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A new type of structure for converting red light into blue has been unveiled by researchers in the US. Known as frequency doubling or second-harmonic generation (SHG), the conversion involves "nanocups", which are tiny, artificially designed 3D structures. SHG is used in light sources and in metrology applications - and the researchers believe that the new structures could be adapted to achieve frequency doubling in parts of the electromagnetic spectrum where it is currently not possible.

Whether it is the frothy milk on your cappuccino, the soapy suds in your bath or the large-scale structure of the universe, foams have intrigued physicists for many years. Now, for the first time in a lab, an international group of scientists has made the Weaire-Phelan foam - which physicists believe is the lowest-energy structure for a foam formed of equal-volume bubbles.

Does this mean that there is foam that is non regular that can have even less energy structure? "which physicists believe is the lowest-energy structure for a foam formed of equal-volume bubbles."

Some interesting ideas for our crowdsourcing game in here.

it seems that there are indications that we are differently wired .... Sex differences in human behavior show adaptive complementarity: Males have better motor and spatial abilities, whereas females have superior memory and social cognition skills. Studies also show sex differences in human brains but do not explain this complementarity. In this work, we modeled the structural connectome using diffusion tensor imaging in a sample of 949 youths (aged 8-22 y, 428 males and 521 females) and discovered unique sex differences in brain connectivity during the course of development. Connection-wise statistical analysis, as well as analysis of regional and global network measures, presented a comprehensive description of network characteristics. In all supratentorial regions, males had greater within-hemispheric connectivity, as well as enhanced modularity and transitivity, whereas between-hemispheric connectivity and cross-module participation predominated in females. However, this effect was reversed in the cerebellar connections. Analysis of these changes developmentally demonstrated differences in trajectory between males and females mainly in adolescence and in adulthood. Overall, the results suggest that male brains are structured to facilitate connectivity between perception and coordinated action, whereas female brains are designed to facilitate communication between analytical and intuitive processing modes.

I like this abstract: sex, sex, sex, sex, SEX, SEX, SEX, SEX...!!! I wonder if the "sex differences" are related to gender-specific differences...

What happens if you strap NSGA-II to optimize the usage of your abstract data structures?

With self-assembly guiding the steps and synchronization providing the rhythm, a new class of materials forms dynamic, moving structures in an intricate dance. Researchers have demonstrated tiny spheres that synchronize their movements as they self-assemble into a spinning microtube.

This is quite similar to the following paper. Here they show how tiny variations of particle parameters can produce clearly distinct structures: Thermal and Athermal Swarms of Self-Propelled Particles --> http://arxiv.org/abs/1201.0180

some biomimicry used in energy systems... maybe it sparks some ideas

not much new that has not been shared here before ... BUT: we have done relativley little on any of them. for good reasons?? don't know - maybe time to look into some of these again more closely Energy Efficiency( Termite mounds inspired regulated airflow for temperature control of large structures, preventing wasteful air conditioning and saving 10% energy.[1] Whale fins shapes informed the design of new-age wind turbine blades, with bumps/tubercles reducing drag by 30% and boosting power by 20%.[2][3][4] Stingray motion has motivated studies on this type of low-effort flapping glide, which takes advantage of the leading edge vortex, for new-age underwater robots and submarines.[5][6] Studies of microstructures found on shark skin that decrease drag and prevent accumulation of algae, barnacles, and mussels attached to their body have led to "anti-biofouling" technologies meant to address the 15% of marine vessel fuel use due to drag.[7][8][9][10] Energy Generation( Passive heliotropism exhibited by sunflowers has inspired research on a liquid crystalline elastomer and carbon nanotube system that improves the efficiency of solar panels by 10%, without using GPS and active repositioning panels to track the sun.[11][12][13] Mimicking the fluid dynamics principles utilized by schools of fish could help to optimize the arrangement of individual wind turbines in wind farms.[14] The nanoscale anti-reflection structures found on certain butterfly wings has led to a model to effectively harness solar energy.[15][16][17] Energy Storage( Inspired by the sunlight-to-energy conversion in plants, researchers are utilizing a protein in spinach to create a sort of photovoltaic cell that generates hydrogen from water (i.e. hydrogen fuel cell).[18][19] Utilizing a property of genetically-engineered viruses, specifically their ability to recognize and bind to certain materials (carbon nanotubes in this case), researchers have developed virus-based "scaffolds" that

Nice application of swarm robotics for building various structures. See the video at: http://www.youtube.com/watch?v=LFwk303p0zY Their compilation process of a desired structure into local behavior rules seems of most interest.

