If a charged beam traverses a plasma, it will quickly redistribute the plasma's electrons, thereby reducing the net Coulomb force while leaving the magnetic force unaffected. The result is a magnetically pinched beam. Within the past year, two experiments at SLAC have demonstrated the effect. By contrast, the E-150 experiment was intended to explicitly examine plasma focusing, independent of the sign of the beam's charge. According to Baldis, the focusing region of the next generation of linear colliders could be reduced in length from kilometers to meters by using the plasma-focusing approach.
Neural noise can help regulate human blood pressure.
In common with other living organisms, the human body operates with unavoidable electrical noise, analogous to radio static, in its nervous system. A new experiment, performed by researchers in Japan, provides evidence that the body can exploit this noise to aid the transmission of weak signals in the nervous system. Such signal enhancement using noise is called stochastic resonance. By tilting a subject back and forth on a horizontal table, the researchers moved blood to and from the lower part of the body. Blood draining from the chest area stimulated a weak repeating signal in the body, which the brain interpreted as a drop in venous blood pressure.