438 research outputs found

    Women in geosciences within the Italian University system in the last 20 years

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    Abstract. This work aims at providing an updated scenario on the underrepresentation of women in the Italian university system in the area of geosciences in the last two decades. The retrieved official data on permanent full and associate professors in the 19-years considered highlight some positive trends: an increase in the number of female full professors from 9.0 % to 18.5 % and in female associate professors from 23.6 % to 28.9 %. However, although the number of female full professors almost doubled in this period, such increase still represents an excessively slow trend. Slightly better is the trend related to associate professors. The picture portrayed for non-permanent researchers, called RTD-b, as introduced by the Italian Law no. 240/2010 (essentially tenure-track associate professor position), instead raises strong concerns for the future seen that the female percentage is just 26 %, thus exhibiting a significant gender imbalance. This is even more significant if we consider that the student population in geosciences shows a gender imbalance of about 37 %, no gender gap at PhD level and a relatively high Glass Ceiling Index (GCI) during the career progression of women. An analysis of the geographical distribution of female researchers in geosciences has evidenced that, although the percentages of women are comparable, the GCI calculated in Southern Italy has been alarmingly high in the last 2–3 years and is divergent from the decrease observed in Northern and Central Italy. The work also analyses the gender balance over different areas of geosciences, showing that in Paleontology and Paleoecology the gap is inverted with more female than male professors, both at full and associate professor level, whereas the gap is almost closed in Mineralogy for associate professors, far though from being balanced for full professors. All remaining geological disciplines suffer a gender imbalance. Further analysis carried out in this work unveils that the number of female full professor is low (<10 %) both at national and regional level in the 2000–2009 decade, consistent with a GCI higher than 2.5–3. From 2010 to 2013, likely in response to the Italian Law no. 240 of 2010, an important progressive increase, associated with a decrease of GCI, is visible. However, from 2014 to 2019 the percentage remains constant (∼20 %) with the exception of Southern Italy, which displays a return to lower values (<15 %). Finally, an international comparison with countries like Germany and the USA definitively indicates that the Italian university system is more equal in terms of gender balance. Even if some significant and positive steps have been carried out in the Italian university system, still much effort is required to fight a general and crucial problem which is the gender balance issue. Results could be achieved promoting work-life balance policies that better reconcile family and work, stimulating a reorganization of the work system still currently set on the male model but, and more importantly, changing the prevailing patriarchal mentality. The Italian university system has already a great example to follow: the zero-pay gap. This is possibly the only system worldwide where male and female professors earn the same identical salary, compared to the salary gap of between 15 % and 30 % of countries richer than Italy, and must be the target to reach, in the near future, for gender balance

    Configurational and energy study of the (100) and (110) surfaces of the MgAl2O4 spinel by means of quantum-mechanical and empirical techniques

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    none3noneFrancesco Roberto Massaro;Marco Bruno;Fabrizio NestolaFrancesco Roberto, Massaro; Marco, Bruno; Nestola, Fabrizi

    Toward an accurate ab initio estimation of compressibility and thermal expansion of diamond in the [0, 3000 K] temperature and [0, 30 GPa] pressures ranges, at the hybrid HF/DFT theoretical level

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    The isothermal bulk modulus, together with its temperature dependence, and the thermal expansion of diamond at various pressures were calculated from first principles in the [0, 30 GPa] and [0, 3000 K] pressure and temperature ranges, within the limits of the quasi-harmonic approximation (QHA). The hybrid HF/DFT functional employed (WC1LYP) proved to be particularly effective in providing a very close agreement between the calculated and the available experimental data. In particular, the bulk modulus at 300 K was estimated to be 444.6 GPa (K' = 3.60); at the same temperature, the (volume) thermal expansion coefficient was 3.19×10-6 K-1. To the authors’ knowledge, among the theoretical papers devoted to the subject, the present one provides the most accurate thermo-elastic data in high-pressure and temperature ranges. Such data can confidently be used in the determination of the pressure of formation using the “elastic method” for minerals found as inclusions in diamonds (recently applied on different minerals included in diamonds), thus shedding light upon the genesis of diamonds in the Earth’s upper mantle

    A Study of Thermal Expansion on the Predicted Mercury Surface Minerals: Preparing for MERTIS on BepiColombo

