On Predicting Mössbauer Parameters of Iron-Containing Molecules with Density-Functional Theory

The performance of six frequently used density functional theory (DFT) methods (RPBE, OLYP, TPSS, B3LYP, B3LYP*, and TPSSh) in the prediction of Mössbauer isomer shifts(δ) and quadrupole splittings (ΔEQ) is studied for an extended and diverse set of Fe complexes. In addition to the influence of the applied density functional and the type of the basis set, the effect of the environment of the molecule, approximated with the conducting-like screening solvation model (COSMO) on the computed Mössbauer parameters, is also investigated. For the isomer shifts the COSMO-B3LYP method is found to provide accurate δ values for all 66 investigated complexes, with a mean absolute error (MAE) of 0.05 mm s–1 and a maximum deviation of 0.12 mm s–1. Obtaining accurate ΔEQ values presents a bigger challenge; however, with the selection of an appropriate DFT method, a reasonable agreement can be achieved between experiment and theory. Identifying the various chemical classes of compounds that need different treatment allowed us to construct a recipe for ΔEQ calculations; the application of this approach yields a MAE of 0.12 mm s–1 (7% error) and a maximum deviation of 0.55 mm s–1 (17% error). This accuracy should be sufficient for most chemical problems that concern Fe complexes. Furthermore, the reliability of the DFT approach is verified by extending the investigation to chemically relevant case studies which include geometric isomerism, phase transitions induced by variations of the electronic structure (e.g., spin crossover and inversion of the orbital ground state), and the description of electronically degenerate triplet and quintet states. Finally, the immense and often unexploited potential of utilizing the sign of the ΔEQ in characterizing distortions or in identifying the appropriate electronic state at the assignment of the spectral lines is also shown

Political Economy of Civil Society

This chapter explores the role of civil society in relation to the economy and the polity by focusing on three distinct yet related dimensions: (1) the conceptual history of civil society in relation to political economy; (2) the theory underpinning a political economy of civil society; (3) the implications of a political economy of civil society for policy-making. The main argument is that there is a fundamental difference between ancient and medieval conceptions, which emphasise natural sociability, and modern accounts that accentuate a violent ‘state of nature’. As a result, civil society either reflects the fundamental embeddedness of economic and political processes in social relations or is an artificial construct. The chapter develops a typology of four modern models, provides a theory of the political economy of civil society and outlines a series of policy ideas

Gardens of happiness: Sir William Temple, temperance and China

This is the author accepted manuscript. The final version is available from Taylor & Francis via the DOI in this recordSir William Temple, an English statesman and humanist, wrote “Upon the Gardens of Epicurus” in 1685, taking a neo-epicurean approach to happiness and temperance. In accord with Pierre Gassendi’s epicureanism, “happiness” is characterised as freedom from disturbance and pain in mind and body, whereas “temperance” means following nature (Providence and one’s physiopsychological constitution). For Temple, cultivating fruit trees in his garden was analogous to the threefold cultivation of temperance as a virtue in the humoral body (as food), the mind (as freedom from the passions), and the bodyeconomic (as circulating goods) in order to attain happiness. A regimen that was supposed to cure the malaise of Restoration amidst a crisis of unbridled passions, this threefold cultivation of temperance underlines Temple’s reception of China and Confucianism wherein happiness and temperance are highlighted. Thus Temple’s “gardens of happiness” represent not only a reinterpretation of classical ideas, but also his dialogue with China.European CommissionLeverhulme Trus

Use of fluorescence in situ hybridization as a tool for introgression analysis and chromosome identification in coffee (Coffea arabica L.)

Fluorescence in situ hybridization (FISH) was used to study the presence of alien chromatin in interspecific hybrids and one introgressed line (S.288) derived from crosses between the cultivated species Coffea arabica and the diploid relatives C canephora and C. liberica. In situ hybridization using genomic DNA from C. canephora and C. arabica as probes showed elevated cross hybridization along the hybrid genome, confirming the weak differentiation between parental genomes. According to our genomic in situ hybridization (GISH) data, the observed genomic resemblance between the modern C. canephora genome (C) and the C. canephora-derived subgenome of C. arabica (C-a) appears rather considerable. Poor discrimination between C and Ca chromosomes supports the idea of low structural modifications of both genomes since the C. arabica speciation, at least in the frequency and distribution of repetitive sequences. GISH was also used to identify alien chromatin segments on chromosome spreads of a C liberica-introgressed line of C arabica. Further, use of GISH together with BAC-FISH analysis gave us additional valuable information about the physical localization of the C. liberica fragments carrying the S(H)3 factor involved in resistance to the coffee leaf rust. Overall, our results illustrate that FISH analysis is a complementary tool for molecular cytogenetic studies in coffee, providing rapid localization of either specific chromosomes or alien chromatin in introgressed genotypes derived from diploid species displaying substantial genomic differentiation from C. arabica

Three-dimensional spectral measurements of paint samples using optical coherence tomography

The visual appearance of a painting is the result of variations in pigments, layers and layer thicknesses. An important role can be played by ground colour. The ground is the first preparation of the support before the actual painting. Medieval painters worked on white grounds. Coloured grounds appeared during the late 15th century in Italy before spreading to the northern part of Europe around 1550. Painters like Rembrandt or Rubens exploited dark or light coloured grounds to create spectacular, realistic effects. But how can we understand how they do this? To answer this question and add some quantifiable analysis, one needs to resolve the spectral reflectivity profile of a painting in three spatial dimensions. In addition, as the main intent is to relate the optical effects with colours, one needs to operate using visible light. The answer to these challenges is visible-light Optical Coherence Tomography (vis-OCT). In this study, we investigate the use of vis-OCT to measure the reflectivity profile of multi-layered paint samples in three dimensions. Using mock-up paint samples we prepared with two thin paint layers on a black and a white paper support, we measured the reflectivity profiles of the separate colours and of the superposed colours over either the black or white (back)ground. This paper first describes the signal processing involved in rebuilding the spectral reflectivity in three dimensions. Secondly, we will present the results obtained from the mock-up samples and draw conclusions on the possibility to discriminate colours in a three-dimensional context. All reflectivity measurements will be compared to a classical, commercially available hyperspectral imaging setup. This study is executed in the context of the NWO Down to the Ground Project. The results of the OCT measurements will be used by technical art historians and conservators for investigations into coloured grounds