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In-situ electron irradiation and aging are applied to introduce high-density precipitates in an Mg-10Gd-3Y-1Zn-0.5Zr (GWZ1031K, wt.%) alloy to improve the hardness. The results show that the hardness of the Mg alloy after irradiation for 10 h and aging for 9 h at 250 °C is 1.64 GPa, which is approximately 64% higher than that of the samples before being treated. It is mainly attributed to γ′ precipitates on the basal plane after irradiation and the high-density nanoscale β′ precipitates on the prismatic plane after aging, which should be closely related to the irradiation-induced homogenous clusters. The latter plays a key role in precipitation hardening. This result paves a way to improve the mechanical properties of metallic materials by tailoring the precipitation through irradiation and aging.

Nucleoside triphosphate pyrophosphohydrolase (NTP-PPase) functions as one of the mechanisms to guarantee the fidelity of DNA replication through the cleavage of non-canonical nucleotides into di- or monophosphates. Human NTP-PPase is poorly understood and investigated. In the present study, by using tissue microassays with the paired cancer and adjacent regions, we found that with the prevalent expression of dCTP pyrophosphohydrase (DCTPP1) in the cytosol and nucleus in tumors investigated, DCTPP1 was inclined to accumulate in the nucleus of cancer cells compared to the paired adjacent tissue cells in multiple carcinoma including lung, breast, liver, cervical, gastric and esophagus cancer. More significantly, the higher DCTPP1 expression in the nucleus of lung, gastric and esophagus cancer cells was associated with histological subtypes. The nucleic accumulation of DCTPP1 was apparently observed as well when cancer cell line MCF-7 was treated with H2O2 in vitro. Considering the roles of DCTPP1 on restricting the concentration of non-canonical nucleotides in the nucleotide pool, accumulation of DCTPP1 in the nucleus of cancer cells might suffice for maintaining the proper DNA replication in order to fulfill the requirement for the survival and proliferation of tumor cells.