The best of the rest from the physics arXiv this week:
Frequency Spectrum of the Casimir force: Interpretation and a Paradox
Three-Dimensional Metamaterials with an Ultra-High Effective Refractive Index over Broad Bandwidth
Afterglows of Gamma-Ray Bursts: Short vs. Long GRBs
The Secret World of Shrimps: Polarisation Vision at its Best
How Occasional Backstepping can Speed up a Processive Motor Protein
Even the vacuum has an pronounced complex metamaterial behavior due its foamy structure given by multinomial distribution of density fluctuations (note that some metamaterials are made of foam). We can observer it during the autofocusation of light at long distances, where even the most distant stars appear as pin-point objects and no dispersion of light occurs in broad range of wavelength, while the solid state metamaterials are working in narrow range of wavelengths.
We can explain this behavior by self-tunable behavior of quantum foam forming the vacuum. This foam gets more dense under shaking by the same way, like soap foam. It means, the light spreads always through portion of foam bubbles, whose size remains perfectly tuned for given wavelength and energy density. This is the consequence of criticality in phase transition of quantum foam in its present state, as explained herein http://arxivblog.com/?p=352 .
We can consider, such criticality has partly an anthropocentric origin. The the system of random density fluctuations forming the quantum chaos of vacuum enables the infinite ways, how to see through it. But we are sampling it selectively by such way, which enables us to see through it at the maximal distance. This sampling in turn determines the physical laws, which we assigning the observable reality by such way.
The polarization vision is surprisingly widespread in world of insect. For example the bees can determine the concentration of sugar in nectar by such way and the aphids can determine the thickness of the cellulose epidermis, covering the plants surface, so they don’t waste a time by needling of phloem cortex on wrong places. It’s well known, the locusts are avoiding a large water areas, which are serving as a light polarizers, so that the sheets of glass can be used to prohibit them in landing and crops destruction.
Some animations of kinesin structure walking collected from different source.
http://superstruny.aspweb.cz/images/chemistry/biochem/sval1.avi
http://superstruny.aspweb.cz/images/chemistry/biochem/sval2.avi
http://superstruny.aspweb.cz/images/chemistry/biochem/kinesin_walk.avi
http://superstruny.aspweb.cz/images/chemistry/biochem/myosin_v_em_animation.gif
http://superstruny.aspweb.cz/images/chemistry/biochem/pre_stroke_myo_v.gif
http://superstruny.aspweb.cz/images/chemistry/biochem/post_stroke_myo_v.gif