Persistent discrepancies in orbital morphology after surgical treatment of unicoronal craniosynostosis: a critical image-based analysis.

Objective: Unicoronal craniosynostosis (UCS) is characterized by complex orbital deformity and is typically treated by asymmetrical fronto-orbital remodeling (FOR) during the 1st year of life. The aim of this study was to elucidate to what extent orbital morphology is corrected by surgical treatment.

Methods: The extent to which orbital morphology was corrected by surgical treatment was tested by analysis of differences in volume and shape between synostotic, nonsynostotic, and control orbits at two time points.

High-resolution X-ray absorption spectroscopy as a probe of crystal-field and covalency effects in actinide compounds.

Applying the high-energy resolution fluorescence-detection (HERFD) mode of X-ray absorption spectroscopy (XAS), we were able to probe, for the first time to our knowledge, the crystalline electric field (CEF) splittings of the [Formula: see text] shell directly in the HERFD-XAS spectra of actinides. Using ThO2 as an example, data measured at the Th 3d edge were interpreted within the framework of the Anderson impurity model. Because the charge-transfer satellites were also resolved in the HERFD-XAS spectra, the analysis of these satellites revealed that ThO2 is not an ionic compound as previously believed.

Local Symmetry Effects in Actinide 4f X-ray Absorption in Oxides.

A systematic X-ray absorption study at actinide N6,7 (4f → 6d transitions) edges was performed for light-actinide oxides including data obtained for the first time for NpO2, PuO2, and UO3. The measurements were supported by ab initio calculations based on local-density-approximation with added 5f-5f Coulomb interaction (LDA+U). Improved energy resolution compared to common experiments at actinide L(2,3) (2p → 6d transitions) edges allowed us to resolve the major structures of the unoccupied 6d density of states (DOS) and estimate the crystal-field splittings in the 6d shell directly from the spectra of light-actinide dioxides.

Sensitivity to actinide doping of uranium compounds by resonant inelastic X-ray scattering at uranium L3 edge.

Valence-to-core resonant inelastic X-ray scattering (RIXS) and high energy resolution fluorescence detection (HERFD) X-ray absorption measurements were performed at the U L3 edges of UO2 and UO2(NO3)2(H2O)6. The results are compared with model calculations based on the local-density-approximation formalism, taking into account Coulomb interaction U (LDA + U). We show that despite strong 5f-5f electronic correlations in the studied systems and the use of core-level excitations in the intermediate stage of the spectroscopic process, the RIXS technique probes a convolution of the single-particle densities of states in the valence and conduction bands.