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Large brown macroalgae are foundational threatened species in coastal ecosystems from the subtropical northeastern Atlantic, where they have exhibited a drastic decline in recent years. This study describes the potential habitat of Gongolaria abies-marina, its current distribution and conservation status, and the major drivers of population decline. The results show a strong reduction of more than 97% of G. abies-marina populations in the last thirty years and highlight the effects of drivers vary in terms of spatial heterogeneity. A decrease in the frequency of high waves and high human footprint are the principal factors accounting for the long-term decline in G. abies-marina populations. UV radiation and sea surface temperature have an important correlation only in certain locations. Both the methodology and the large amount of data analyzed in this study provide a valuable tool for the conservation and restoration of threatened macroalgae.

A detailed correlative structural, magnetic and chemical analysis of non-stoichiometric cobalt ferrite micrometric crystals was performed by x-ray magnetic circular dichroism combined with photoemission microscopy, low energy electron microscopy, and atomic force microscopy. The vector magnetization at the nanoscale is obtained from magnetic images at different x-ray incidence angles and compared with micromagnetic simulations, revealing the presence of defects which pin the magnetic domain walls. A comparison of different types of defects and the domain walls location suggests that the main source of pinning in these microcrystals are linear structural defects induced in the spinel by the substrate steps underneath the islands.

In pulsed laser deposition, the laser irradiation wavelength and the substrate nature and temperature crucially affect the composition, crystallinity, structure and magnetic properties of the grown deposits. In this work, cobalt ferrite (CoFeO) thin films were deposited on Si (1 0 0) and SrTiO (1 0 0) single crystal substrates at room temperature and 770 K using laser wavelengths of 213, 532 and 1064 nm. The deposited films were characterized by atomic force microscopy to determine the surface morphology, by X-ray diffraction to examine their crystallinity, and by micro-Raman, scanning electron microscopy/energy-dispersive X-ray spectroscopy, X-ray photoelectron and Mössbauer spectroscopies to investigate their composition and stoichiometry. Magnetic characterization was carried out by superconducting quantum interference device magnetometry. At 770 K and 1064 nm, the films consisted of single-crystal CoFeO ((1 0 0) orientation) when grown on SrTiO, and of polycrystalline CoFeO when grown on Si. The composition of the films became more complex at shorter wavelengths as they contained magnetite and other minority phases in different concentrations. The crystalline quality of the films also decreased with decreasing wavelength even including superparamagnetic species. In general, for the same wavelength, the deposits obtained at room temperature were less crystalline than those produced with the substrate heated at 770 K.

© 2016 The Authors. Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license. Conferencia: E-MRS Spring Meeting / Symposium CC on In Situ Studies of Functional Nano Materials at Large Scale Facilities - From Model Systems to Applications (2016. Lille, Francia). This work is supported by the Spanish Ministry of Economy and Competitiveness through Projects No. MAT2015- 64110-C2-1-P, MAT2015-64110-C2-2-P and MAT2013-48009-C4-1-P. These experiments were performed at the CIRCE beamline of the ALBA Synchrotron Light Facility with the collaboration of ALBA staff., Mixed iron-cobalt oxides have been grown on a Ru(0001) single crystal substrate by reactive molecular beam epitaxy. The growth has been followed by low-energy electron microscopy and diffraction. Chemical characterization has been performed by selected area x-ray absorption spectroscopy. As previously known, iron grows into a wetting layer of FeO. In contrast, cobalt grows into three-dimensional islands of CoO, of either with a (111) –most common-or a (100) orientation. For mixed compositions, flat 2D growth is regained. Depending on temperature, either segregation into two FeCo compositions or a single phase is detected. In all cases the structure corresponds to an in-plane expanded (111)-oriented halite one. When only one phase is observed or for the Co-rich phase in the two phase film, its crystal structure is rotated by 30. relative to the Ru substrate, unlike the Co-poor phase which appears aligned with the substrate., Ministerio de Economía y Competitividad (MINECO), Depto. de Física de Materiales, Fac. de Ciencias Físicas, TRUE, pub

Mixed iron-cobalt oxides have been grown on a Ru(0001) single crystal substrate by reactive molecular beam epitaxy. The growth has been followed by low-energy electron microscopy and diffraction. Chemical characterization has been performed by selected area x-ray absorption spectroscopy. As previously known, iron grows into a wetting layer of FeO. In contrast, cobalt grows into three-dimensional islands of CoO, of either with a (111) -most common- or a (100) orientation. For mixed compositions, flat 2D growth is regained. Depending on temperature, either segregation into two FeCo compositions or a single phase is detected. In all cases the structure corresponds to an in-plane expanded (111)-oriented halite one. When only one phase is observed or for the Co-rich phase in the two phase film, its crystal structure is rotated by 30¿ relative to the Ru substrate, unlike the Co-poor phase which appears aligned with the substrate.

We have grown mixed magnetite/cobalt ferrite epitaxial films on SrTiO3 by infrared pulsed-laser deposition. Diffraction experiments indicate epitaxial growth with a relaxed lattice spacing. The films are flat with two distinct island types: nanometric rectangular mounds in two perpendicular orientations, and larger square islands, attributed to the two main components of the film as determined by Mössbauer spectroscopy. The origin of the segregation is suggested to be the oxygen-deficiency during growth.