Protein building blocks for nanosystems

The Freiburg researchers Dr. Andreas Schreiber and Dr. Matthias Huber, the head of their research group Dr. Stefan Schiller, and their colleagues at the University of Constance have developed the concept of protein adaptor based nano-object assembly (PABNOA). PABNOA makes it possible to assemble gold nanoparticles in various structures with the help of ring-shaped proteins while defining the precise distance between these particles. This opens up the possibility of producing bio-based materials with new optical and plasmonic properties. The field of nanoplasmonics focuses on miniscule electromagnetic waves metal particles emit when they interact with light. The principle behind the production of these materials could also be applied to develop nanosystems that convert light into electrical energy as well as bio-based materials with new magnetic properties. The team published its findings in the journal ("Molecular protein adaptor with genetically encoded interaction sites guiding the hierarchical assembly of plasmonically active nanoparticle architectures"). defined architectures consisting of proteins (green in the model) and gold nanoparticles The schematic models and electron microscope images show defined architectures consisting of proteins (green in the model) and gold nanoparticles. (Image: Stefan Schiller) Schiller's team is using tailor-made proteins as building blocks to assemble nanosystems with new physical, chemical, and biological properties. The sustainable and resource-conserving production of these proteins occurs in processes like the natural energy and material cycle of cells. To this end, the team is working on equipping bacteria with additional elements - such as enzymes, transporters, switches, and organelles, the organs of the cell. In the future, the scientists hope that these elements will extend the range of functions of the cell to enable the sustainable production of the desired nanosystems with a minimum of resources. The same principle could also be used to produce basic raw materials for the chemical industry. "Methods like this are indispensable for the successful transition of our economy to a sustainable and resilient bioeconomy," says Schiller. Stefan Schiller is a research group head at the Freiburg Center for Systems Biology (ZBSA) and a member of the Cluster of Excellence BIOSS Biological Signalling Studies of the University of Freiburg. The research was conducted in cooperation with scientists from the University of Constance. The project is receiving funding from the Baden-Württemberg Foundation within the context of the research network "Functional Nanostructures."
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A 'pin ball machine' for atoms and photons

Ultracold atoms in the so-called optical lattices, that are generated by crosswise superposition of laser beams, have been proven to be one of the most promising tools for simulating and understanding the behaviour of many-body systems such as solid crystals – for example with respect to their electric or magnetic properties. However, the implementation in free space has some limitations such as the distance between the atoms (around 400 nm) and the short range of the interactions. Now a team of theorists around Prof. Ignacio Cirac (MPQ, Garching) and Prof. Jeff Kimble (California Institute of Technology, Pasadena, USA) suggests a new set-up that integrates the advantages of ultracold atomic physics and nano-photonics to circumvent these limitations predicting lattice constants about ten times smaller than in a free space optical lattices and the possibility to mediate longer range interactions (, "Subwavelength vacuum lattices and atom-atom interactions in photonic crystals"). Illustration of the dielectric nano-photonic lattice for trapping atoms and making them interact Illustration of the dielectric nano-photonic lattice for trapping atoms and making them interact. (Graphic: MPQ, Theory Division) The authors use the opportunities provided by nano-engineered dielectrics, the so-called Photonic Crystals, to study both how to trap the atoms closer to each other and make them interact through the guided modes in the structure. As a consequence, the energy scales of the system are increased as well as the range of the interactions, being able to explore new forms of quantum many-body matter. The basic idea is to take a thin dielectric slab the refractive index of which gets periodically modulated by either drilling holes or installing little cylindrical posts in a grid-wise pattern. By using a combination between optical and vacuum forces, the authors show how to make lattices with up to 50 nm, around ten times smaller than for optical lattices. “With these subwavelength lattices we can investigate about the same quantum many-body phenomena as in free space optical lattices,” explains Dr. Alejandro González-Tudela, a scientist in the Theory Division of Prof. Cirac and first author of the publication. “But the difference and advantage of our proposed scheme is that the atoms are much closer to each other. That way we achieve higher tunneling rates and interaction energies for simulations of quantum many-body systems. And this implies that we can relax the cooling requirements of the atoms.” But it is not only the smaller scale of the lattice which provides the possibility to do new kinds of physics. The geometry of the two-dimensional thin dielectric layer allows trapping and guiding the light that falls onto the slab. So an incoming photon interacts strongly with an atom, and then it bounces off. But it does not fly into space: the photon propagates through the waveguide and finds another atom to interact with, and then it goes to the next one and interacts. “Our analysis show that we should be able to achieve atom-atom-interactions, where the interaction mechanism is not by atom hopping (as in free space optical lattices) but by exchange of photons”, Alejandro González-Tudela says. “The result is a two-dimensional solid where the atoms are held together and talk to each other not by phonons – as in regular matter – but by photons. This implies a qualitatively new domain for light-matter interactions, with the capability to ‘design’ the strength and the range of the interactions. We would gain access to a rich set of phenomena, including, for example, quantum magnetism or spin-spin-interactions mediated by photons.
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Crowdfunding could be a simple way to pay for science research

