We report the phenomenon whereby the electron spin resonance signal of human nails intensify after irradiation. Forty nail samples from three donors were divided into three groups (X-ray irradiated, γ-ray irradiated, and control). The extent of signal intensified after irradiation was proportional to the given dose under 11% humidity at 20 °C. This result seemed to contradict previous studies, reporting signal fading. Based on literature and our experimental results, we constructed a model taking both the decay and increase into consideration. Our investigation revealed that rapid deterioration in the signal intensity obscured the increase at humidity levels exceeding 40%.

中文翻译：

---

人体指甲的电子自旋共振信号：照射后增加

我们报告了辐射后人体指甲的电子自旋共振信号增强的现象。来自三位捐献者的四十个指甲样本被分为三组（X 射线照射、γ 射线照射和对照）。辐照后信号增强的程度与 11% 湿度和 20°C 下的给定剂量成正比。这个结果似乎与之前的研究相矛盾，报告信号衰落。基于文献和我们的实验结果，我们构建了一个同时考虑衰减和增加的模型。我们的调查显示，信号强度的快速恶化掩盖了湿度水平超过 40% 时的增加。