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The isomer depletion of ^{93m}Mo was recently reported [Chiara et al., Nature (London) 554, 216 (2018)NATUAS0028-083610.1038/nature25483] as the first direct observation of nuclear excitation by electron capture (NEEC). However, the measured excitation probability of 1.0(3)% is far beyond the theoretical expectation. In order to understand the inconsistency between theory and experiment, we produce the ^{93m}Mo nuclei using the ^{12}C(^{86}Kr,5n) reaction at a beam energy of 559 MeV and transport the reaction residues to a detection station far away from the target area employing a secondary beam line. The isomer depletion is expected to occur during the slowdown process of the ions in the stopping material. In such a low γ-ray background environment, the signature of isomer depletion is not observed, and an upper limit of 2×10^{-5} is estimated for the excitation probability. This is consistent with the theoretical expectation. Our findings shed doubt on the previously reported NEEC phenomenon and highlight the necessity and feasibility of further experimental investigations for reexamining the isomer depletion under low γ-ray background.

In this paper, the electromagnetic deformation combined with heat treatment (ET) process was studied, which was meaningful for the forming of high performance Al-Li alloy sheet metal parts. In the ET process, the annealed sheet was firstly subjected to solution treatment, electromagnetic deformation. and artificial age until it reaches the peak aging state. Compared with the traditional T6 heat treatment, the time efficiency of the ET process is significantly improved, and the mechanical properties of the specimen are enhanced. The ET process only takes 6 hours to reach the peak aging, and the time efficiency of precipitate strengthening is reached up to 4 times compared with the T6 process. At the same time, the mechanical properties of the ET specimen are higher than the T6 one, an increase of 17.6% in Vickers hardness. Moreover, the mechanism of higher time efficiency and mechanical properties of the ET process is revealed. It is found that a high density of cellular dislocations and sub-grain were introduced during the electromagnetic deformation process, which is conducive to the nucleation and growth of the T1 precipitate during artificial aging. The T1 precipitates of the ET specimen are more dispersed and finer.

Epstein-Barr virus (EBV) infection is closely associated to liver injury with diverse clinical features in adolescents and adults. It is often manifested as infectious mononucleosis syndrome, sometimes causing self-limited acute hepatitis, with mild to moderate elevation of liver transaminases, and relative increase in age-related conditions. EBV infection can also cause cholestatic hepatitis, with elevated alkaline phosphatase and γ-glutamyltransferase as the main manifestations, accompanied by varying degrees of jaundice. A small number of patients with severe EBV infection may experience liver failure, and if left untreated in time, it may lead to high mortality. In addition, EBV infection is also associated with chronic hepatitis, liver cirrhosis, autoimmune liver disease, etc.EB病毒（EBV）感染与青少年和成人肝损伤密切相关，临床特征多样。常表现为传染性单核细胞增多症时的急性自限性肝炎，特点是以转氨酶轻、中度升高为主，随年龄增加病情相对加重。EBV感染还可致淤胆型肝炎，以碱性磷酸酶和γ-谷氨酰转移酶升高为主要表现，伴不同程度黄疸。少数EBV感染严重者可出现肝衰竭，如果不能及时治疗，病死率较高。此外，EBV感染与慢性肝炎、肝硬化、自身免疫性肝病等有一定关联。.