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The interaction between drug carrier and drug molecules is fundamental for the study of drug delivery, drug targeting, and drug release. Until now, little has been known about the interaction at the molecular level. X-Ray absorption near edge structure (XANES) spectroscopy is a sensitive tool for identifying this interaction. Herein, we report the use of calcium and silicon K-edge X-ray absorption near edge structure (XANES) spectroscopy to investigate how drug molecules interact with different functional groups in calcium silicate hydrate and anhydrous calcium silicate nanocarriers with different morphologies. Significant changes are observed in the XANES spectra after drug loading; ibuprofen (IBU) loading leads to the ordering of silicates locally and there is loss of hydrates during the IBU loading processes.

Environmentally induced phenotypic plasticity is thought to play an important role in the adaption of plant populations to heterogeneous habitat conditions, and yet the importance of epigenetic variation as a mechanism of adaptive plasticity in natural plant populations still merits further research. In this study, we investigated populations of Vitex negundo var. heterophylla (Chinese chastetree) from adjacent habitat types at seven sampling sites. Using several functional traits, we detected a significant differentiation between habitat types. With amplified fragment length polymorphisms (AFLP) and methylation‐sensitive AFLP (MSAP), we found relatively high levels of genetic and epigenetic diversity but very low genetic and epigenetic differences between habitats within sites. Bayesian clustering showed a remarkable habitat‐related differentiation and more genetic loci associated with the habitat type than epigenetic, suggesting that the adaptation to the habitat is genetically based. However, we did not find any significant correlation between genetic or epigenetic variation and habitat using simple and partial Mantel tests. Moreover, we found no correlation between genetic and ecologically relevant phenotypic variation and a significant correlation between epigenetic and phenotypic variation. Although we did not find any direct relationship between epigenetic variation and habitat environment, our findings suggest that epigenetic variation may complement genetic variation as a source of functional phenotypic diversity associated with adaptation to the heterogeneous habitat in natural plant populations.

Using 2D XANES-XEOL spectroscopy, it is found that the band gap emission of ZnO nanowire arrays is substantially enhanced i.e. that the intensity ratio between the band gap and defect emissions increases by more than an order of magnitude when the excitation energy is scanned across the O K-edge. Possible mechanisms are discussed.