Model checking coalitional games in shortage resource scenarios

Verification of multi-agents systems (MAS) has been recently studied taking into account the need of expressing resource bounds. Several logics for specifying properties of MAS have been presented in quite a variety of scenarios with bounded resources. In this paper, we study a different formalism, called Priced Resource-Bounded Alternating-time Temporal Logic (PRBATL), whose main novelty consists in moving the notion of resources from a syntactic level (part of the formula) to a semantic one (part of the model). This allows us to track the evolution of the resource availability along the computations and provides us with a formalisms capable to model a number of real-world scenarios. Two relevant aspects are the notion of global availability of the resources on the market, that are shared by the agents, and the notion of price of resources, depending on their availability. In a previous work of ours, an initial step towards this new formalism was introduced, along with an EXPTIME algorithm for the model checking problem. In this paper we better analyze the features of the proposed formalism, also in comparison with previous approaches. The main technical contribution is the proof of the EXPTIME-hardness of the the model checking problem for PRBATL, based on a reduction from the acceptance problem for Linearly-Bounded Alternating Turing Machines. In particular, since the problem has multiple parameters, we show two fixed-parameter reductions.Comment: In Proceedings GandALF 2013, arXiv:1307.416

Poising and connectivity of enhancers upon naïve-to-primed transition in human embryonic stem cells (hESCs)

Enhancers are non-coding DNAelements that play crucial roles in transcriptional control, particularly in development. Patterns of histone modifications at enhancers are commonly used to infer their activity states and, poised enhancers (PEs) in particular display a ’bivalent’ chromatin state: the ’active’ H3K4me1 and the ’repressive’, Polycombassociated H3K27me3. Typically observed in pluripotent stem cells (PSCs), it was shown that PEs are required for gene activation later during differentiation. However, the function of the poised state of enhancers remains largely unknown. To trace the emergence of PEs in early development, I have extensively optimized a recently developed low-cell number Capture Hi-C protocol to perform Poised Enhancer Capture Hi-C (PECHi-C) in PSCs, in time course upon the naïve-to-primed transition, which is known to associate with a major shift in the localisation of Polycomb proteins, from a broader to a highly focal pattern. PECHi-C revealed that the PE-mediated regulatory circuitry undergoes significant reorganization between the two states. In particular, I detected three predominant patterns of PE-mediated interactions: the UP, DOWN and CONSTANT interaction classes. Integrating these results with Cut&Tag data on histone modifications revealed an interplay between the acquisition of the poised state at enhancers and their interaction dynamics whereby, at least in some cases, the acquisition of the bivalent signature occurs in parallel to the acquisition of their contacts. Moreover, the analyses suggested that day 3 of the transition is a pivotal point of the naïve-to-primed transition for the emergence of PEs. Overall, this thesis provided further insights into the emergence of PE-mediated regulatory circuitry during early embryogenesis. The different patterns of PE connectivity suggest the presence of diverse regulatory mechanisms of PEs, further suggesting that PEs might play a role at earlier stages of embryogenesis, by ensuring the correct transition from the ground state of pluripotency to the primed state.Open Acces

Interpretations of Progressive Education: A Comparative Study of the Philosophies of Education of the Municipal Early Childhood Schools of Reggio Emilia and the Bank Street College of Education

Compares the progressive philosophies of education of the municipal infant-toddler centers and preprimary schools of Reggio Emilia, and Bank Street College of Education and its School for Children. The histories and theoretical origins of each philosophy of education are introduced. Elaborations on the fundamental principles of each are provided, including discussions of the creation of learning environments, the perception of children\u27s learning, the roles of teachers, and the place of the community. Throughout the text, cultural frameworks are made evident, in order to reflect on the influence that culture and history have on the ways in which progressive philosophies of education take form

Proving Continuity of Coinductive Global Bisimulation Distances: A Never Ending Story

We have developed a notion of global bisimulation distance between processes which goes somehow beyond the notions of bisimulation distance already existing in the literature, mainly based on bisimulation games. Our proposal is based on the cost of transformations: how much we need to modify one of the compared processes to obtain the other. Our original definition only covered finite processes, but a coinductive approach allows us to extend it to cover infinite but finitary trees. After having shown many interesting properties of our distance, it was our intention to prove continuity with respect to projections, but unfortunately the issue remains open. Nonetheless, we have obtained several partial results that are presented in this paper.Comment: In Proceedings PROLE 2015, arXiv:1512.0617

Experimental investigation of the productivity of a wet separation process of traditional and bio-plastics

