The postmastectomy pain syndrome: an epidemiological study on the prevalence of chronic pain after surgery for breast cancer

The prevalence of the postmastectomy pain syndrome (PMPS) and its clinical characteristics was assessed in a group of patients who had undergone surgery for breast cancer at the Department of Surgery, Odense University Hospital, within the period of 1 May 2003 to 30 April 2004. The study included 258 patients and a reference group of 774 women. A questionnaire was mailed to the patients 1½ year after surgery and to the women in the reference group. The PMPS was defined as pain located in the area of the surgery or ipsilateral arm, present at least 4 days per week and with an average intensity of at least 3 on a numeric rating scale from 0 to 10. The prevalence of PMPS was found to be 23.9%. The odds ratio of developing PMPS was 2.88 (95% confidence interval 1.84–4.51). Significant risk factors were as follows: having undergone breast surgery earlier (OR 8.12), tumour located in the upper lateral quarter (OR 6.48) and young age (OR 1.04). This study shows that, although recent advances in the diagnostic and surgical procedures have reduced the frequency of the more invasive surgical procedures, there still is a considerable risk of developing PMPS after treatment of breast cancer

Encoding complexity within supramolecular analogues of frustrated magnets

The solid phases of gold(I) and/or silver(I) cyanides are supramolecular assemblies of inorganic polymer chains in which the key structural degrees of freedom—namely, the relative vertical shifts of neighbouring chains—are mathematically equivalent to the phase angles of rotating planar (‘XY’) spins. Here, we show how the supramolecular interactions between chains can be tuned to mimic different magnetic interactions. In this way, the structures of gold(I) and/or silver(I) cyanides reflect the phase behaviour of triangular XY magnets. Complex magnetic states predicted for this family of magnets—including collective spin-vortices of relevance to data storage applications—are realized in the structural chemistry of these cyanide polymers. Our results demonstrate how chemically simple inorganic materials can behave as structural analogues of otherwise inaccessible ‘toy’ spin models and also how the theoretical understanding of those models allows control over collective (‘emergent’) phenomena in supramolecular systems

Ab initio periodic modelling of the vibrational spectra of molecular crystals: the case of uracil

© 2018, Springer-Verlag GmbH Germany, part of Springer Nature. The structure and vibrational spectra of solid uracil have been simulated in the framework of Density Functional Theory (DFT) using a periodic unit cell model. Structural parameters are reproduced reasonably well by using the dispersion corrected, global hybrid Hartree–Fock/DFT functional B3LYP-D* and an all-electron, Gaussian type, triple zeta basis set with polarisation. The periodic calculation provides the full set of fundamental harmonic vibrational modes, whose nature can be investigated by inspecting the corresponding eigenvectors. Accounting for dispersive interactions indirectly affects the spectra, through the impact on the cell parameters. Marked differences are found between the gas and solid phase spectra, that can be related to either mode coupling or direct alteration of the potential energy via neighbour-neighbour molecular interactions. Anharmonicity needs to be considered for a meaningful comparison with experiments; a single scaling factor provides a significantly improved agreement for most of the frequencies, except for the NH stretchings, which require a larger downscaling. This rescaling strategy yields results of comparable quality with respect to previously reported calculations with a cluster model and a perturbative treatment of anharmonicity