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HR acknowledges financial support by the China Scholarship Council (CSC; grant nr. 201506400014). EGR acknowledges the support of the Beatriu de Pinós programme of the Government of Catalonia's Secretariat for Universities and Research of the Department of Economy and Knowledge (2016 BP 00208). We thank Bruce Hobbs and an anonymous reviewer for their suggestions to improve this article. ; Peer reviewed ; Postprint

Granite is found in many world heritage monuments and cities. It continues to be one of the most widely used stones in today's construction, given its abundance, uniformity and durability. Quarrymen traditionally cut this rock along its orthogonal slip planes, where splitting is easier. Ranked by ease of splitting, these planes are rift, grain and hardway. Granite is traditionally quarried along the rift plane where coplanar exfoliation microcracks coalesce developing a flat surface. This splitting surface minimizes the cost and effort of subsequent hewing. Rift plane was predominantly used on the fair face of ashlars in heritage buildings worldwide. Determining the petrographic and petrophysical behaviour of these three orthogonal splitting planes in granite is instrumental to understanding decay in ashlars and sculptures. The decay of building granite is different in each splitting plane. Alpedrete granite was the stone selected for this study based on the orientation and distribution of exfoliation microcracks and the characterisation of their implications for the anisotropy of petrophysical properties such as ultrasonic wave propagation, capillarity, air permeability, micro-roughness and surface hardness. Inter- and intracrystalline microcrack length and spacing were also measured and quantified. The findings show that the splitting planes in Alpedrete granite are determined by the orientation of exfoliation microcracks, which as a rule are generally straight and intracrystalline and determine the anisotropy of the petrophysical properties analysed. Splitting planes are the orientation that should be applied when performing laboratory tests for the petrographic and petrophysical properties of building granite. ; This study was funded by the Regional Government of Madrid, Spain, in the framework of the GEOMATERIALS-2CM [S2013/MIT-2914] programme. ; Peer reviewed

Silicon sub-wavelength structures have become a versatile design tool for practical, high-performance integrated optical devices, ranging from highly efficient grating couplers to ultra-broadband beam-splitters. Recently, some of the basic anisotropic properties of these structures have been proposed for advance device design. Here we explore these properties in detail, from the underlying physics to emerging applications in on-chip polarization management. ; Ministerio de Economía y Competitividad, Programa Estatal de Investigación, Desarrollo e Innovación Orientada a los Retos de la Sociedad (cofinanciado FEDER), Proyectos TEC2016-80718-R, TEC2015-71127-C2-1-R (FPI scholarship BES-2016-077798), and IJCI-2016-30484, the Community of Madrid (S2013/MIT-2790), the Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech, the EMPIR program (JRP-i22 14IND13 Photind), co-financed by the participating countries and the European Union's 2020 research and innovation program, and the Horizon 2020 research and innovation program under the Marie Sklodowska-Curie grant No. 734331.

In this work, we generalise linear magnetohydrodynamic (MHD) stability theory to include equilibrium pressure anisotropy in the fluid part of the analysis. A novel 'single-adiabatic' (SA) fluid closure is presented which is complementary to the usual 'double-adiabatic' (CGL) model and has the advantage of naturally reproducing exactly the MHD spectrum in the isotropic limit. As with MHD and CGL, the SA model neglects the anisotropic perturbed pressure and thus loses non-local fast-particle stabilisation present in the kinetic approach. Another interesting aspect of this new approach is that the stabilising terms appear naturally as separate viscous corrections leaving the isotropic SA closure unchanged. After verifying the self-consistency of the SA model, we re-derive the projected linear MHD set of equations required for stability analysis of tokamaks in the MISHKA code. The cylindrical wave equation is derived analytically as done previously in the spectral theory of MHD and clear predictions are made for the modification to fast-magnetosonic and slow ion sound speeds due to equilibrium anisotropy. ; This work was funded by the Australian Research Council through Grant Nos. DP1093797 and FT0991899. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 633053 and from the RCUK Energy Programme [grant number EP/I501045].

In this work, we generalise linear magnetohydrodynamic (MHD) stability theory to include equilibrium pressure anisotropy in the fluid part of the analysis. A novel 'single-adiabatic' (SA) fluid closure is presented which is complementary to the usual 'double-adiabatic' (CGL) model and has the advantage of naturally reproducing exactly the MHD spectrum in the isotropic limit. As with MHD and CGL, the SA model neglects the anisotropic perturbed pressure and thus loses non-local fast-particle stabilisation present in the kinetic approach. Another interesting aspect of this new approach is that the stabilising terms appear naturally as separate viscous corrections leaving the isotropic SA closure unchanged. After verifying the self-consistency of the SA model, we re-derive the projected linear MHD set of equations required for stability analysis of tokamaks in the MISHKA code. The cylindrical wave equation is derived analytically as done previously in the spectral theory of MHD and clear predictions are made for the modification to fast-magnetosonic and slow ion sound speeds due to equilibrium anisotropy. ; This work was funded by the Australian Research Council through Grant Nos. DP1093797 and FT0991899. This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement number 633053 and from the RCUK Energy Programme [grant number EP/I501045].

The effect of an applied electric field and the effect of charging are investigated on the magnetic anisotropy (MA) of various stable two-dimensional (2D) crystals such as graphene, FeCl2, graphone, fluorographene, and MoTe2 using first-principles calculations. We found that the magnetocrystalline anisotropy energy of Co-on-graphene and Os-doped-MoTe2 systems change linearly with electric field, opening the possibility of electric field tuning MA of these compounds. In addition, charging can rotate the easy-axis direction of Co-on-graphene and Os-doped-MoTe2 systems from the out-of-plane (in-plane) to in-plane (out-of-plane) direction. The tunable MA of the studied materials is crucial for nanoscale electronic technologies such as data storage and spintronics devices. Our results show that controlling the MA of the mentioned 2D crystal structures can be realized in various ways, and this can lead to the emergence of a wide range of potential applications where the tuning and switching of magnetic functionalities are important. ; Flemish Science Foundation (FWO-Vl); Methusalem Foundation of the Flemish government; Hercules Foundation; FWO Pegasus Marie Curie Fellowship; TUBITAK (111T318)