Word: positrons
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...three basic particles of antimatter—positron, antiproton and antineutron—share the same masses and magnitudes of charge as those of their counterparts in matter—electron, proton and neutron, but with opposite charges. Just as a proton and electron compose a hydrogen atom, an antiproton and positron make an antihydrogen atom. When matter and antimatter particles collide, they destroy each other in a burst of energy...
First, Gabrielse used lasers to excite the electron in a cesium atom into a higher orbit. When the cesium atom collides with a positron, the electron binds with the positron, to create an atom that is half matter and half antimatter. When that atom collides with an antiproton, the positron binds to the antiproton, forming an antihydrogen atom...
BRAIN IMAGING Finally, scientists at the University of Pittsburgh announced that they had successfully developed a procedure that allows them to peer into the brains of Alzheimer's patients with positron emission tomography (PET) scans to see telltale plaque deposits. Before now, doctors could not track the progress of these plaques until after the patient died, when the brain could be autopsied. Using the new technique, doctors may be able to begin treatment long before the first symptoms appear...
...million older Americans will be affected by the progressive brain disease, 3 million more than previous projections. Although the illness is still definitively diagnosed only at autopsy, advances are being made in finding it earlier. Doctors can improve the accuracy of detection 30% by combining various cognitive tests with positron-emission tomography (PET). PET is an imaging technique that shows the brain's metabolism at work. Preliminary research suggests that it may also be possible for physicians to detect certain telltale signs of Alzheimer's disease--the so-called amyloid and tau proteins--in the spinal fluid...
...weeks before, on Sep. 18, a competing group, called ATHENA, which also uses the accelerator at CERN, announced that they had succeeded in joining an antiproton and a positron. This group is composed of mainly European scientists, who had not been serious competition for the Harvard group before...