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    The MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission unveiled that most of the detectable surface of Mercury is constituted by low-Fe and Mg-rich basalts [1,2], dismissing the previously assumed widespread presence of more felsic materials - as on the Moon’s surface. In this background, the BepiColombo mission will be fundamental to reveal the residual igneous crust of the Mercury surface, in order to assess its petrogenesis. The Mercury Radiometer and Thermal Infrared Spec¬trometer (MERTIS) on BepiColombo will be able to provide thermal infrared (TIR) emissivity spectra from 7 to 14 μm. This wavelength range is very useful to identify the structural properties of several silicates, and the position of the emissivity bands provides hints on the solid solutions. In addition to space-weathering degradation and impact-induced structural modifications, the thermal expansion driven by the daily tem¬perature variation of the surface of Mercury significantly affects the crystal structure and density of the present minerals and, consequently, their thermal infrared spectral signature. This behaviour has been recently demonstrated for several common terrestrial mineralogical phases [3,4,5], and could be even predicted for other silicates. A more difficult interpretation of the spectra arises, of course, from the simultaneous presence of different minerals, each one with its characteristic thermal expansion coefficient. In addition to the temperature-dependent spectral variations of single constituents (e.g. plagioclases, olivine, pyroxenes), the DLR Planetary Emissivity Laboratory (PEL) is measuring emissivity spectra of linear mixtures that most likely could be present on the surface of Mercury. To this aim, spectra of binary compositions (e.g., anorthosite, gabbro) and their single-phase components are measured along the MERTIS wavelength range in vacuum from low to high-temperatures - up to 450°C

    Forming and preserving aragonite in shear zones: First report of blueschist facies metamorphism in the Jabal Akhdar Dome, Oman Mountains

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    We report the first occurrence of high-pressure metamorphic aragonite in Precambrian carbonates of the Jabal Akhdar Dome in the Oman Mountains (northern Oman). We propose a model for both its formation at blueschist facies conditions and its subsequent preservation to the surface within the tectonic framework of the Late Cretaceous obduction of the Semail Ophiolite. Aragonite formed at temperature ∼350 °C and pressure ≥0.9 GPa and is preserved within mylonitic shear zones and in stretched-fiber dilational veins where the necessary conditions for its formation and preservation, such as plastic strain accommodation, fluid-enhanced mineralogical reactions, and an anisotropic permeability structure, were preferentially met with respect to the surrounding rock. High-strain structural domains are ideal sites to look for and study prograde and retrograde high-pressure metamorphic histories in deeply subducted and exhumed terrains

    The (100), (111) and (110) surfaces of diamond: an ab initio B3LYP study

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    We present an accurate ab initio study of the structure and surface energy of the low-index (100),(111) and (110) diamond faces, by using the hybrid Hartree-Fock/Density Functional B3LYPHamiltonian and a localized all-electron Gaussian-type basis set. A 2D periodic slab model has been adopted, for which convergence on both structural and energetic parameters has been thoroughly investigated. For all the three surfaces, possible relaxations and reconstructions have been considered; a detailed geometrical characterization is provided for the most stable structure of each orientation. Surface energy is discussed for all the investigated faces

    The High-Pressure Structural Evolution of Olivine along the Forsterite&#8211;Fayalite Join

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    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\u2013O and M1\u2013O 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

    In situ analysis of garnet inclusion in diamond using single-crystal X-ray diffraction and X-ray micro-tomography

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    none9A single crystal of garnet enclosed in a diamond from the Jericho kimberlite (Slave Craton, Canada) has been investigated using X-ray diffraction and X-ray micro-tomography. The novel experimental approach allowed us to determine the crystal structure of the garnet. The unit-cell edge a and fractional atomic coordinates of oxygen were used to determine the composition via an updated Margules model for garnets. The composition is Pyr(0.41(5))Alm(0.36(7))Gro(0.22(1))Uva(0.01(1)), which is indistinguishable from the eclogitic garnets found in other Jericho diamonds. We also demonstrated that residual pressures on the inclusion of up to 1 GPa do not affect significantly the determination of the garnet composition by structure refinement.noneFABRIZIO NESTOLA;M. MERLI;PAOLO NIMIS;M. PARISATTO;M. KOPYLOVA;A. DE;M. LONGO;L. ZIBERNA;M. MANGHNANINestola, Fabrizio; M., Merli; Nimis, Paolo; Parisatto, Matteo; M., Kopylova; A., De; Longo, Micaela; Ziberna, Luca; M., Manghnan
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