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The role of interfacial coatings in gas transport dynamics in foam coarsening is often difficult to quantify. The complexity of foam coarsening measurements or gas transport measurements between bubbles requires assumptions about the liquid thin film thickness profile in order to explore the effects of interfacial coatings on gas transport. It should be possible to independently quantify the effects from changes in film thickness and interfacial permeability by using both atomic force microscopy and optical microscopy to obtain time snapshots of this dynamic process. Further, it is expected that the surfactant and polymer interfacial coatings will affect the mass transfer differently. We measure the mass transfer between the same nitrogen microbubbles pairs in an aqueous solution using two methods simultaneously. First, we quantify the bubble volume changes with time via microscopy and second, we use Atomic Force Microscopy to measure the film thickness and mass transfer resistances using a model for the gas transport. Modelling of the interface deformation, surface forces and mass transfer across the thin film agrees with independent measurements of changes in bubble size. We demonstrate that an anionic surfactant does not provide a barrier to mass transfer, but does enhance mass transfer above the critical micelle concentration. In contrast, a polymer monolayer at the interface does restrict mass transfer. [ABSTRACT FROM AUTHOR]

[Display omitted] Due to the high incidence of kidney disease, there is an urgent need to develop wearable artificial kidneys. This need is further exacerbated by the coronavirus disease 2019 pandemic. However, the dialysate regeneration system of the wearable artificial kidney has a low adsorption capacity for urea, which severely limits its application. Therefore, nanomaterials that can effectively remove uremic toxins, especially urea, to regenerate dialysate are required and should be further investigated and developed. Herein, flower-like molybdenum disulphide (MoS 2) nanosheets decorated with highly dispersed cerium oxide (CeO 2) were prepared (MoS 2 /CeO 2), and their adsorption performances for urea, creatinine, and uric acid were studied in detail. Due to the open interlayer structures and the combination of MoS 2 and CeO 2 , which can provide abundant adsorption active sites, the MoS 2 /CeO 2 nanomaterials present excellent uremic toxin adsorption activities. Further, uremic toxin adsorption capacities were also assessed using a self-made fixed bed device under dynamic conditions, with the aim of developing MoS 2 /CeO 2 for the practical adsorption of uremic toxins. In addition, the biocompatibility of MoS 2 /CeO 2 was systematically analyzed using hemocompatibility and cytotoxicity assays. Our data suggest that MoS 2 /CeO 2 can be safely used for applications requiring close contact with blood. Our findings confirm that novel 2-dimensional nanomaterial adsorbents have significant potential for dialysis fluid regeneration. [ABSTRACT FROM AUTHOR]

Melanoma, arising from the malignant transformation of melanocytes, stands as the most lethal type of skin cancer. While significant strides have been made in targeted therapy and immunotherapy, substantially enhancing therapeutic efficacy, the prognosis for melanoma patients remains unoptimistic. SIRT7, a nuclear-localized deacetylase, plays a pivotal role in maintaining cellular homeostasis and adapting to external stressors in melanoma, with its activity closely tied to intracellular nicotinamide adenine dinucleotide (NAD+). However, its involvement in adaptive resistance to targeted therapy remains unclear. Herein, we unveil that up-regulated SIRT7 promotes mitochondrial biogenesis to render the adaptive resistance to MAPK inhibition in melanoma. Initially, we observed a significant increase of SIRT7 expression in publicly available datasets following targeted therapy within a short duration. In consistent, we found elevated SIRT7 expression in melanoma cells subjected to BRAF or MEK inhibitors in vitro. The up-regulation of SIRT7 expression was also confirmed in xenograft tumors in mice after targeted therapy in vivo. Furthermore, we proved that SIRT7 deficiency led to decreased cell viability upon prolonged exposure to BRAF or MEK inhibitors, accompanied by an increase in cell apoptosis. Mechanistically, SIRT7 deficiency restrained the upregulation of genes associated with mitochondrial biogenesis and intracellular ATP levels in response to targeted therapy treatment in melanoma cells. Ultimately, we proved that SIRT7 deficieny could sensitize BRAF -mutant melanoma cells to MAPK inhibition targeted therapy in vivo. In conclusion, our findings underscore the role of SIRT7 in fostering adaptive resistance to targeted therapy through the facilitation of mitochondrial biogenesis. Targeting SIRT7 emerges as a promising strategy to overcome MAPK inhibitor adaptive resistance in melanoma. • SIRT7 expression is prominently up-regulated in BRAF -mutant melanoma cells upon the treatment with MAPK pathway inhibitor. • SIRT7 is pivotal in promoting adaptive resistance to targeted therapy by facilitating mitochondrial biogenesis. • Targeting SIRT7 emerges as a promising strategy to counter adaptive resistance to MAPK inhibitors in melanoma. [ABSTRACT FROM AUTHOR]

Cancer is a disease that evolves continuously with unpredictable outcomes. Although conventional chemotherapy can display significant antitumor effects, the lack of specificity and poor bioavailability remain major concerns in cancer therapy. Moreover, with the advent of novel anti-cancer gene therapies, there is an urgent need for drug delivery vectors capable of bypassing cellular barriers and efficiently transferring therapeutic cargo to recipient cells. A number of drug delivery systems have been proposed to overcome these limitations, but their successful clinical translation has been hampered by the onset of unexpected side effects and associated toxicities. The application of extracellular vesicles (EVs), a class of naturally released, cell-derived particles, as drug delivery vectors presents a breakthrough in nanomedicine, taking into account their biocompatibility and natural role in intercellular communication. Combining the advantageous intrinsic properties of EVs with surface functionalization and the encapsulation of drugs allows for a new class of engineered EVs that serve as effective therapeutic carriers. Here, we describe the various successful approaches involving the application of engineered EVs as bio-derived drug delivery vectors in cancer therapy. The latest and most effective strategies of engineering EVs to improve drug loading, stealth properties and tumour targeting capabilities of EVs are debated. Finally, current obstacles and future perspectives of smart engineered EVs are discussed. [ABSTRACT FROM AUTHOR]

Taxis are an important component of urban passenger transport. Research on the daily dispatching of taxis and the utility of governmental management is important for the improvement of passenger travel, taxi driver income and environmental impacts. However, urban taxi management is a complex and dynamic system that is affected by many factors, and positive/negative feedback relationships and nonlinear interactions exist between each subsystem and variable. Therefore, conventional research methods can hardly depict its characteristics comprehensively. To bridge this gap, this paper develops a system dynamics model of urban taxi management, in which the empty-loaded rate and total demand are selected as key factors affecting taxi dispatching, and the impacts of taxi fares on driver income and travel demand are taken into account. After the validation of the model, taxi operations data derived from a prior analysis of origin–destination data of Beijing taxis are used as input for the model to simulate the taxi market in Beijing. Finally, economic and environmental implications are provided for the government to optimise policies on taxi management. [ABSTRACT FROM AUTHOR]