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Open and even scientifically contentious debates about policy issues are, on balance, beneficial. In that context, recent signals from Europe are encouraging, whereas those from the US Congress are dispiriting.
Add some noise, and many dynamic systems respond to weak signals more strongly. Some sort of threshold process was thought to be necessary for this effect, but a new model removes the restriction.
Many structural features of the mammalian central nervous system can be explained by a morphogenetic mechanism that involves mechanical tension along axons, dendrites and glial processes. In the cerebral cortex, for example, tension along axons in the white matter can explain how and why the cortex folds in a characteristic species-specific pattern. In the cerebellum, tension along parallel fibres can explain why the cortex is highly elongated but folded like an accordion. By keeping the aggregate length of axonal and dendritic wiring low, tension should contribute to the compactness of neural circuitry throughout the adult brain.
This product update shows its new style but maintains its old function of providing information on products, such as a video tape analysis system, new autofluorescent proteins, and a microplate and reagent handling system.
