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1. Imaging in lossy media

   https://doi.org/10.1088/1361-6420/acc2b4  

   Kim, Arnold; Tsogka, Chrysoula (March 2023, Inverse Problems)

   Abstract We study the effects of absorption in the medium on synthetic aperture imaging. We model absorption using the loss tangent, which is the imaginary part of the relative dielectric permittivity, and study two cases: (i) the loss tangent is known and (ii) the loss tangent is unknown. When the loss tangent is known and used in Kirchhoff migration (KM), we find that images of targets are range-shifted by approximately a central wavelength so that their predicted locations are closer to the synthetic aperture than they actually are. In contrast, we find that when the medium is unknown, the KM image does not exhibit this range-shift. Hence, we determine that it is better to not make use of any knowledge of the absorption when imaging. Using a recently developed transformation of KM images, which we call reciprocal-KM (rKM), we achieve tunably high-resolution images of targets through adjusting the value of a user-defined parameterε. When rKM is applied to an imaging region containing two targets, we find that their predicted locations shift, especially in range, but within a fraction of central wavelength of their true locations. 

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2. Spent media analysis suggests cultivated meat media will require species and cell type optimization

   https://doi.org/10.1038/s41538-022-00157-z  

   O’Neill, Edward N.; Ansel, Joshua C.; Kwong, Grace A.; Plastino, Michael E.; Nelson, Jenny; Baar, Keith; Block, David E. (September 2022, npj Science of Food)

   Abstract Cell culture media design is perhaps the most significant hurdle currently facing the commercialization of cultivated meat as an alternative source of dietary protein. Since media optimization for a specific culture system requires a significant amount of effort and investment, a major question remaining is whether media formulations can be easily shared across multiple production schemes for cells of different species and lineages. Here, we perform spent medium analysis to compare the specific nutrient utilization of primary embryonic chicken muscle precursor cells and fibroblasts to the murine C2C12 myoblast cell line. We demonstrate that these related cell types have significantly different nutrient utilization patterns collectively and on a per-cell basis, and that many components of conventional media do not appear to be depleted by the cells. Namely, glucose was not consumed as rapidly nor as completely by the chicken muscle precursors compared to other cells overall, and there were significant differences in specific consumption rates for several other key nutrients over the first day of culture. Ultimately, our results indicate that no one medium is likely ideal and cost effective to culture multiple cell types and that novel methods to streamline media optimization efforts will be important for the industry to develop. 

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3. Media use and vaccine resistance

   https://doi.org/10.1093/pnasnexus/pgad146  

   Green, Jon; Druckman, James N; Baum, Matthew A; Ognyanova, Katherine; Simonson, Matthew D; Perlis, Roy H; Lazer, David (May 2023, PNAS Nexus)

   Mutz, Diana (Ed.)

   Abstract Public health requires collective action—the public best addresses health crises when individuals engage in prosocial behaviors. Failure to do so can have dire societal and economic consequences. This was made clear by the disjointed, politicized response to COVID-19 in the United States. Perhaps no aspect of the pandemic exemplified this challenge more than the sizeable percentage of individuals who delayed or refused vaccination. While scholars, practitioners, and the government devised a range of communication strategies to persuade people to get vaccinated, much less attention has been paid to where the unvaccinated could be reached. We address this question using multiple waves of a large national survey as well as various secondary data sets. We find that the vaccine resistant seems to predictably obtain information from conservative media outlets (e.g. Fox News) while the vaccinated congregate around more liberal outlets (e.g. MSNBC). We also find consistent evidence that vaccine-resistant individuals often obtain COVID-19 information from various social media, most notably Facebook, rather than traditional media sources. Importantly, such individuals tend to exhibit low institutional trust. While our results do not suggest a failure of sites such as Facebook's institutional COVID-19 efforts, as the counterfactual of no efforts is unknown, they do highlight an opportunity to reach those who are less likely to take vital actions in the service of public health. 

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4. On electroconvection in porous media

   https://doi.org/10.1512/iumj.2023.72.9572  

   Abdo, Elie; Ignatova, Mihaela (January 2023, Indiana University Mathematics Journal)
5. Elastoviscoplastic flows in porous media

   https://doi.org/10.1016/j.jnnfm.2018.04.006  

   De Vita, F.; Rosti, M.E.; Izbassarov, D.; Duffo, L.; Tammisola, O.; Hormozi, S.; Brandt, L. (August 2018, Journal of Non-Newtonian Fluid Mechanics)