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Air pockets can become trapped at high points in pipelines with irregular profiles, particularly during service interruptions. The resulting issues, primarily caused by peak pressures generated during pipeline filling, are a well-documented topic in the literature. However, it is surprising that this subject has not received comprehensive attention. Using a model developed by the authors, this paper identifies the key parameters that define the phenomenon, presenting equations in a dimensionless format. The main advantage of this study lies in the ability to easily compute pressure surges without the need to solve a complex system of differential and algebraic equations. Numerous cases of filling operations were analysed to obtain dimensionless charts that can be used by water utilities to compute pressure surges during filling operations. Additionally, it provides charts that facilitate the rapid and reasonably accurate estimation of peak pressures. Depending on their transient characteristics, pressure peaks are either slow or fast, with separate charts provided for each type. A practical application involving a water pipeline with an irregular profile demonstrates the model's effectiveness, showing strong agreement between calculated and chart-predicted (proposed methodology) values. This research provides water utilities with the ability to select the appropriate pipe's resistance class required for water distribution systems by calculating the pressure peak value that may occur during filling procedures. [ABSTRACT FROM AUTHOR]

Flexible thin-film electronics based on functionalized laser-induced graphene (LIG) hold great promise for a diverse range of applications, including biosensors and energy storage devices. In this study, we present a simple and direct method for synthesizing LIG functionalized with a copper-based metal-organic framework (MOF). The proposed synthesis procedure involves a one-step laser photothermal process on the surface of a carbon-rich polyimide to obtain LIG, followed by a simple layer-by-layer technique for growing Cu-BTC crystals within the porous structure of LIG. Structural characterization through various techniques confirms the successful deposition of crystalline Cu-BTC within the electrically conductive LIG surface. Cu-BTC@LIG composites are highly valuable candidate materials for multiple applications. In particular, we demonstrate the use of Cu-BTC@LIG as an electrode for electrochemical supercapacitors, increasing the specific capacitance by up to six times compared to LIG-only electrodes (reaching values of 2.8 mF cm-2 at 54.3 μA cm-2 or 2.1 mF cm-2 at 10 mV s-1) due to the double layer capacitance and pseudocapacitance contribution of Cu-BTC. The Cu-BTC@LIG electrodes also exhibit superior energy density (7.4 times higher at a power density of 21.26 μW cm-2) and stability over multiple charge-discharge cycles (45000), making it a promising material not only for energy-storage devices but also for numerous applications in flexible electronics. [ABSTRACT FROM AUTHOR]

This review focuses on the role of small extracellular vesicles in the pathophysiological mechanisms of retinal degenerative diseases. Many of these mechanisms are related to or modulated by the oxidative burden of retinal cells. It has been recently demonstrated that cellular communication in the retina involves extracellular vesicles and that their rate of release and cargo features might be affected by the cellular environment, and in some instances, they might also be mediated by autophagy. The fate of these vesicles is diverse: they could end up in circulation being used as markers, or target neighbor cells modulating gene and protein expression, or eventually, in angiogenesis. Neovascularization in the retina promotes vision loss in diseases such as diabetic retinopathy and age-related macular degeneration. The importance of micro RNAs, either as small extracellular vesicles' cargo or free circulating, in the regulation of retinal angiogenesis is also discussed. [ABSTRACT FROM AUTHOR]

Exosomes or small extracellular vesicles (sEVs) represent a pivotal component in intercellular communication, carrying a diverse array of biomolecules. Several factors can affect sEVs release dynamics, as occurs in hyperglycemia or inflammation. In fact, sEVs release has been associated with the promotion of physio-pathological processes. Among the sEVs cargo, microRNAs play an essential role in cell-to-cell regulation. More concretely, miR-205-5p is related to angiogenesis and cell proliferation. The aim of this study is to understand the specific role of sEVs containing miR-205-5p under high glucose conditions. ARPE-19 cells were cultured with high glucose (HG) for 5 days. sEVs were isolated and characterized. sEVs from ARPE-19 were used for angiogenesis and cell proliferation. HG increased sEVs release but downregulated miR-205-5p cargo expression compared to the control. sEVs from HG-treated ARPE-19 cells promoted tube formation and migration processes. In contrast, miR-205-5p overexpression (by mimic transfection) decreased angiogenesis and cell migration. Our results demonstrate how ARPE-19 cells respond to HG challenge by increasing sEVs with weak miR-205-5p cargo. The absence of this miRNA in sEVs is enough to promote angiogenesis. In contrast, restoring sEVs-miR-205-5p levels decreased it. These findings open new possibilities in sEVs-based therapies containing miR-205-5p against angiogenesis. [ABSTRACT FROM AUTHOR]