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Epistasis - the interaction between alleles at different genetic loci - plays a fundamental role in biology. However, several recent approaches quantify epistasis using a chimeric formula that measures deviations from a multiplicative fitness model on an additive scale, thus mixing two scales. Here, we show that for pairwise interactions, the chimeric formula yields a different magnitude but the same sign of epistasis compared to the multiplicative formula that measures both fitness and deviations on a multiplicative scale. However, for higher-order interactions, we show that the chimeric formula can have both different magnitude and sign compared to the multiplicative formula. We resolve these inconsistencies by deriving mathematical relationships between the different epistasis formulae and different parametrizations of the multivariate Bernoulli distribution. We argue that the chimeric formula does not appropriately model interactions between the Bernoulli random variables. In simulations, we show that the chimeric formula is less accurate than the classical multiplicative/additive epistasis formulae and may falsely detect higher-order epistasis. Analyzing multi-gene knockouts in yeast, multi-way drug interactions in E. coli, and deep mutational scanning of several proteins, we find that approximately 10% to 60% of inferred higher-order interactions change sign using the multiplicative/additive formula compared to the chimeric formula. Epistasis can be quantified using the chimeric formula, which mixes additive and multiplicative scales. Here, the authors show that this formula does not appropriately quantify higher-order epistasis. [ABSTRACT FROM AUTHOR]

The article reviews the exhibition "Alexey Brodovitch: Astonish Me" by artist Alexey Brodovitch that was held at the Barnes Foundation in Philadelphia, Pennsylvania from March 3 to May 19, 2024.

The aim of this essay is to give a high-level overview of Irenaeus’s beatific vision, and to suggest that for him, the beatific vision has a temporal dimension (now and future) and a dimension of degree (lesser now, greater in the future). His beatific vision is witnessed as it intersects with at least four main ideas in his writing—the Trinity, anthropology, resurrection, and his eschatology. Irenaeus famously held that ‘the glory of God is living man, and the life of man is the vision of God’ (AH 4.20.7), which speaks to the reality of seeing God in the present, but he could also look forward in anticipation to beholding the face of God in the resurrected body in the new creation. What made the latter possible is the gradual beholding of God in the present that makes one prepared to see God’s glory in the future. Additionally, the visio Dei is Trinitarian. We behold God in Christ, since God the Father is invisible, and it is the Holy Spirit who prepares us incrementally to see God.