The outcome of science research benefits us all, but knowledge doesn’t come cheap. Crowdfunding – promoted by government incentives – may be the best way to meet these costs and garner greater awareness of scientific research priorities. There is an ongoing debate on how to measure the amount of knowledge created through research. The traditional approach is to look at the number of published articles in peer-reviewed journals and work out the impact they have. How much does it cost to produce knowledge? In 2012, the worldwide expenditure on scientific research and development was US$1.5 trillion, while an estimated 1.9m peer reviewed articles were published that year ("An overview of scientific and scholarly journal publishing", pdf). This works out as a whopping US$790,000 per article. This is a very rough and exaggerated estimate, since not all commercially funded research is published – and some research projects like space missions are extremely costly. Also, this estimate does not account for patents. But it’s an indication of how expensive science is and shows that there’s a market for it. Can we call this a market? I believe so. The average price of a car in the US in 2012 was US$30,000 and more than 10m were sold – this looks relatively cheap compared to the price of a peer-reviewed article. Value for money So do we get value for money when it comes to knowledge? The likely answer is No, because in most of cases the scientific research market is an “oligopsony” –- a market with many producers (the scientists and research groups) but only a few or even just one formal consumer. Society is the consumer, but the money to fund research is channelled through at most, a handful of funding agencies (often a single agency). This has the benefit of ensuring that money is divided up fairly between disciplines – but on the other hand, funding agencies may exercise their market power to actually spend as little as possible. Why? Because there’s no one else to offer a better deal to the scientists. Crowdfunding has proven to be a good source of investment for many small projects and start-up companies as it allows the easy aggregation of small contributions from many individuals to reach a target. As science becomes more mainstream – who hasn’t heard of the Higg’s Boson? – the myth that science is weird and alien is being overturned. This means there’s more fertile ground in which to secure scientific funding through collective effort. There are now many websites dedicated to scientific crowdfunding such as including Petridish.org, Experiment.com, and crowdfunding has successfully funded several projects – for example the first publicly accessible orbital space telescope, and a specialist pressurised flight suit. These are good models but the real funding vehicle is yet to come, after all these projects have budgets under US$10,000 on average and this sort of cash doesn’t go far in terms of science. flight suit crowdfunding Crowdfunding has paid to carry new inventions to the heavens, like this flight suit. (Image: Final Frontier Designs/Kickstarter) With a little government help Clearly, this is where governments have to step in. Many countries have already benefited from governments having acted to remove monopolies and deregulate controlled industries in various markets. For example, air travel deregulation led to the boom in low-cost flights, while deregulating telecoms has seen a growth in services and providers. In order for crowdfunding to actually involve the crowd, a government has to provide an incentive for funders, in this case its citizens. A great way would be to introduce science-funding shares – a sort of bond that could be issued by any research group for funding a specific research project, which could be tax deductible as an incentive. Of course, not all funding should be given to the crowd, but at least a portion of funding could be distributed in this way, with proper regulations and control. There’s been a lot written about how crowdfunding can improve research outreach, and the extent to which the public understand research projects' aims and motivations. But large-scale involvement of citizens also poses some interesting questions. For instance, there is little doubt that a country needs strong and well-equipped armed forces. But would the research and development of nuclear weapons be ever sanctioned for crowdfunding by the public? Probably not. The world is growing more competitive – and science is taking on a more important role in today’s society. In order for countries to remain competitive, new approaches to stimulate growth have to be developed. In the many countries with dysfunctional central governments, crowdfunding could be the only way for citizens to impose their democratic choices. The internet has radically changed most forms of communication, government and business – why not science and research funding too?
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