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Superoxide dismutase (SOD) is one of the major antioxidants in vivo and is expected to play critical roles on the defense against reactive oxygen species (ROS)-mediated damages, such as ionizing radiation damages. Herein, inspired by the function and structure of natural SODs and cerium oxide nanozymes, two monovalent cerium-based metal organic frameworks (Ce-MOFs), CeIIIBTC and CeIVBTC, were designed for superoxide radical (O2 •–) elimination and ionizing radiation protection. These two Ce-MOFs selectively scavenge O2 •– and are excellent SOD mimics. Like natural SODs and cerium oxide nanozymes, the SOD-like catalytic mechanism of Ce-MOFs involves a cycle between Ce(IV) and Ce(III). Furthermore, by constructing monovalent Ce-MOFs, we found that high-valent CeIVBTC are more effective SOD-like nanozymes compared to CeIIIBTC. With smaller size, better monodispersity, and more effective SOD-like activity, CeIVBTC nanozymes were further applied for ionizing radiation protection. Both in vitro and in vivo results demonstrated that CeIVBTC nanozymes could efficiently scavenge ROS, prevent cells from γ-ray radiation-induced cell viability decrease and DNA damages, and improve the survival rate of irradiated mice by recovering the bone marrow DNA damage and alleviating oxidative stress of tissues. The protective effect and good biocompatibility of CeIVBTC nanozymes will enable the development of Ce-MOFs-based radioprotectants and facilitate treatment of other ROS-related diseases.

2) have been synthesized under hydrothermal conditions. In compound 1, 2D {[Gd 2 (CO 3 ) 2 ] 2+ } n sheets are connected by [Cu(pydc) 2 ] 2bridges, which give rise to the formation of a sandwichlike framework. Compound 2 exhibits a 3D framework constructed by Gd 4 clusters, Co 2 subunits, and pydc spacers. The solid-state dc magnetic measurements reveal antiferromagnetic behaviors of 1 and 2 in both compounds.

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Memory forensic tools provide a thorough way to detect malware and investigate cyber crimes. However, existing memory forensic tools must be compiled against the exact version of the kernel source code and the exact kernel configuration. This poses a problem for Android devices because there are more than 1,000 manufacturers and each manufacturer maintains its own kernel. Moreover, new security enhancements introduced in Android Lollipop prevent most memory acquisition tools from executing. This chapter describes AMExtractor, a tool for acquiring volatile physical memory from a wide range of Android devices with high integrity. AMExtractor uses /dev/kmem to execute code in kernel mode, which is supported by most Android devices. Device-specific information is extracted at runtime without any assumptions about the target kernel source code and configuration. AMExtractor has been successfully tested on several devices shipped with different versions of the Android operating system, including the latest Android Lollipop. Memory images dumped by AMExtractor can be exported to other forensic frameworks for deep analysis. A rootkit was successfully detected using the Volatility Framework on memory images retrieved by AMExtractor.

Background As we know, radiotherapy plays an irreplaceable role in the clinical management on solid tumors. However, due to the non-specific killing effects of ionizing radiation, normal tissues damages would be almost simultaneous inevitably. Therefore, ideal radioprotective agents with high efficiency and low toxicity are always desirable. In this work, atomically precise Ag14 clusterzymes were developed, and their applications in radioprotection were studied in vitro and in vivo for the first time. Methods The ultra-small glutathione supported Ag14 clusterzymes were synthesized by convenient sodium borohydride (NaBH4) reduction of thiolate-Ag (I) complexes and then they were purified by desalting columns. The enzyme-like activity and antioxidant capacity of Ag14 clusterzymes have been tested by various commercial kits, salicylic acid method and electron spin resonance (ESR). Next, they were incubated with L929 cells to evaluate whether they could increase cell viability after γ-ray irradiation. And then Ag14 clusterzymes were intravenously injected into C57 mice before 7 Gy whole-body γ-ray irradiation to evaluate the radioprotection effects in vivo. At last, the in vivo toxicities of Ag14 clusterzymes were evaluated through biodistribution test, hematological details, serum biochemical indexes and histological test in female Balb/c mice with intravenous injection of Ag14 clusterzymes. Results Our studies suggested atomically precise Ag14 clusterzymes were potential radioprotectants. Ag14 clusterzymes exhibited unique superoxide dismutase (SOD)-like activity, strong anti-oxidative abilities, especially on •OH scavenging. The Ag14 clusterzymes could effectively improve cell viability through eliminating ROS and prevent DNA damages in cells dealt with γ-ray irradiation. In vivo experiments showed that Ag14 clusterzymes could improve the irradiated mice survival rate by protecting hematological systems and repairing tissue oxidative stress damage generated by γ-ray irradiation. In addition, bio-distribution and toxicological experiments demonstrated that the ultrasmall Ag14 clusterzymes could be excreted quickly from the body by renal clearance and negligible toxicological responses were observed in mice up to 30 days. Conclusion In summary, atomically precise, ultrasmall and water soluble Ag14 clusterzymes with SOD-like activity were successfully developed and proved to be effective both in vitro and in vivo for radioprotection. Furthermore, with atomically precise molecular structure, Ag14 clusterzymes, on aspect of the catalytic and optical properties, may be improved by structure optimization on atom-scale level for other applications in disease diagnosis and treatment. Graphical Abstract

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