Several studies have reported glacial refugia and migration pathways for different pine species in the Iberian Peninsula, all of them based on a single-species approach. In this paper, chloroplast microsatellites (cpSSRs) are used to compare population genetic structure and diversity estimates for interspecific pairs of populations located along a cline from southwestern (latitude 36 ° 32 ′ N, longitude 5 ° 17 ′ W) to northeastern Spain (latitude 42 ° 14 ′ N, longitude 2 ° 47 ′ E) in two widely distributed Mediterranean pines, Pinus halepensis Mill. and Pinus pinaster Ait. Some cpSSRs were shared between species, facilitating comparison of levels of gene diversity at the species level and inferences about within and among species differentiation. P. pinaster showed a much higher number of variants (29) and haplotypes (69) than P. halepensis (20 and 21, respectively). Moreover, genetic diversity estimates for interspecific pairs of populations along the cline were negatively correlated. Three main causes may explain the differences between species in the present-day distribution of genetic diversity: (1) the distribution of genetic variability before the Quaternary glaciations, with an earlier presence of P. pinaster in the Iberian Peninsula and a late spread of P. halepensis from eastern and central Europe, (2) the location of the Holocene glacial refugia and the migration pathways from these refugia to the present-day range (from northeast to southwest in P. halepensis and from southwest to northeast and northwest in P. pinaster ) and (3) the interactions between species during the postglacial spread.

The Canary archipelago, located on the northwestern Atlantic coast of Africa, is comprised of seven islands aligned from east to west, plus seven minor islets. All the islands were formed by volcanic eruptions and their geological history is well documented providing a historical framework to study colonization events. The Canary Island pine ( Pinus canariensis C. Sm.), nowadays restricted to the westernmost Canary Islands (Gran Canaria, Tenerife, La Gomera, La Palma and El Hierro), is considered an old (Lower Cretaceous) relic from an ancient Mediterranean evolutionary centre. Twenty seven chloroplast haplotypes were found in Canary Island pine but only one of them was common to all populations. The distribution of haplotypic variation in P. canariensis suggested the colonization of western Canary Islands from a single continental source located close to the Mediterranean Basin. Present-day populations of Canary Island pine retain levels of genetic diversity equivalent to those found in Mediterranean continental pine species, Pinus pinaster and Pinus halepensis. A hierarchical analysis of variance (AMOVA) showed high differentiation among populations within islands (approximately 19%) but no differentiation among islands. Simple differentiation models such as isolation by distance or stepping-stone colonization from older to younger islands were rejected based on product-moment correlations between pairwise genetic distances and both geographic distances and population-age divergences. However, the distribution of cpSSR diversity within the islands of Tenerife and Gran Canaria pointed towards the importance of the role played by regional Pliocene and Quaternary volcanic activity and long-distance gene flow in shaping the population genetic structure of the Canary Island pine. Therefore, conservation strategies at the population level are strongly recommended for this species.

Vacancy-ordered double perovskites Cs₂SnX₆ (X = Cl, Br, I) have emerged as promising lead-free and ambient-stable materials for photovoltaic and optoelectronic applications. To advance these promising materials, it is crucial to determine the correlations between physical properties and their local structure and dynamics. Solid-state NMR spectroscopy of multiple NMR-active nuclei (¹³³Cs, ¹¹⁹Sn and ³⁵Cl) in these cesium tin(IV) halides has been used to decode the structure, which plays a key role in the materials’ optical properties. The ¹¹⁹Sn NMR chemical shifts span approximately 4000 ppm and the ¹¹⁹Sn spin-lattice relaxation times span three orders of magnitude when the halogen goes from chlorine to iodine in these diamagnetic compounds. Moreover, ultrawideline ³⁵Cl NMR spectroscopy for Cs₂SnCl₆ indicates an axially symmetric chlorine electric field gradient tensor with a large quadrupolar coupling constant of <i>ca.</i> 32 MHz, suggesting a chlorine that is directly attached to Sn(IV) ions. Variable temperature ¹¹⁹Sn spin lattice relaxation time measurements uncover the presence of hidden dynamics of octahedral SnI₆ units in Cs₂SnI₆ with a low activation energy barrier of 12.45 kJ/mol (0.129 eV). We further show that complete mixed-halide solid solutions of Cs₂SnCl_xBr_6−x and Cs₂SnBr_xI_6−x (0 ≤ x ≤ 6) form at any halogen compositional ratio. ¹¹⁹Sn and ¹³³Cs NMR spectroscopy resolve the unique local SnCl<i>_n</i>Br_6−<i>n</i>and SnBr<i>_n</i>I_6−<i>n</i> (<i>n</i> = 0−6) octahedral and CsBr<i>_m</i>I_{12−<i>m</i>} (<i>m</i> = 0−12) cuboctahedral environments in the mixed-halide samples. The experimentally observed ¹¹⁹Sn NMR results are consistent with magnetic shielding parameters obtained by density functional theory computations to verify random halogen distribution in mixed-halide analogues. Finally, we demonstrate the difference in the local structures and optical absorption properties of Cs₂SnI₆ samples prepared by solvent-assisted and solvent-free synthesis routes.

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Quercus suber L. is a Mediterranean forest species with ecological, social and economic value. Clonal propagation of Q. suber elite trees has been successfully obtained from in vitro-derived somatic and gametic embryos. These clonal lines play a main role in breeding and genetic studies of Q. suber. To aid in unravelling diverse genetic and biological unknowns, a proteomic approach is proposed. The proteomic analysis of Q. suber somatic and gametic in vitro culture-derived embryos, based on DIGE and MALDI-MS, has produced for the first time proteomic data on this species. Seventeen differentially expressed proteins have been identified which display significantly altered levels between gametic and somatic embryos. These proteins are involved in a variety of cellular processes, most of which had been neither previously associated with embryo development nor identified in the genus Quercus. Some of these proteins are involved in stress and pollen development and others play a role in the metabolism of tannins and phenylpropanoids, which represent two of the major pathways for the synthesis of cork chemical components. Furthermore, the augmented expression levels found for specific proteins are probably related to the homozygous state of a doubled-haploid sample. Proteins involved in synthesis of cork components can be detected at such early stages of development, showing the potential of the method to be useful in searching for biomarkers related to cork quality.