Finite size nanoscopic systems are very interesting for being halfway between atoms and bulk systems. In this category molecular magnets play very important role in fundamental physics since these systems have shown new magnetic and electronic futures and revealed to be promising for possible applications in quantum computing and magnetoelectronics. Among these systems, there are homonuclear an...

The photochemistry of three 9-(dihydroxyphenyl)anthracenes 6-8 was studied in neat CH(3)CN and selected organic solvents, to investigate excited state intramolecular proton transfer (ESIPT) from the phenol to the anthracene moiety. In D(2)O-CH(3)CN mixtures, the observed deuterium exchange of 6-8 is consistent with water-mediated (formal) ESIPT process from the ortho phenolic OH to the 10'-posi...

We present evidence for an exotic gapless insulating phase of hard-core bosons on multileg ladders with a density commensurate with the number of legs. In particular, we study in detail a model of bosons moving with direct hopping and frustrating ring exchange on a 3-leg ladder at ν=1/3 filling. For sufficiently large ring exchange, the system is insulating along the ladder but has two gapless ...

In quantum solids composed of fermion particles, such as helium-3 and electrons, the low-temperature physics is governed by spin exchanges, according to the Thouless theory. We present path integral Monte Carlo calculations of ring exchange energies on ‘clean’ two-dimensional crystals of both helium-3 and electrons. We see a remarkable similarity of the results for these two ‘opposite’ systems....

In this paper, we initiate the study of a new class of algebras, which we call cluster algebras. Before giving precise definitions, we present some of the main features of these algebras. For any positive integer n, a cluster algebra A of rank n is a commutative ring with unit and no zero divisors, equipped with a distinguished family of generators called cluster variables. The set of cluster v...

The disulfide dihedral angle in epidithiodiketopiperazines (ETPs) is near 0°. Application of this highest possible ring tension to strain-promoted thiol-mediated uptake results in efficient delivery to the cytosol and nucleus. Compared to the previous best asparagusic acid (AspA), ring-opening disulfide exchange with ETPs occurs more efficiently even with nonactivated thiols, and the resulting ...

This thesis is divided into two distinct parts. The first part of the thesis explores various deniable signature schemes and their applications. Such schemes do not bind a unique public key to a message, but rather specify a set of entities that could have created the signature, so each entity involved in the signature can deny having generated it. The main deniable signature schemes we examine...

In this thesis we focus on implementing an optimized version of Nussbaumer’s negacyclic convolution algorithm for the New Hope key exchange protocol. To do so, we start by discussing the algorithm itself as specified by Knuth and the optimizations that can be applied to lower the amount of ring operations as specified by Nussbaumer. We shall see that the numbertheoretic transform, the alternati...