Symbiogenesis as a driving force of evolution: The legacy of Boris Kozo-Polyansky.

We analyze evolutionary views of Boris Kozo-Polyansky (1890-1957) who was the first who formulated the symbiotic theory of evolution as a concept in his book, Symbiogenesis: A New Principle of Evolution (1924). Later, starting from 1967, Lynn Margulis independently formulated and further developed the concept of symbiogenesis. Although the ideas on the symbiotic origin of chloroplasts and mitochondria appeared earlier, the book of Kozo-Polyansky presented symbiogenesis as the main factor of complexification in the course of evolution, not only in relation to the origin of eukaryotic cell. Kozo-Polyansky incorporated the ideas of symbiogenesis into a broader paradigm that anticipated the important concepts of the modern Extended Evolutionary Synthesis such as the idea of net of life, the evolutionary role of apoptosis, the ideas of punctuated equilibrium, and the concept of metasystem transition.

Single variable defined technology control of the optical properties in MoS2 films with controlled number of 2D-layers.

Fabrication of practical devices based on the transient metal dichalcogenides (TMDs) can be successively extended to various areas of the applications if the large area growth technology can be intentionally controlled and the characteristics of the layers can be easily predicted. In present work we presented the principles of the technology control based on the single key variable that can be directly related to the sequence of the technological processes. The atomically thin MoS2 layers were used as a model material and the layers were obtained by the CVD synthesis of the molybdenum precursor. Our thorough study demonstrated that the method allowed to deliberately choose the number of the MoS2 two-dimensional (2D)-layers between 1 and 10 by simply choosing the precursor deposition time. The optical properties of the layers were characterised by the optical transitions that corresponded to the known band structure of the MoS2 layers. Fused calibration diagram was proposed as the practical tool for the technology control and it was proved to be highly successive in relating the 2D-properties of the films with the initial stage of the fabrication technology. The method can be adapted to the wafer size TMDs growth on the diverse substrates.