Detachment of Liquid-Water Droplets from Gas-Diffusion Layers

A critical issue for optimal water management in proton-exchange-membrane fuel cells at lower temperatures is the removal of liquid water from the cell. This pathway is intimately linked with the phenomena of liquid-water droplet removal from surface of the gas-diffusion layer and into the flow channel. Thus, a good understanding of liquid-water transport and droplet growth and detachment from the gas-diffusion layer is critical. In this study, liquid-water droplet growth and detachment on the gas-diffusion layer surfaces are investigated experimentally to improve the understating of water transport through and removal from gas-diffusion layers. An experiment using a sliding-angle measurement is designed and used to quantify and directly measure the adhesion force for liquid-water droplets, and to understand the droplets? growth and detachment from the gas-diffusion layers

Detachment of Liquid-Water Droplets from Gas-Diffusion Layers

A critical issue for optimal water management in proton-exchange-membrane fuel cells at lower temperatures is the removal of liquid water from the cell. This pathway is intimately linked with the phenomena of liquid-water droplet removal from surface of the gas-diffusion layer and into the flow channel. Thus, a good understanding of liquid-water transport and droplet growth and detachment from the gas-diffusion layer is critical. In this study, liquid-water droplet growth and detachment on the gas-diffusion layer surfaces are investigated experimentally to improve the understating of water transport through and removal from gas-diffusion layers. An experiment using a sliding-angle measurement is designed and used to quantify and directly measure the adhesion force for liquid-water droplets, and to understand the droplets? growth and detachment from the gas-diffusion layers

Regulation of cerebral blood flow boosts precise brain targeting of vinpocetine-derived ionizable-lipidoid nanoparticles

Abstract Despite advances in active drug targeting for blood-brain barrier penetration, two key challenges persist: first, attachment of a targeting ligand to the drug or drug carrier does not enhance its brain biodistribution; and second, many brain diseases are intricately linked to microcirculation disorders that significantly impede drug accumulation within brain lesions even after they cross the barrier. Inspired by the neuroprotective properties of vinpocetine, which regulates cerebral blood flow, we propose a molecular library design centered on this class of cyclic tertiary amine compounds and develop a self-enhanced brain-targeted nucleic acid delivery system. Our findings reveal that: (i) vinpocetine-derived ionizable-lipidoid nanoparticles efficiently breach the blood-brain barrier; (ii) they have high gene-loading capacity, facilitating endosomal escape and intracellular transport; (iii) their administration is safe with minimal immunogenicity even with prolonged use; and (iv) they have potent pharmacologic brain-protective activity and may synergize with treatments for brain disorders as demonstrated in male APP/PS1 mice

Circulating neutrophils and tumor-associated myeloid cells function as a powerful biomarker for response to chemoradiation in locally advanced cervical cancer

Purpose: The immune system’s role in mediating the cytotoxic effects of chemoradiotherapy remains not completely understood. The integration of immunotherapies into treatment will require insight into features and timing of the immune microenvironment associated with treatment response. Here, we investigated the role of circulating neutrophils and tumor-associated myeloid cells (TSAMs) as potential agents and biomarkers for disease-related outcomes in locally advanced cervical cancer (LACC). Material and Methods: Hematologic parameters for two LACC patient cohorts, a retrospective clinical and a prospective translational cohort, were obtained at baseline, weekly during chemoradiotherapy for the retrospective cohort, biweekly during chemoradiotherapy for the prospective cohort, and at the first follow-up visit for both cohorts (mean 14.7 weeks, range 8.1–25.1 weeks for the prospective cohort and 5.3 weeks with a range of 2.7–9.0 weeks for the retrospective cohort). In both cohorts, baseline as well as mean and lowest on-treatment values for platelets, hemoglobin, absolute neutrophil count (ANC), and absolute lymphocyte count (ALC) were analyzed for correlations with disease-related outcomes. In the prospective cohort, circulating myeloid cells were isolated from peripheral blood mononuclear cells (PBMCs), and TSAMs were isolated from tumor tissue via a novel serial cytobrush sampling assay. The samples were analyzed by flow cytometry. Results: In both cohorts, the only hematologic parameter significantly associated with survival was elevated on-treatment mean ANC (mANC), which was associated with lower local failure-free and overall survival rates in the retrospective and prospective cohorts, respectively. mANC was not associated with a difference in distant metastases. CD11b+CD11c- TSAMs, which act as a surrogate marker for intratumoral neutrophils, steadily decreased during the course of chemoRT and nadier’d at week 5 of treatment. Conversely, circulating myeloid cells identified from PBMCs steadily increased through week 5 of treatment. Regression analysis confirmed an inverse relationship between circulating myeloid cells and TSAMs at this time point. Conclusions: These findings identify on-treatment mean neutrophil count as a predictor of disease-related outcomes, suggest that neutrophils contribute to chemoradiation treatment resistance, and demonstrate the importance of techniques to measure intratumoral immune activity

Effects of Relative Humidity and Spraying Medium on UV Decontamination of Filters Loaded with Viral Aerosols

Although respirators and filters are designed to prevent the spread of pathogenic aerosols, a stockpile shortage is anticipated during the next flu pandemic. Contact transfer and reaerosolization of collected microbes from used respirators are also a concern. An option to address these potential problems is UV irradiation, which inactivates microbes by dimerizing thymine/uracil in nucleic acids. The objective of this study was to determine the effects of transmission mode and environmental conditions on decontamination efficiency by UV. In this study, filters were contaminated by different transmission pathways (droplet and aerosol) using three spraying media (deionized water [DI], beef extract [BE], and artificial saliva [AS]) under different humidity levels (30% [low relative humidity {LRH}], 60% [MRH], and 90% [HRH]). UV irradiation at constant intensity was applied for two time intervals at each relative humidity condition. The highest inactivation efficiency (IE), around 5.8 logs, was seen for DI aerosols containing MS2 on filters at LRH after applying a UV intensity of 1.0 mW/cm(2) for 30 min. The IE of droplets containing MS2 was lower than that of aerosols containing MS2. Absorption of UV by high water content and shielding of viruses near the center of the aggregate are considered responsible for this trend. Across the different media, IEs in AS and in BE were much lower than in DI for both aerosol and droplet transmission, indicating that solids present in AS and BE exhibited a protective effect. For particles sprayed in a protective medium, RH is not a significant parameter