日本是全球老齡化最快的大型經濟體。如今約有30%國民年逾65歲，且獨居長者的人數持續上升。隨著家庭規模縮小、傳統的多世代同住模式逐漸消失，孤立感已成為日本最迫切的社會問題之一。
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2026-03-10 00:00:00:0张 洋3014433310http://paper.people.com.cn/rmrb/pc/content/202603/10/content_30144333.htmlhttp://paper.people.com.cn/rmrb/pad/content/202603/10/content_30144333.html11921 读懂两会关键词“政绩观”（两会笔记）。新收录的资料对此有专业解读
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?”)
Meanwhile, home sellers are hopeful that lower mortgage rates will attract buyers.