Several recent papers on biomimetics and photonics, including works on structural colours, radiation shielding, spiders and more.

including one for Tom: Structural color and its interaction with other color-producing elements: perspectives from spiders Bor-Kai Hsiung ; Todd A. Blackledge ; Matthew D. Shawkey [+] Author Affiliations Proc. SPIE 9187, The Nature of Light: Light in Nature V, 91870B (September 8, 2014); doi:10.1117/12.2060831

FEM modelling of bone structures in woodpeckers combined with high speed video of pecking motion etc headgear? shock absorbing structures? low mass hammering penetrators? Lizhen Wang1,2, Jason Tak-Man Cheung3, Fang Pu1, Deyu Li1, Ming Zhang2*, Yubo Fan1* 1 Key Laboratory for Biomechanics and Mechanobiology of Ministry of Education, School of Biological Science and Medical Engineering, Beihang University, Beijing, People's Republic of China, 2 Department of Health Technology and Informatics, the Hong Kong Polytechnic University, Hong Kong, 3 Li Ning Sports Science Research Center, Beijing, People's Republic of China Head injury is a leading cause of morbidity and death in both industrialized and developing countries.

At SRI International in Silicon Valley, researchers have developed perhaps the most impressive microbot army yet: the MicroFactory. It's an ant colony made robotic, with half-millimeter machines zipping around to construct truly impressive structures.

"The metamaterial aperature is only 40 centimeters long and it doesn't move. It's a circuit-board-like structure consisting of two copper plates separated by a piece of plastic. One of the plates is etched with repeating boxy structures, units about 2 millimeters long that permit different lengths of microwaves to pass through. Scanning the scene at various microwave frequencies allows the computer to capture all the information necessary to reproduce a scene."

where is Luzi's comment when one needs it ???

"Her goal was to design and synthesise a super capacitor with increased energy density while maintaining power density and long cycle life. She designed, synthesised and characterised a novel core-shell nanorod electrode with hydrogemated TiO2(H-TiO2) core and polyaniline shell. H-TiO2 acts as the double layer electrostatic core. Good conductivity of H-TiO2 combined with the high pseudo capacitance of polyaniline results in significantly higher overall capacitance and energy density while retaining good power density and cycle life. This new electrode was fabricated into a flexible solid-state device to light an LED to test it in a practical application. Khare then evaluated the structural and electrochemical properties of the new electrode. It demonstrated high capacitance of 203.3 mF/cm2 (238.5 F/g) compared to the next best alternative super capacitor in previous research of 80 F/g, due to the design of the core-shell structure. This resulted in excellent energy density of 20.1 Wh/kg, comparable to batteries, while maintaining a high power density of 20540 W/kg. It also demonstrated a much higher cycle life compared to batteries, with a low 32.5% capacitance loss over 10,000 cycles at a high scan rate of 200 mV/s."

The Robobee takes off without guide wires! It is still powered via a wire, and the control is done with the help of a VICON system and on an external computer, but this still is an amazing feat!

The way they make this thing is just as impressive. The manufacturing technique is "pop-up book" folding, a method that has been developed by the same group and that allows a two dimensional monolithic MEMS structures to be easily assembled into a 3D structure. I actually put this as an item of the "Technology List 2020" on the wiki this morning.

I agree, manufacturing is the amazing thing here ..... as soon as the power-consumption/density problem is solved these things will really take off :)

good luck with this....

In 1996 Sokal hoaxed sociologists with his famous nonsense text on political implications of quantum gravity. Can one play a similar game with "researchers" on Boltzmann brains, multiverses, string landscapes or similar? I doubt, this is just reality satire that can't be topped.

Poor Boltzmann ...