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The intricate network of cell functions relies on gene expression programs, where the whole RNA life cycle from DNA to protein is subjected to extensive transcriptional and post‐transcriptional gene regulation events. Established bulk RNA sequencing methods provide an averaged, transcriptome‐wide quantification of the RNA life cycle, including transcription, processing, translation, transport, and degradation through RNA‐protein interactions. Furthermore, numerous studies using bulk epitranscriptomic profiling unveiled that dynamic RNA modifications (e. g., N6‐Methyladenosine), add another layer of gene regulations. However, many regulatory events are cell‐type specific, subcellularly localized, and subjected to cell‐cell communications within the native tissue environment. Thanks to the advances in single‐cell sequencing, spatial sequencing, and highly multiplexed imaging methods, we can routinely measure single‐cell and spatial transcriptomics. Yet more comprehensive methods to profile every step of the RNA life cycle with single‐cell and spatial information are still lacking. In this review, we will summarize and compare early explorations in developing state‐of‐the‐art methods for spatially and single‐cell resolved mapping of RNA kinetics, translation, RNA‐protein interactions, and epitranscriptomics. It is promising that these new techniques will greatly facilitate our understanding of the RNA‐centered regulation landscapes in different cell types and how the post‐transcriptional regulations are interconnected within cellular and tissue architecture. [ABSTRACT FROM AUTHOR]

Titanium alloy pressure spherical–cylindrical shells enable the effective utilization of the strength of spherical and cylindrical pressure-resistant shell components. In this study, a numerical simulation of the residual stress of a titanium alloy butt-welding plate was conducted by employing sequential coupling and a temperature heat source model. The results of welding residual stress analysis agreed well with the experimental results reported in the literature. Subsequently, the welding residual stress of a titanium alloy pressure spherical–cylindrical shell was calculated and analyzed using the same method. Finally, the influence of residual stress on the ultimate bearing capacity of the shell was assessed. On the inner surface of the shell, the horizontal welding residual tensile stress, perpendicular to the weld path, exhibited a bimodal distribution. The longitudinal welding residual tensile stresses were higher than the horizontal welding residual stress. Near the weld on the outer shell surface, higher longitudinal welding residual tensile stresses existed, whereas the horizontal welding residual stress was compressive. Both the inner and outer shell surfaces exhibited significant longitudinal residual tensile stresses along the weld path, though residual compressive stresses existed on both surfaces. The influence of welding residual stress on the ultimate load-bearing capacity of the shell was minimal. [ABSTRACT FROM AUTHOR]

In order to alleviate the problem that there is increasingly floating garbage pollution on the sea, this paper proposes a new design of floating garbage cleaning equipment. This equipment is a slender structure, and whether its structural strength can meet the design requirements requires special attention. In order to ensure the rationality and safety of the design, load calculation and strength analysis are carried out based on the design wave method. The calculation results show that the longitudinal torque load of this equipment is the largest, which is 2.5 times of the second largest vertical bending moment. At the same time, there are three large stress areas in the floating structure, which are the connection between the pontoon and the connecting buntons, the connecting buntons intersecting with the Y axis and the pontoons on both sides. For the abovementioned high-stress areas, a structural strengthening plan is proposed. After the improvement, the stress in the high-stress areas of the structure is significantly reduced, with a maximum reduction of 52%. The strength of the improved structure meets the design requirements. The research results of this paper can provide relevant references for the development of floating garbage cleaning equipment in the future.