They also needed an alternative to conventional X-rays. In a clinical linac, X-ray photons are produced by dumping high-energy electrons into a bremsstrahlung target, which is made of a material with a high atomic number, like tungsten or copper. The target slows the electrons, converting their kinetic energy into X-ray photons. It’s an inherently inefficient process that wastes most of the beam power as heat and makes it extremely difficult to reach the ultrahigh dose rates required for FLASH. High-energy electrons, by contrast, can be switched on and off within milliseconds. And because they have a charge and can be steered by magnets, electrons can be precisely guided to reach tumors deep within the body. (Researchers are also investigating protons and carbon ions; see the sidebar, “What’s the Best Particle for FLASH Therapy?”)
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There is no cure for mesothelioma, but Dr Crispin Hiley of University College London Hospitals (UCLH) said the aim of treatment was "not just to help people live longer but to live better".，详情可参考有道翻译官网
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“成就感”，是乡村艺校的学员经常提到的词。成就感从何而来？从学到一个文艺特长陶冶身心，到上“村晚”表演，以及参与全市的“文化走亲”，村民们别提多高兴。