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Cordierite is widely found in metamorphic rocks, and has important application for geothermometry and geobarometry, as well as a monitor of volatile concentrations in fluids or melts. In this study, we measured high-temperature powder X-ray diffraction (XRD) patterns on a natural sample (Na 0.06 [(Mg 1.87 Fe 0.19)Al 3.94 Si 5.00 O 18.00 ](CO 2) 0.09 (H 2 O) 0.22) up to 1500 K. The thermal expansion coefficient is fitted with an average value of 7.39(19) × 10−6 K−1. In situ high-temperature and high-pressure Raman spectra were also obtained on this sample, on the basis of which the isobaric and isothermal Grüneisen parameters are calculated. The anharmonic correction has positive contribution to the heat capacity, since the intrinsic anharmonic parameters show systematically negative values. Next, the isothermal bulk modulus (K T) at high temperatures is modeled by density functional theory (DFT), which is essential for constructing the P-V-T equation of state (EOS) as well as thermodynamic Grüneisen parameter (γ V) for cordierite. The axial thermoelastic parameters and strain evolution along isochors at high temperatures are also evaluated. Cordierite is substantially softer with weaker anisotropy for axial compressibilities as compared with zircon and rutile, and consequently, significantly smaller strain effect is expected on the vibrational frequencies. Due to its smaller thermal expansivity and larger compressibility than garnets, the assemblage of cordierite trapped in garnet minerals can potentially be an elastic thermometer in the pressure range below 1 GPa. Entrapment isomekes are calculated with negative slopes of (∂ P /∂ T) V (inc-host) , and positive residual inclusion pressures are expected at the ambient condition. [Display omitted] • The thermal expansivity for natural cordierite is about 30% of those for garnets. • Anharmonic contributions to C V and γ V are evaluated as a function of temperature. • The cordierite-in-garnet assemblage can be a potential elastic geothermometer. [ABSTRACT FROM AUTHOR]

Structural refinements from single-crystal X-ray diffraction data are reported for olivine with a composition of Fo100 (forsterite Mg2SiO4, synthetic), Fo80 and Fo62 (~Mg1.6Fe0.4SiO4 and ~Mg1.24Fe0.76SiO4, both natural) at room temperature and high pressure to ~8 GPa. The new results, along with data from the literature on Fo0 (fayalite Fe2SiO4), were used to investigate the previously reported structural mechanisms which caused small variations of olivine bulk modulus with increasing Fe content. For all the investigated compositions, the M2 crystallographic site, with its bonding configuration and its larger polyhedral volume, was observed to control the compression mechanisms in olivine. From Fo100 to Fo0, the compression rates for M2–O and M1–O bond lengths were observed to control the relative polyhedral volumes, resulting in a less-compressible M1O6 polyhedral volume, likely causing the slight increase in bulk modulus with increasing Fe content. [ABSTRACT FROM AUTHOR]

Motion sickness (MS) is known to be a potentially limiting factor for future self-driving vehicles - specifically in regards to occupant comfort and well-being. With this as a consideration comes the desire to accurately measure, track and even predict MS state in real-time. Previous research has considered physiological measurements to measure MS state, although, this is mainly measured after an MS exposure and not throughout exposure(s) to a MS task. A unique contribution of this paper is in the real-time tracking of subjective MS alongside real-time physiological measurements of Electrodermal Activity (EDA) and skin temperature. Data was collected in both simulator-based (controlled) and on-road (naturalistic) studies. 40 participants provided at total of 61 data sets, providing 1603 min of motion sickness data for analysis. This study is in agreement that these measures are related to MS but evidenced a total lack of reliability for these measures at an individual level for both simulator and on-road experimentation. It is likely that other factors, such as environment and emotional state are more impactful on these physiological measures than MS itself. At a cohort level, the applicability of physiological measures is not considered useful for measuring MS accurately or reliably in real-time. Recommendations for further research include a mixed-measures approach to capture other data types (such as subject activity) and to remove contamination of physiological measures from environmental changes., (Copyright © 2020 Elsevier Ltd. All rights reserved.)

Everyone can be susceptible to motion sickness (except those with complete loss of labyrinth function) and around one in three are known to be servery susceptible. Motion sickness can be experienced in many domains, including car travel, on a boat, using virtual reality headsets and simulator use amongst others. It is expected that due to potential designs and use cases, self-driving cars will increase motion sickness onset likelihood and severity for many car travellers. Besides medication, there are limited methods through which one can actively reduce their motion sickness susceptibility. This research develops a novel visuospatial training tool and explores the effect of visuospatial training on motion sickness. With a combined sample of 42 participants split between driving simulator trials (n = 20), and on-road trials (n = 22) baseline visuospatial skills and motion sickness were first measured. After a 14-day training period where participates completed 15-min of pen and paper tasks per day, it was found that visuospatial skills improved by 40%. This increase in visuospatial ability was shown to be directly responsible for a reduction in motion sickness by 51% in the simulator (with a 60% reduction in participant dropouts) and a 58% reduction in the on-road trial. This research has successfully identified a new method to reduce motion sickness susceptibility and the impact of these findings have wide reaching implications for motion sickness research, especially in the field of self-driving vehicles., (Copyright © 2020. Published by Elsevier Ltd.)

The emerging picture of Earth's deep interior from seismic tomography indicates more complexity than previously thought. The presence of lateral anisotropy and heterogeneity in Earth's mantle highlights the need for fully anisotropic elasticity data from mineral physics. A breakthrough in high-frequency (gigahertz) ultrasound has resulted in transmission of pure-mode elastic shear waves into a high-pressure diamond-anvil cell using a P-to-S elastic-wave conversion. The full elastic tensor (c(ij)) of high-pressure minerals or metals can be measured at extreme conditions without optical constraints. Here we report the effects of pressure and composition on shear-wave velocities in the major lower-mantle oxide, magnesiowüstite-(Mg,Fe)O. Magnesiowüstite containing more than approximately 50% iron exhibits pressure-induced c(44) shear-mode softening, indicating an instability in the rocksalt structure. The oxide closer to expected lower-mantle compositions ( approximately 20% iron) shows increasing shear velocities more similar to MgO, indicating that it also should have a wide pressure-stability field. A complete sign reversal in the c(44) pressure derivative points to a change in the topology of the (Mg,Fe)O phase diagram at approximately 50-60% iron. The relative stability of Mg-rich (Mg,Fe)O and the strong compositional dependence of shear-wave velocities (and partial differential c(44)/ partial differential P) in (Mg,Fe)O implies that seismic heterogeneity in Earth's lower mantle may result from compositional variations rather than phase changes in (Mg,Fe)O.