Correction to: Foreword to the memorial issue for Professor Roberto Marassi

Journal of Solid State Electrochemistry -     

New insights into the seleniranium ion promoted cyclization of prenyl and propenylbenzene aryl ethers

The chromane core is widely represented in nature being part of a wide array of secondary metabolites of plant, fungal, and bacterial origin. In this paper an improved method for the chemical synthesis of differently substituted chromanes is described. Substituted 2H-1-benzopyrans have been synthesized in good to excellent yields (52–81%) by treatment of 3,3-dimethylallyl and propenylbenzene ethers of differently substituted phenols with phenylselenyl chloride.     

Evidence for Multiple Binding Modes in the Initial Contact Between SARS-CoV-2 Spike S1 Protein and Cell Surface Glycans**

Infection of host cells by SARS-CoV-2 begins with recognition by the virus S (spike) protein of cell surface heparan sulfate (HS), tethering the virus to the extracellular matrix environment, and causing the subunit S1-RBD to undergo a conformational change into the ‘open’ conformation. These two events promote the binding of S1-RBD to the angiotensin converting enzyme 2 (ACE2) receptor, a preliminary step toward viral-cell membrane fusion. Combining ligand-based NMR spectroscopy with molecular dynamics, oligosaccharide analogues were used to explore the interactions between S1-RBD of SARS CoV-2 and HS, revealing several low-specificity binding modes and previously unidentified potential sites for the binding of extended HS polysaccharide chains. The evidence for multiple binding modes also suggest that highly specific inhibitors will not be optimal against protein S but, rather, diverse HS-based structures, characterized by high affinity and including multi-valent compounds, may be required.     

Convex games with an infinite number of players and sequencing situations

In this paper we study convex games with an infinite countable set of agents and provide characterizations of this class of games. To do so, and in order to overcome some shortcomings related to the difficulty of dealing with infinite orderings, we need to use a continuity property. Infinite sequencing situations where the number of jobs is infinite countable can be related to convex cooperative TU games. It is shown that some allocations turn out to be extreme points of the core of an infinite sequencing game.     

Elliptic near-MDS codes over $${\mathbb{F}}_5$$

Let Γ₆ be the elliptic curve of degree 6 in PG(5, q) arising from a non-singular cubic curve of PG(2, q) via the canonical Veronese embedding

The bargaining set for sharing the power

The evaluation of the power of the parties of a Parliament is usually carried out following a static approach, counting their numbers of seats and possible ideological relations among them. In this paper we propose a dynamic model in which parties may blackmail each other in order to increase their power at the expense of others. This model may be solved in terms of the Bargaining Set (Aumann and Maschler in Advances in game theory. Princeton University Press, Princeton, 1964), a set valued solution, in contrast to the classical power indices that are point valued; so it may be used to check the robustness of a power division taking into account possible blackmailing activities. The paper is mainly based on the idea of proposing an existing instrument, the Bargaining Set, as power index to analyze this blackmailing situation. The computational complexity limits the possibility of applying it to real-world situations, but the possibility of making the computation easier is shown using some examples.     

A characterization of Denniston's maximal arcs

Our main result is the following characterization of Denniston's maximal arcs: If a maximal arcK in PG(2,q),q even, is invariant under a linear collineation group of PG(2,q) which is cyclic and has orderq+1, thenK is a Denniston's maximal arc.This work was partially supported by a grant of M.P.I. (Research project Strutture geometriche combinatorie e loro applicazioni).