amazing properties when coated with a layer, or film, of silicon http://phys.org/news/2013-10-major-graphene-solar-cells-retains.html, which if perfected could have great uses in photovoltaics or computing. There’s actually a huge amount of work going into graphene solar cells http://www.nanowerk.com/spotlight/spotid=32691.php, and a roll-to-roll graphene production process shows promise http://spectrum.ieee.org/nanoclast/semiconductors/nanotechnology/high-quality-graphene-could-be-produced-in-bulk.
8. Halting the Death of Brain Cells.
A new drug has been used to halt the death of brain cells (in mice) for the first time http://www.independent.co.uk/news/uk/home-news/alzheimers-treatment-breakthrough-british-scientists-pave-way-for-simple-pill-to-cure-disease-8869716.html. The drug blocks faulty signalling in brains affected by neurodegenerative diseases and when tested in mice with comparable diseases successfully stopped the on-going death of neurons that the animals had been suffering from; normal behaviour was restored. The drug is not only orally administered but also crosses the blood-brain barrier. Some minor side-effects were noticed but the work paves the way for developing even better compounds to help people in future.
9. Simulating then Testing a Superconductor.
A superconducting material simulated and designed on a computer has been synthesised and tested for the first time http://www.eurekalert.org/pub_releases/2013-10/bu-bpc100813.php. The successful reduction to practice proved that the material did indeed possess all of the properties predicted by the design simulations. The approach involves the use of evolutionary / genetic algorithms that seek to optimise the simulated parameters of the material and in particular its crystal stability. It is hoped that further evolutionary simulations produce even better superconductor materials.
10. Mapping Proteins with Cryoelectron Microscopy.
Single-particle cryoelectron microscopy used to be a poor choice for protein mapping applications, trailing x-ray crystallography and nuclear magnetic resonance, until major improvements in imaging sensors http://newscenter.lbl.gov/feature-stories/2013/09/19/cryo-em/. On-going Moore’s Law style improvements to CCD image sensors, capable of capturing high resolution images from the technique (e.g. 4.5 angstrom resolution of a ribosome), make it a much more viable and attractive alternative for mapping and determining protein structures. The improvements are described as “huge and sudden.”
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