According to Clausius formulation of the second law of thermodynamics, for any thermal machine withdrawing heats Q1,2 from two heat reservoirs at temperatures T1,2, it holds Q1/T1 + Q2/T2 ≤ 0. Combined with the observation that the quantity Q1 + Q2 is the work W done by the system, that inequality tells that only 4 possible operation modes are possible for the thermal machine, namely heat engine [E], refrigerator [R], thermal accelerator [A] and heater [H]. We illustrate their emergence in the finite time operation of a quantum Otto engine realised with a single qubit. We first focus on the ideal case when isothermal and thermally-insulated strokes are well separated, and give general results as well as results pertaining to the specific finite-time Landau-Zener dynamics. We then present realistic results pertaining to the solid-state experimental implementation proposed by Karimi and Pekola [Phys. Rev. B 94 (2016) 184503]. That device is non-adiabatic both in the quantum mechanical sense and in the thermodynamical sense. Oscillations in the power extracted from the baths due to coherent LZ tunnelling at too low temperatures are observed that might hinder the robustness of the operation of the device against experimental noise on the control parameters.

The scenic plaza mayor shares with the theater organisms some formative characters, since they both derive from a transformation, by knotting, of pre-existing buildings and fabrics. This architectural transformation is generated, at the beginning, by a change in the modalities of using public space. As for the corral de comedias, the process is due to the sedentarization of the theatrical practice, which abandons the itinerant dimension of the street to move inside the buildings (such as private homes and palaces). The original corral de comedias was in fact set up inside an open place that could be covered, and this feature became permanent  over time, creating a new building type. Similarly, since the sixteenth century,  squares became the fundamental location of Spanish civic life as well as they hosted all sorts of political, religious and festive representations, but also the venue of executions. For this purpose, namely to allow people to watch such events, the squares were transformed, by raising temporary walls and walkways. In some cases, like Tembleque and San Carlos del Valle, they began to realize permanent continuous balconies, with solutions that seem to have followed the same morphological evolution of corrales de comedias. In both cases it was necessary to unify different elements (buildings or rooms) and connect them to each other, through a process of “knotting”, in order to create a new organism. Over time the physiognomy of the spaces, originally open,  assumed the permanent characters of a new type, closed and similar to the courtyard of a “palazzo”.

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