Interactions and magnetization reversal of Ni nanowires arrays have been investigated by the first order reversal curve (FORC) method. Several series of samples with controlled spatial distribution were considered including simple wires of different lengths and diameters (70 nm and 110 nm) and complex wires with single modulated diameter along their length. Subtle features of magnetic interactions are revealed through a quantitative analysis of the local interaction field profile distributions obtained from FORC. In addition the FORC analysis indicates that the nanowire systems with a mean diameter of 70 nm appear to be organized in symmetric clusters indicative of a reversal-field memory effect.

We report on the effect of hydrostatic pressure on the electrical conductivity and dielectric permittivity of the [Fe(Htrz)(trz)](BF) (Htrz = 1H-1,2,4,-triazole) spin crossover complex. Variable-temperature and -pressure broad-band impedance spectrometry revealed a piezoresistive effect of more than 1 order of magnitude for pressures as low as 500 bar, associated with a large pressure-induced hysteresis of 1700 bar. The origin of the piezoresistive effect has been attributed to the pressure-induced spin state switching in the complex, and the associated P,T phase diagram was determined.

Dynamic covalent polymers are materials formed by reversible covalent bonds and non-covalent interactions through an adaptive constitutional dynamic chemistry. The implementation of dynamic covalent polymers in gene delivery has recently...

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Dynamic constitutional frameworks (DCFs) were synthesized and screened for biofilm inhibition or disruption. They are composed of at rialdehyde core reversibly linked to adiamine PEG connector and to avariety of neutral, anionic, or cationic heads,t og enerate al ibrary of DCFs to generate multivalent dendritic architectures in the presence of Pseudomonas aeruginosa and Staphylococcus aureus.The best DCFs were always polycationic and the nature of the cationic heads significantly impact the antibiofilm activity.T he best antibiofilm activity was observed for DCF3B,displaying ap olyethyleneimine head. As imple inactive guanidinium functional head strongly inhibited biofilm growth when assayed as amultivalent DCF3C.Using amore advanced in vitro biofilm model of chronic wound infection, DCF3C was found significantly superior than all other DCFs.T hese results demonstrate the versatility and effectiveness of DCFs as low cost and efficient systems for antibiofilm disruption.

Pseudomonas aeruginosa is a human pathogen belonging to the top priorities for the discovery of new therapeutic solutions. Its propensity to generate biofilms strongly complicates the treatments required to cure P. aeruginosa infections. Herein we describe the synthesis of a series of novel rotaxanes comprised of a central galactosylated pillar [5]arene, a tetrafucosylated dendron and a tetra-guanidinium subunit. Strategically, we exploited a supramolecular assembly technology to generate complex rotaxanes from relatively simple subcomponents. The final glycorotaxanes displayed high affinity for the two P. aeruginosa lectins LecA and LecB as evaluated by Isothermal Titration Calorimetry. Potent inhibition levels of P. aeruginosa biofilm growth were evidenced showing that the three subunits of the glycorotaxanes work synergistically. Such antibiofilm potency had rarely been reached in the literature. Importantly, none of the final rotaxanes was bactericidal, showing that their antibiofilm activity is lectinmediated but does not depend on bacteria killing, which is a rare feature for antibiofilm agents.

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We studied the effect of a non-hydrostatic pressure on the hysteretic spin crossover in coordination complexes.By introducing into an Ising-like model a double distribution of the interactions and gap energy, respectively, we were able to generate the major hysteresis loop and the FORC diagram for spin-crossover systems of 10 6 hysterons (like-spin domains). We show that, for high pressure gradients around the spin-crossover system, the thermal hysteresis loop takes an asymmetric shape, in good agreement with the experimental data on pressure effect recorded at low temperatures, below the solidification of the pressure transmitting medium. Interestingly, the FORC diagram method seems to be much more sensitive to local changes than the "bulk" parameters, which characterize the major hysteresis loop.