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The thermodynamics of black holes is investigated in the case of fractal-like event horizon, initially introduced by Barrow. The nature of the horizon surface is controlled by a parameter 0≤Δ≤1 with 0 corresponding to continuous space and 1 to completely fractal one. It is found that the entropy, the Helmholtz free energy, the mass and the heat capacity of the black hole are altered in the presence of non-zero Δ. As the black hole produces Hawking radiation, the dependence of its mass on time becomes softer as Δ increases, resulting in longer evaporation times. This effect makes relatively small primordial black holes to survive long enough so as to be potential ingredients of cold dark matter. The concept of Barrow-type structure can be generalized to the entire space resulting in a modified space-time metric.

Despite decades of intensive research on bacteriophage lambda, a relatively uncharacterized region remains between the exo and xis genes. Collectively, exo-xis region genes are expressed during the earliest stages of the lytic developmental cycle and are capable of affecting the molecular events associated with the lysogenic-lytic developmental decision. In Shiga toxin-producing E. coli (STEC) and enterohemorragic E. coli (EHEC) that are responsible for food- and water-borne outbreaks throughout the world, there are distinct differences of exo-xis region genes from their counterparts in lambda phage. Together, these differences may help EHEC-specific phage and their bacterial hosts adapt to the complex environment within the human intestine. Only one exo-xis region protein, Ea8.5, has been solved to date. Here, I have used the AlphaFold and RoseTTAFold machine learning algorithms to predict the structures of six exo-xis region proteins from lambda and STEC/EHEC phages. Together, the models suggest possible roles for exo-xis region proteins in transcription and the regulation of RNA polymerase.