Microcompartmentalization is a crucial step in the origin of life. More than 30 years ago, Oparin et al. proposed models based on biochemical reactions taking place in so-called coacervates. Their intention was to develop systems with which semipermeable microcompartments could be established. In the present work we follow their intuition, but we use well-characterized bilayer structures instead of the poorly characterized coacervates. Liposomes from phospholipids can be used as microreactors but they exhibit only a modest permeability and, therefore, chemical reactions occurring inside these structures are depleted after a relatively short period. Here it is shown that even highly stable liposomes from 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphocholine (POPC) can be used as semipermeable microreactors when treated with sodium cholate. Using this kind of mixed liposomes, we describe a biochemical reaction occurring inside the liposomes while the same reaction is prevented in the external medium. In addition, we show that this cholate-induced permeability of POPC bilayers can even be used to load macromolecules such as enzymes from the outside.

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In this paper, I address the problem of auxiliary selection in Standard Italian and in Southern Italo-Romance varieties. In the former, the auxiliary depends on the argument structure, in the latter on the person feature of the subject. However, the features of the arguments play a crucial role even in languages where auxiliary selection is argument structure- driven. Therefore, I propose that auxiliary selection is the result of person Agree in both systems. Cross-linguistic variation is due to a single syntactic parameter (the ordering of the features on Perf) and to different inventories of vocabulary entries. In this contribution, I focus on Italo-Romance varieties, in particular on person-driven systems and on so-called mixed systems. I show that the apparently very different systems of auxiliary selection in Standard Italian and in Italo-Romance varieties are more similar than it seems: not only auxiliary selection in Italian is Agree for the person feature, but also many alleged person-driven varieties are indeed argument-structure-based systems.