The separation process within a mechanical recycling plant plays a major role in the context of the production of high-quality secondary raw materials and the reduction of extensive waste disposal in landfills. Traditional plants for plastic separation employ dry or wet processes that rely on the different physical properties among the polymers. The hydraulic separator is a device employing a wet technology for particle separation. It allows the separation of two-polymer mixtures into two products, one collected within the instrument and the other one expelled through its outlet ducts. Apparatus performance were analyzed as a function of fluid and solid flow rates, flow patterns developing within the apparatus, in addition to the density, shape, and size of the polymers. For the hydraulic configurations tested, a two-way coupling takes place where the fluid exerts an influence on the plastic particles and the opposite occurs too. The interaction between the solid and liquid phases determines whether a certain polymer settles within the device or is expelled from the apparatus. Tests carried out with samples of increasing volumes of solid particles demonstrate that there are no significant differences in the apparatus effectiveness as far as a two-way interaction takes place. Almost pure concentrates of Polyethylene Terephthalate (PET), Polyvinyl Chloride (PVC), and Polycarbonate (PC) can be obtained from a mixture of traditional polymers. Tests conducted on Polylactic Acid (PLA) and Mater-Bi® samples showed that the hydraulic separator can be effectively employed to separate bio-plastics from conventional plastics with remarkable grade and recovery

Parity-energy ATL for Qualitative and Quantitative Reasoning in MAS

In this paper, we introduce a new logic suitable to reason about strategic abilities of multi-agent systems where (teams of) agents are subject to qualitative (parity) and quantitative (energy) constraints and where goals are represented, as usual, by means of temporal properties. We formally define such a logic, named parity-energy-atl (peatl, for short), and we study its model checking problem, which we prove to be decidable with different complexity upper bounds, depending on different choices for the energy range

Bounding the mass of ultralight bosonic Dark Matter particles with the motion of the S2 star around Sgr A*

Dark matter is undoubtedly one of the fundamental, albeit unknown, components of the standard cosmological model. The failure to detect WIMPs, the most promising candidate particle for cold dark matter, actually opens the way for the exploration of viable alternatives, of which ultralight bosonic particles with masses $\sim 10^{-21}$ eV represent one of the most encouraging. Numerical simulations have shown that such particles form solitonic cores in the innermost parts of virialized galactic halos that are supported by internal quantum pressure on characteristic $\sim$kpc de Broglie scales. In the Galaxy, this halo region can be probed by means of S-stars orbiting the supermassive black hole Sagittarius A* to unveil the presence of such a solitonic core and, ultimately, to bound the boson mass $m_\psi$. Employing a Monte Carlo Markov Chain algorithm, we compare the predicted orbital motion of S2 with publicly available data and set an upper bound $m_\psi \lesssim 3.2\times 10^{-19}$ eV on the boson mass, at 95 \% confidence level. When combined with other galactic and cosmological probes, our constraints help to reduce the allowed range of the bosonic mass to $(2.0 \lesssim m_\psi \lesssim 32.2)\times 10^{-20}$ eV, at the 95 \% confidence level, which opens the way to precision measurements of the mass of the ultralight bosonic dark matter.Comment: 6 pages, 2 figures, 1 table. Accepted for publication on PRD. Additional plot and related code at http://produccioncientifica.usal.es/datos/6464bdb7a842f677be8feeb

Shutting the allowed mass range of the ultralight bosons with S2 star

It is well known that N-body simulations of ultralight bosons show the formation of a solitonic dark matter core in the innermost part of the halo. The scale length of such a soliton depends on the inverse of the mass of the boson. On the other hand, the orbital motion of stars in the Galactic Center depends on the distribution of matter whether be it baryonic or dark, providing an excellent probe for the gravitational field of the region. In this Letter we propose the S-stars in the Galactic Center as a new observational tool, complementary to other astrophysical systems, to narrow down the range of allowed values for an ultralight dark matter candidate boson mass. We built mock catalogs mirroring the forthcoming astrometric and spectroscopic observations of S2, and we used a MCMC analysis to predict the accuracy down to which the mass of an ultralight boson may be bounded, and we showed that, once complementary constraints are considered, this analysis will help to restrict the allowed range of the boson mass. Our analysis forecasts the bound on the mass of an ultralight boson to be $< 10^{-19}$ eV at the 95% of confidence level.Comment: 5 pages, 2 figures, 1 table, 5 appendices. Accepted for publication in A&A Letter

Sustaining the Spindle Assembly Checkpoint to improve cancer therapy

To prevent chromosome segregation errors, the spindle assembly checkpoint (SAC) delays mitosis exit until proper spindle assembly. We found that the FCP1 phosphatase and its downstream target WEE1 kinase oppose the SAC, promoting mitosis exit despite malformed spindles. We further showed that targeting this pathway might be useful for cancer therapy