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1. Role of membrane mimetics on biophysical EPR studies of membrane proteins

   https://doi.org/10.1016/j.bbamem.2023.184138  

   Sahu, Indra D.; Lorigan, Gary A. (February 2023, Biochimica et Biophysica Acta (BBA) - Biomembranes)
2. Effect of Membrane Properties on the Carbonation of Anion Exchange Membrane Fuel Cells

   https://doi.org/10.3390/membranes11020102  

   Zheng, Yiwei; Irizarry Colón, Lyzmarie Nicole; Ul Hassan, Noor; Williams, Eric R.; Stefik, Morgan; LaManna, Jacob M.; Hussey, Daniel S.; Mustain, William E. (February 2021, Membranes)

   null (Ed.)

   Anion exchange membrane fuel cells (AEMFC) are potentially very low-cost replacements for proton exchange membrane fuel cells. However, AEMFCs suffer from one very serious drawback: significant performance loss when CO2 is present in the reacting oxidant gas (e.g., air) due to carbonation. Although the chemical mechanisms for how carbonation leads to voltage loss in operating AEMFCs are known, the way those mechanisms are affected by the properties of the anion exchange membrane (AEM) has not been elucidated. Therefore, this work studies AEMFC carbonation using numerous high-functioning AEMs from the literature and it was found that the ionic conductivity of the AEM plays the most critical role in the CO2-related voltage loss from carbonation, with the degree of AEM crystallinity playing a minor role. In short, higher conductivity—resulting either from a reduction in the membrane thickness or a change in the polymer chemistry—results in faster CO2 migration and emission from the anode side. Although this does lead to a lower overall degree of carbonation in the polymer, it also increases CO2-related voltage loss. Additionally, an operando neutron imaging cell is used to show that as AEMFCs become increasingly carbonated their water content is reduced, which further drives down cell performance. 

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3. On the performance of multilayered membrane filters

   https://doi.org/10.1007/s10665-021-10118-2  

   Fong, D.; Cummings, L. J.; Chapman, S. J.; Sanaei, P. (April 2021, Journal of Engineering Mathematics)

   null (Ed.)
4. Local, transient tensile stress on the nuclear membrane causes membrane rupture

   https://doi.org/10.1091/mbc.E18-09-0604  

   Zhang, Qiao; Tamashunas, Andrew C.; Agrawal, Ashutosh; Torbati, Mehdi; Katiyar, Aditya; Dickinson, Richard B.; Lammerding, Jan; Lele, Tanmay P.; Weaver, Valerie Marie (March 2019, Molecular Biology of the Cell)

   Cancer cell migration through narrow constrictions generates compressive stresses on the nucleus that deform it and cause rupture of nuclear membranes. Nuclear membrane rupture allows uncontrolled exchange between nuclear and cytoplasmic contents. Local tensile stresses can also cause nuclear deformations, but whether such deformations are accompanied by nuclear membrane rupture is unknown. Here we used a direct force probe to locally deform the nucleus by applying a transient tensile stress to the nuclear membrane. We found that a transient (∼0.2 s) deformation (∼1% projected area strain) in normal mammary epithelial cells (MCF-10A cells) was sufficient to cause rupture of the nuclear membrane. Nuclear membrane rupture scaled with the magnitude of nuclear deformation and the magnitude of applied tensile stress. Comparison of diffusive fluxes of nuclear probes between wild-type and lamin-depleted MCF-10A cells revealed that lamin A/C, but not lamin B2, protects the nuclear membranes against rupture from tensile stress. Our results suggest that transient nuclear deformations typically caused by local tensile stresses are sufficient to cause nuclear membrane rupture. 

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5. On the influence of pore connectivity on performance of membrane filters

   https://doi.org/10.1017/jfm.2020.520  

   Gu, B.; Renaud, D. L.; Sanaei, P.; Kondic, L.; Cummings, L. J. (November 2020, Journal of Fluid Mechanics)

   null (Ed.)

   We study the influence of a membrane filter's internal pore structure on its flow and adsorptive fouling behaviour. Membrane performance is measured via (1) comparison between volumetric flow rate and throughput during filtration and (2) control of concentration of foulants at membrane pore outlets. Taking both measures into account, we address the merits and drawbacks of selected membrane pore structures. We first model layered planar membrane structures with intra-layer pore connections, and present comparisons between non-connected and connected structures. Our model predicts that membrane filters with connected pore structures lead to higher total volumetric throughput than those with non-connected structures, over the filter lifetime. We also provide a sufficient criterion for the concentration of particles escaping the filter to achieve a maximum in time (indicative of a membrane filter whose particle retention capability can deteriorate). Additionally, we find that the influence of intra-layer heterogeneity in pore-size distribution on filter performance depends on the connectivity properties of the pores. 

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