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Modern life requires many different metal ions, which enable diverse biochemical functions. It is commonly assumed that metal ions' environmental availabilities controlled the evolution of early life. We argue that evolution can only explore the chemistry that life encounters, and fortuitous chemical interactions between metal ions and biological compounds can only be selected for if they first occur sufficiently frequently. We calculated maximal transition metal ion concentrations in the ancient ocean, determining that the amounts of biologically important transition metal ions were orders of magnitude lower than ferrous iron. Under such conditions, primitive bioligands would predominantly interact with Fe(II). While interactions with other metals in certain environments may have provided evolutionary opportunities, the biochemical capacities of Fe(II), Fe-S clusters, or the plentiful magnesium and calcium could have satisfied all functions needed by early life. Primitive organisms could have used Fe(II) exclusively for their transition metal ion requirements. [ABSTRACT FROM AUTHOR]

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The current study attempted to introduce nano-aluminium oxide (Al2O3) particles into ZE41 alloy via friction stir processing (FSP). The effect of these nano-Al2O3 particles on the mechanical and tribological characteristics of ZE41 alloy is investigated. The results of microstructural studies revealed the uniform distribution of Al2O3 particles and substantial grain refinement in the stir zone by FSP. Enhanced microhardness was observed in the processed region due to the grain refinement and the occurrence of regularly distributed Al2O3 particles. The wear resistance was also seen increased with the incorporation of the Al2O3 particles. Moreover, the effect of FSP parameters on the successful incorporation of nano-Al2O3 particles in ZE41 alloy without any defect is also realised. [ABSTRACT FROM AUTHOR]

This work focused on improving the weld quality and productivity of dissimilar friction stir welding of AA 7075-T6 and AA 2024-T3 aluminium alloys by controlling the process parameters of tool axial force, welding speed, tool offset, and rotational speed. A newly developed hybrid pentagonal tool is used for the fabrication of welds to enhance productivity. In this study, an RSM based on a central composite method is used for the design of experiments, optimisation, and data analysis. The result found that the ideal range of welding process parameters for 6-mm-thick AA7075-T6 and AA2024-T3 aluminium alloys by friction stir welding is to use a tool spindle rotational speed of 1178.51 rpm, an axial load of 7.78 KN, a traverse speed of 132.74 mm/min, and 0.958 mm tool offset towards the AA2024-T3 material side. Based on the UTS, a joint efficiency of 67.19% is achieved. It is observed that while increasing the value of FSW parameters like tool spindle rotational speed and traverse speed, the tensile strength and elongation values tend to increase drastically after further increasing those parameters, UTS and TE seem to decrease. [ABSTRACT FROM AUTHOR]

The last two decades have witnessed a major revolution in the field of tumor immunology including clinical progress using various immunotherapy strategies. These advances have highlighted the potential for approaches that harness the power of the immune system to fight against cancer. While cancer immunotherapies have shown significant clinical successes, patient responses vary widely due to the complex and heterogeneous nature of tumors and immune responses, calling for reliable biomarkers and therapeutic strategies to maximize the benefits of immunotherapy. Especially, stratifying responding individuals from non-responders during the early stages of treatment could help avoid long-term damage and tailor personalized treatments. In efforts to develop non-invasive means for accurately evaluating and predicting tumor response to immunotherapy, multiple affinity-based agents targeting immune cell markers and checkpoint molecules have been developed and advanced to clinical trials. In addition, researchers have recently turned their attention to substrate and activity-based imaging probes that can provide real-time, functional assessment of immune response to treatment. Here, we highlight some of those recently designed probes that image functional proteases as biomarkers of cancer immunotherapy with a focus on their chemical design and detection modalities and discuss challenges and opportunities for the development of imaging tools utilized in cancer immunotherapy., (© 2023 Wiley-VCH GmbH.)