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Understanding the mechanisms of the cellular aging processes is crucial for attempting to extend organismal lifespan and for studying age-related degenerative diseases. Yeast cells divide through budding, providing a classical biological model for studying cellular aging. With their powerful genetics, relatively short cell cycle, and well-established signaling pathways also found in animals, yeast cells offer valuable insights into the aging process. Recent experiments suggested the existence of two aging modes in yeast characterized by nucleolar and mitochondrial declines, respectively. By analyzing experimental data, this study shows that cells evolving into those two aging modes behave differently when they are young. While buds grow linearly in both modes, cells that consistently generate spherical buds throughout their lifespan demonstrate greater efficacy in controlling bud size and growth rate at young ages. A three-dimensional multiscale chemical-mechanical model was developed and used to suggest and test hypothesized impacts of aging on bud morphogenesis. Experimentally calibrated model simulations showed that during the early stage of budding, tubular bud shape in one aging mode could be generated by locally inserting new materials at the bud tip, a process guided by the polarized Cdc42 signal. Furthermore, the aspect ratio of the tubular bud could be stabilized during the late stage as observed in experiments in this work. The model simulation results suggest that the localization of new cell surface material insertion, regulated by chemical signal polarization, could be weakened due to cellular aging in yeast and other cell types, leading to the change and stabilization of the bud aspect ratio.

Over the past decades, the Hippo has been established as a crucial pathway involved in organ size control and cancer suppression. Dysregulation of Hippo signaling and hyperactivation of its downstream effector YAP are frequently associated with various human cancers. However, the underlying significance of such YAP activation in cancer development and therapy has not been fully characterized. In this study, we reported that the Hippo signaling deficiency can lead to a YAP-dependent oncogene addiction for cancer cells. Through a clinical compound library screen, we identified histone deacetylase (HDAC) inhibitors as putative inhibitors to suppress YAP expression. Importantly, HDAC inhibitors specifically targeted the viability and xenograft tumor growth for the cancer cells in which YAP is constitutively active. Taken together, our results not only establish an active YAP-induced oncogene addiction in cancer cells, but also lay the foundation to develop targeted therapies for the cancers with Hippo dysfunction and YAP activation.

BiFeO3@GO nanocomposite fibers were successfully synthesized by the electrospinning and simple ultrasound method. The structure, morphology, optical, composition and magnetic properties of BiFeO3@GO samples were characterized by XRD, FT-IR, SEM, TEM, UV–Vis and XPS analyses. The results showed that the removal of organic dye pollutants was enhanced by novel BiFeO3@GO fibers through the adsorption–photocatalytic synergy. The removal rates of methylene blue (MB), Congo red (CR), Rhodamine B (RHB) and norfloxacin (NOR) dyes were increased by 64.5%, 33.6%, 43% and 61.1%, respectively. Then it was a benefit to remove MB when the pH is between 6.0 and 10.0, while it was favorable for adsorption in a neutral environment and photocatalysis in an acidic or alkaline environment. The adsorption process of MB dyes was more in line with the pseudo-second-order kinetic model for BiFeO3@GO nanocomposite sample with 3 mg graphene oxide weight (GO3). The adsorption data were well fitted by Langmuir adsorption isotherm, which indicated that the adsorption process was a monolayer adsorption. The adsorption of MB dyes on GO3 nanocomposite fibers appeared to be a favorable process (0 < RL < 1). Moreover, the trapping experiments showed that ·OH was the main active substance during photocatalysis, and the FT-IR tests indicated that nanocomposite fibers can degrade MB into CO2 and H2O under the synergistic effect of adsorption and catalysis. [ABSTRACT FROM AUTHOR]

According to Moore's Law's development law, traditional floating gate memory is constrained by charge tunneling, and its size is approaching the physical limit, which is insufficient to meet the requirements of large data storage. The introduction of new information storage devices may be the key to overcoming the bottleneck. Resistive random access memory (RRAM) has garnered interest due to its fast switching speed, low power consumption, and high integration density. The resistive switching (RS) behaviors can be demonstrated in many materials, including transition metal oxides, perovskite oxides and organic matter, etc. Among these materials, graphene oxide (GO) with its unique physical, chemical properties and excellent mechanical properties is attracting significant attention for use in RRAM owing to its RS operation and potential for integration with other graphene-based electronics. However, there is unacceptable variability in RS reliability, including retention and endurance, which is the key factor that affects the development of memristors. In addition, the RS mechanism of GO-based RRAM has not been systematically discussed. In this article, we discuss systematically several typical models of the switching mechanism of GO-based RRAM and a summary of methods for improving the device's RS performance. This article concludes by discussing the applications of GO-RRAM in artificial neural networks, flexible devices, and biological monitoring. [ABSTRACT FROM AUTHOR]

An experimental investigation was conducted on a flexible riser with and without various helical strake coverages, with the aim of further improving the understanding of the response performance of the vortex-induced vibration (VIV) of a riser with helical strakes. Two current profiles, including uniform and linearly sheared currents, were simulated. The VIV displacements, VIV strains and hydrodynamic forces were directly measured from the test. Based on the fatigue damage method, the fatigue damage was obtained from the measured strain. Strakes with different coverages were analysed, and response parameters such as the displacement response and fatigue damage were studied. The results of the straked model test indicate that the response characteristics of a bare riser model can be quite distinct from those of a riser with helical strakes, and the response performance closely depends on the coverage of the helical strakes. The results also show that the flexible riser with 75% and 50% strake coverages are the best configurations to suppress VIV fatigue damage in uniform and linearly sheared currents, respectively. [ABSTRACT FROM AUTHOR]